For info output, you can now specify the reduction values to print by setting

IOBasic::outInfo_reductions or add an option string to the variable name
in IOBasic::outInfo_vars. Scalar variables will be output by their value.

The option string syntax is

  IOBasic::outInfo_vars = "var1[reductions=<minimum maximum>] var2"

and might still change slightly in the future.


git-svn-id: http://svn.cactuscode.org/arrangements/CactusBase/IOBasic/trunk@96 b589c3ab-70e8-4b4d-a09f-cba2dd200880

10 files changed, 1256 insertions, 1073 deletions

diff --git a/src/GHExtension.c b/src/GHExtension.c
deleted file mode 100644
index df3d69c..0000000
--- a/src/GHExtension.c
+++ /dev/null
@@ -1,134 +0,0 @@
- /*@@
-   @file      GHExtension.c
-   @date      Friday 18th September
-   @author    Gabrielle Allen
-   @desc 
-   IO GH extension stuff.
-   @enddesc 
- @@*/
-
-/* #define DEBUG_IO */
-
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-
-#include "cctk.h"
-#include "cctk_Parameters.h"
-#include "iobasicGH.h"
-
-static const char *rcsid = "$Header$";
-
-CCTK_FILEVERSION(CactusBase_IOBasic_GHExtension_c)
-
-void *IOBasic_SetupGH (tFleshConfig *config, int convergence_level, cGH *GH)
-{
-  int i;
-  iobasicGH *newGH;
-
-  newGH = (iobasicGH *) malloc (sizeof (iobasicGH));
-  newGH->infovals = (CCTK_REAL **) 
-    malloc (CCTK_NumVars () * sizeof (CCTK_REAL *));
-  for (i=0;i<CCTK_NumVars ();i++) 
-  {
-    newGH->infovals[i] = (CCTK_REAL *) malloc (2  * sizeof (CCTK_REAL));
-  }
-
-  newGH->do_outScalar = (char *) malloc (CCTK_NumVars () * sizeof (char));
-  newGH->outScalar_last = (int *) malloc (CCTK_NumVars () * sizeof (int));
-
-  newGH->do_outInfo = (char *) malloc (CCTK_NumVars () * sizeof (char));
-  newGH->outInfo_last = (int *) malloc (CCTK_NumVars () * sizeof (int));
-
-  return newGH;
-}
-
-int IOBasic_InitGH (cGH *GH)
-{
-  int i;
-  iobasicGH *myGH; 
-  DECLARE_CCTK_PARAMETERS
-
-  /* get the handles for IOBasic extensions */
-  myGH = (iobasicGH *) GH->extensions [CCTK_GHExtensionHandle ("IOBasic")];
-  myGH->filenameListScalar = NULL;
-
-  /* How often to output */
-  myGH->outInfo_every  = out_every > 0 ? out_every : -1;
-  if (outInfo_every > 0)
-  {
-    myGH->outInfo_every = outInfo_every;
-  }
-
-  myGH->outScalar_every = out_every > 0 ? out_every : -1;
-  if (outScalar_every > 0)
-  {
-    myGH->outScalar_every = outScalar_every;
-  }
-
-  /* Check whether "outdirScalar" was set.
-     If so take this dir otherwise default to "IO::outdir" */
-  if (CCTK_ParameterQueryTimesSet ("outdirScalar", CCTK_THORNSTRING) > 0)
-  {
-    myGH->outdirScalar = strdup (outdirScalar);
-  }  
-  else
-  {
-    myGH->outdirScalar = strdup (outdir);
-  }
-
-  /* create the output dir */
-  if (CCTK_MyProc (GH) == 0)
-  {
-    i = CCTK_CreateDirectory (0755,myGH->outdirScalar);
-    if (i < 0)
-    {
-      CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
-		  "IOBasic_InitGH: Problem creating Scalar output directory '%s'", 
-		  myGH->outdirScalar);
-    }
-    if (i > 0)
-    {
-      CCTK_VWarn (2, __LINE__, __FILE__, CCTK_THORNSTRING,
-		  "IOBasic_InitGH: Scalar output directory '%s' already exists", 
-		  myGH->outdirScalar);
-    }
-  }
-
-  for (i=0; i<CCTK_NumVars(); i++)
-  {
-    myGH->outScalar_last[i] = -1;
-    myGH->outInfo_last [i]  = -1;
-    myGH->infovals[i][0]    = 0.0;
-    myGH->infovals[i][1]    = 0.0;
-  }
-
-  myGH->filenameListScalar = NULL;
-
-  /* Provide Information */
-  if (CCTK_Equals(newverbose,"standard") || CCTK_Equals(newverbose,"full"))
-  {
-    if (myGH->outInfo_every > 0)
-    {
-      CCTK_VInfo("IOBasic","Info: Output every %d iterations",
-		 myGH->outInfo_every);
-    }
-    else
-    {
-      CCTK_VInfo("IOBasic","Info: No output requested");
-    }
-    CCTK_INFO("Info: Output to screen (standard output)");
-    if (myGH->outScalar_every > 0)
-    {
-      CCTK_VInfo("IOBasic","Scalar: Output every %d iterations",
-		 myGH->outScalar_every);
-    }
-    else
-    {
-      CCTK_VInfo("IOBasic","Scalar: No output requested");
-    }
-    CCTK_VInfo("IOBasic","Scalar: Output to directory %s",myGH->outdirScalar);
-  }
-
-  return 0;
-}
diff --git a/src/OutputInfo.c b/src/OutputInfo.c
index 2d763e6..0527425 100644
--- a/src/OutputInfo.c
+++ b/src/OutputInfo.c
@@ -2,14 +2,14 @@
    @file      OutputInfo.c
    @date      June 31 1999
    @author    Gabrielle Allen
-   @desc 
+   @desc
               Functions to deal with info output of variables
-   @enddesc 
-   @version   $Header$
+   @enddesc
+   @version   $Id$
  @@*/
- 
+
 #include <math.h>
-#include <stdio.h>
+#include <ctype.h>
 #include <stdlib.h>
 #include <string.h>
 
@@ -21,349 +21,202 @@
 static const char *rcsid = "$Header$";
 CCTK_FILEVERSION(CactusBase_IOBasic_OutputInfo_c)
 
+/********************************************************************
+ ********************    Macro Definitions    ***********************
+ ********************************************************************/
 /* uncomment the following to get some debugging output */
-/* #define IO_DEBUG 1 */
+/* #define IOBASIC_DEBUG 1 */
 
-/* the number at which to switch from decimal to exp notation */
+/* the number at which to switch from decimal to exponential notation */
 #define DECIMAL_PRECISION       1.0e-8
 #define DECIMAL_TOOBIG          1.0e+8
 #define USE_DECIMAL_NOTATION(x) ((fabs (x) > DECIMAL_PRECISION) ||            \
                                  ((x) == 0.0) ||                              \
                                  (fabs(x) < DECIMAL_TOOBIG))
-
-/* prototypes of routines defined in this source file */
-int IOBasic_OutputInfoGH (cGH *GH);
-int IOBasic_TimeForInfo (cGH *GH, int vindex);
-int IOBasic_TriggerOutputInfo (cGH *GH, int vindex);
-static void SetOutputFlag (int vindex, const char *optstring, void *arg);
-
-/* static variables */
-static int print_header = 1;
-static int outInfo_vars_lastset = -1;
+#define PRINT_FORMATTED_REDUCTION_VALUE(reduction)                            \
+          if (reduction->is_valid)                                            \
+          {                                                                   \
+            if (USE_DECIMAL_NOTATION (reduction->value))                      \
+            {                                                                 \
+              printf ("%13.8f |", reduction->value);                          \
+            }                                                                 \
+            else                                                              \
+            {                                                                 \
+              printf ("%11.6e |", reduction->value);                          \
+            }                                                                 \
+          }                                                                   \
+          else                                                                \
+          {                                                                   \
+            printf (" ----------- |");                                        \
+          }
+
+
+/********************************************************************
+ ********************    Internal Routines   ************************
+ ********************************************************************/
+static void CheckSteerableParameters (iobasicGH *myGH);
+static void AssignReductionList (int vindex, const char *optstring, void *arg);
+static void PrintHeader (iobasicGH *myGH, int num_vars);
 
 
  /*@@
-   @routine    IOBasic_OutputInfoGH
+   @routine    IOBasic_InfoOutputGH
    @date       June 31 1999
    @author     Gabrielle Allen
    @desc
                Loops over all variables and prints output if requested
    @enddesc
-   @calls      CCTK_GHExtension
-               CCTK_ParameterQueryTimesSet
-               CCTK_TraverseString
-               CCTK_NumVars
-               CCTK_VarName
+   @calls      CheckSteerableParameters
+               PrintHeader
                IOBasic_WriteInfo
 
    @var        GH
    @vdesc      Pointer to CCTK GH
    @vtype      cGH *
    @vio        in
-   @endvar 
+   @endvar
 
    @returntype int
    @returndesc
                0 for success
    @endreturndesc
 @@*/
-int IOBasic_OutputInfoGH (cGH *GH)
+int IOBasic_InfoOutputGH (cGH *GH)
 {
   DECLARE_CCTK_PARAMETERS
-  int i;
-  int ierr1;
-  int ierr2;
-  int times_set;
-  int out_old;
-  const char *vname;
+  int vindex, num_vars;
+  iobasic_reduction_t *reduction;
   iobasicGH  *myGH;
-  char ll[80], l1[1024], l2[1024], l3[1024];
 
 
-  /* Get the GH extensions for IOBasic */
+  /* get the GH extensions for IOBasic */
   myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
 
-  /* How often to output */
-  out_old = myGH->outInfo_every;
-  myGH->outInfo_every  = out_every > 0 ? out_every : -1;
-  if (outInfo_every > 0)
-  {
-    myGH->outInfo_every = outInfo_every;
-  }
-  if (myGH->outInfo_every != out_old)
-  {
-    if (CCTK_Equals(newverbose,"standard") || CCTK_Equals(newverbose,"full"))
-    {
-      CCTK_VInfo("IOBasic","Info: Output every %d iterations",
-		 myGH->outInfo_every);
-    }
-  }
-    
-  /* Return if no output is required */
-  if (myGH->outInfo_every < 1 || 
-      GH->cctk_iteration % myGH->outInfo_every != 0)
+  /* check if steerable parameters changed */
+  CheckSteerableParameters (myGH);
+
+  /* return if no output is required */
+  if (myGH->outInfo_every <= 0 || GH->cctk_iteration % myGH->outInfo_every)
   {
     return (0);
   }
 
-  /* re-parse the 'outInfo_vars' parameter if it was changed
-     and also print a header */
-  times_set = CCTK_ParameterQueryTimesSet ("outInfo_vars", CCTK_THORNSTRING);
-  if (times_set != outInfo_vars_lastset) 
+  /* print header if neccessary */
+  num_vars = CCTK_NumVars ();
+  if (myGH->info_reductions_changed)
   {  
-    memset (myGH->do_outInfo, 0, CCTK_NumVars ());
-    CCTK_TraverseString (outInfo_vars, SetOutputFlag, myGH->do_outInfo,
-                         CCTK_GROUP_OR_VAR);
-
-    if (CCTK_Equals(newverbose,"full"))
-    {
-      for (i=0;i<CCTK_NumVars();i++)
-      {
-	if (myGH->do_outInfo[i] > 0)
-	{
-	  CCTK_VInfo("IOBasic","Info: Output requested for %s",
-		     CCTK_VarName(i));
-	}
-      }
-    }
-
-    /* Save the last setting of 'outInfo_vars' parameter */
-    outInfo_vars_lastset = times_set;
-
-    print_header = 1;
-  }
-
-  if (print_header)
-  {
-    print_header = 0;
-
-    sprintf (l1," it  |         |");
-    sprintf (l2,"     |    t    |");
-    sprintf (l3,"----------------");
-      
-    for (i = 0; i < CCTK_NumVars (); i++)
-    {
-      if (myGH->do_outInfo[i])
-      {
-        if(CCTK_GroupTypeFromVarI(i) != CCTK_SCALAR)
-        {
-          sprintf (ll, "                                        ");
-          ll[25 - strlen (CCTK_VarName (i))] = '\0';
-          sprintf (l1, "%s %s%s |", l1, CCTK_VarName (i), ll);
-          sprintf (l2, "%s Min          Max          |", l2);
-          sprintf (l3, "%s----------------------------", l3);
-        }
-        else
-        {
-          sprintf (ll, "                                        ");
-          ll[25 - strlen (CCTK_VarName (i))] = '\0';
-          sprintf (l1, "%s %s%s |", l1, CCTK_VarName (i), ll);
-          sprintf (l2, "%s Value                     |", l2);
-          sprintf (l3, "%s----------------------------", l3);
-        }
-      }
-    }
-    printf ("%s\n%s\n%s\n%s\n", l3, l1, l2, l3);
-    fflush (stdout);
+    PrintHeader (myGH, num_vars);
   }
 
-
-  /* Print the iteration/timestep information for all variables */        
+  /* print the iteration/timestep information for all variables */
   if (USE_DECIMAL_NOTATION (GH->cctk_time))
   {
-    printf ("%4d |%9.3f|", GH->cctk_iteration, GH->cctk_time);    
-  }  
+    printf ("%5d |%9.3f |", GH->cctk_iteration, GH->cctk_time);
+  }
   else
   {
-    printf ("%4d |%7.3e|", GH->cctk_iteration, GH->cctk_time);
+    printf ("%5d |%7.3e |", GH->cctk_iteration, GH->cctk_time);
   }
 
-  /* Loop over all variables */
-  for (i = 0; i < CCTK_NumVars (); i++) 
+  /* loop over all variables */
+  for (vindex = 0; vindex < num_vars; vindex++)
   {
-
-    /* Check this Variable should be output */
-    if (! myGH->do_outInfo[i])
+    /* check this variable should be output */
+    if (myGH->info_reductions[vindex].num_reductions == 0)
     {
       continue;
     }
 
-    ierr1 = ierr2 = 0;
-
-    /* Check variable not already output this iteration */
-    if (myGH->outInfo_last[i] != GH->cctk_iteration) 
+    /* check variable not already output this iteration */
+    if (myGH->outInfo_last[vindex] != GH->cctk_iteration)
     {
-
-      /* Get the variable name for this index (for filename) */
-      vname = CCTK_VarName (i);
-
-#ifdef IO_DEBUG
+#ifdef IOBASIC_DEBUG
       printf("\nIn IO OutputInfoGH\n----------------\n");
-      printf("  Index = %d\n", i);
-      printf("  Variable = -%s-\n", vname);
-      printf("  Last output iteration was = %d\n", myGH->outInfo_last[i]);
+      printf("  Index = %d\n", vindex);
+      printf("  Variable = -%s-\n", CCTK_VarName (vindex);
+      printf("  Last output iteration was = %d\n", myGH->outInfo_last[vindex]);
 #endif
 
-      if(CCTK_GroupTypeFromVarI(i) != CCTK_SCALAR)
-      {
-        /* Make the IO call */
-        ierr1 = IOBasic_WriteInfo (GH, &myGH->infovals[i][0], i, "minimum",vname);
-        ierr2 = IOBasic_WriteInfo (GH, &myGH->infovals[i][1], i, "maximum",vname);
-      }
-      else
-      {
-        myGH->infovals[i][0] = *(CCTK_REAL *)GH->data[i][0];
-        myGH->infovals[i][1] = *(CCTK_REAL *)GH->data[i][0];
-      }
-      /* Register GF as having info output this iteration */
-      myGH->outInfo_last[i] = GH->cctk_iteration;
+      /* get the data to output */
+      IOBasic_WriteInfo (GH, vindex);
+
+      /* register variable as having info output this iteration */
+      myGH->outInfo_last[vindex] = GH->cctk_iteration;
     }
 
-    if(CCTK_GroupTypeFromVarI(i) != CCTK_SCALAR)
+    /* finally print the stuff to screen */
+    reduction = myGH->info_reductions[vindex].reductions;
+    while (reduction)
     {
-      if (ierr1 == 0)
-      {
-        /* finally print out the stuff */
-        if (USE_DECIMAL_NOTATION (myGH->infovals[i][0]))
-        {
-          printf ("%12.8f |", myGH->infovals[i][0]);
-        }
-        else
-        {
-          printf ("%10.6e |", myGH->infovals[i][0]);
-        }
-      }
-      else
-      {
-        printf(" ----------- |");
-      }
-      
-      if (ierr2 == 0)
-      {
-        if (USE_DECIMAL_NOTATION (myGH->infovals[i][1]))
-        {
-          printf ("%12.8f |", myGH->infovals[i][1]);
-        }
-        else
-        {
-        printf ("%10.6e |", myGH->infovals[i][1]);
-        }
-      }
-      else
-      {
-        printf(" ----------- |");
-      }
+      PRINT_FORMATTED_REDUCTION_VALUE (reduction);
+      reduction = reduction->next;
     }
-    else
-    {
-      if (USE_DECIMAL_NOTATION (myGH->infovals[i][0]))
-      {
-        printf (" %12.8f              |", myGH->infovals[i][0]);
-      }
-      else
-      {
-        printf (" %10.6e              |", myGH->infovals[i][0]);
-      }
-    }      
   } /* end of loop over all variables */
 
-  /* Add the new line */
-  printf ("\n");
-  fflush(stdout);
+  /* add the new line */
+  putchar ('\n');
+  fflush (stdout);
 
   return (0);
 }
 
 
  /*@@
-   @routine    IOBasic_TimeForInfo
+   @routine    IOBasic_TimeForInfoOutput
    @date       June 31 1999
    @author     Gabrielle Allen
    @desc
                Decides if it is time to output a variable using info output
    @enddesc
-   @calls      CCTK_GHExtensionHandle 
-               CCTK_GroupTypeFromVarI
-               CCTK_WARN
-               CCTK_QueryGroupStorageI 
-               CCTK_GroupFromVar               
- 
+   @calls      CheckSteerableParameters
+
    @var        GH
    @vdesc      Pointer to CCTK GH
    @vtype      cGH *
    @vio        in
-   @endvar 
+   @endvar
    @var        vindex
-   @vdesc      index of variable to output
+   @vdesc      index of variable to check for output
    @vtype      int
    @vio        in
-   @endvar 
+   @endvar
 
    @returntype int
    @returndesc
                true/false (1 or 0) if this variable should be output or not
    @endreturndesc
 @@*/
-int IOBasic_TimeForInfo (cGH *GH, int vindex)
+int IOBasic_TimeForInfoOutput (cGH *GH, int vindex)
 {
   DECLARE_CCTK_PARAMETERS
   int retval;
-  int times_set;
+  char *vname;
   iobasicGH *myGH;
-  char *fullname;
 
 
-  /* Default is do not do output */
-  retval = 0;
-
-  /* Get the GH extensions for IOBasic */
+  /* get the GH extensions for IOBasic */
   myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
 
-  /* How often to output */
-  myGH->outInfo_every  = out_every > 0 ? out_every : -1;
-  if (outInfo_every > 0)
-  {
-    myGH->outInfo_every = outInfo_every;
-  }
+  /* check if steerable parameters changed */
+  CheckSteerableParameters (myGH);
 
   /* return if no output requested */
-  if (myGH->outInfo_every <= 0)
-  {
-    return (0);
-  }
-
-  /* re-parse the 'outInfo_vars' parameter if it was changed
-     and also print a header */
-  times_set = CCTK_ParameterQueryTimesSet ("outInfo_vars", CCTK_THORNSTRING);
-  if (times_set != outInfo_vars_lastset) 
+  if (myGH->outInfo_every <= 0 || GH->cctk_iteration % myGH->outInfo_every ||
+      myGH->info_reductions[vindex].num_reductions == 0)
   {
-    memset (myGH->do_outInfo, 0, CCTK_NumVars ());
-    CCTK_TraverseString (outInfo_vars, SetOutputFlag, myGH->do_outInfo,
-                         CCTK_GROUP_OR_VAR);
-
-    /* Save the last setting of 'outInfo_vars' parameter */
-    outInfo_vars_lastset = times_set;
-
-    print_header = 1;
+    retval = 0;
   }
-
-  /* Check if this variable should be output */
-  if (myGH->do_outInfo[vindex] &&
-      (GH->cctk_iteration % myGH->outInfo_every == 0))
+  else
   {
-      
-    /* Check GF not already output this iteration */
-    if (myGH->outInfo_last[vindex] == GH->cctk_iteration)
+    /* check if not already output this iteration */
+    retval = myGH->outInfo_last[vindex] != GH->cctk_iteration;
+    if (! retval)
     {
-      fullname = CCTK_FullName (vindex);
+      vname = CCTK_FullName (vindex);
       CCTK_VWarn (5, __LINE__, __FILE__, CCTK_THORNSTRING,
                   "Already done Info output for '%s' in current "
-                  "iteration (probably via triggers)", fullname);
-      free (fullname);
-    }
-    else
-    {
-      retval = 1;
+                  "iteration (probably via triggers)", vname);
+      free (vname);
     }
   }
 
@@ -372,14 +225,13 @@ int IOBasic_TimeForInfo (cGH *GH, int vindex)
 
 
  /*@@
-   @routine    IOBasic_TriggerOutputInfo
+   @routine    IOBasic_TriggerInfoOutput
    @date       June 31 1999
    @author     Gabrielle Allen
    @desc
                Triggers the output of a variable using IOBasic's info output
    @enddesc
-   @calls      CCTK_GHExtensionHandle 
-               IOBasic_WriteInfo
+   @calls      IOBasic_WriteInfo
 
    @var        GH
    @vdesc      Pointer to CCTK GH
@@ -397,49 +249,397 @@ int IOBasic_TimeForInfo (cGH *GH, int vindex)
                0 for success
    @endreturndesc
 @@*/
-int IOBasic_TriggerOutputInfo (cGH *GH, int vindex)
+int IOBasic_TriggerInfoOutput (cGH *GH, int vindex)
 {
+  DECLARE_CCTK_PARAMETERS
   iobasicGH *myGH;
-  const char *vname;
 
 
-  /* Get the GH extension for IOBasic */
+  /* get the GH extension for IOBasic */
   myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
- 
-  vname = CCTK_VarName (vindex);
 
-  /* Do the Info output */
-#ifdef IO_DEBUG
+#ifdef IOBASIC_DEBUG
   printf ("\nIn IO TriggerOutputInfo\n---------------------\n");
   printf ("  Index = %d\n", vindex);
-  printf ("  Variable = -%s-\n", vname);
+  printf ("  Variable = -%s-\n", CCTK_VarName (vindex);
 #endif
-  
-  IOBasic_WriteInfo (GH, &myGH->infovals[vindex][0], vindex, "minimum", vname);
-  IOBasic_WriteInfo (GH, &myGH->infovals[vindex][1], vindex, "maximum", vname);
 
-  /* Register variable as having Info output at this iteration */
+  /* get the data values to output */
+  IOBasic_WriteInfo (GH, vindex);
+
+  /* gegister variable as having Info output at this iteration */
   myGH->outInfo_last[vindex] = GH->cctk_iteration;
 
   return (0);
 }
 
 
-/***************************************************************************/
-/*                            local functions                              */
-/***************************************************************************/
-/* callback for CCTK_TraverseString() to set the output flag
-   for the given variable */
-static void SetOutputFlag (int vindex, const char *optstring, void *arg)
+/********************************************************************
+ ********************    Internal Routines   ************************
+ ********************************************************************/
+ /*@@
+   @routine    CheckSteerableParameters
+   @date       Tue 31 Jul 2001
+   @author     Thomas Radke
+   @desc
+               Re-evaluates 'IOBasic::outInfo_every' and/or 'IO::out_every'
+               resp. to set myGH->outInfo_every to the frequency of info output.
+               Re-evaluates 'IOBasic::outInfo_vars' and
+               'IOBasic::outInfo_reductions' and sets
+               myGH->info_reductions_changed to true if one of them was changed.
+   @enddesc
+   @calls      CCTK_ParameterQueryTimesSet
+
+   @var        myGH
+   @vdesc      Pointer to IOBasic's GH extension
+   @vtype      iobasicGH *
+   @vio        in
+   @endvar
+@@*/
+static void CheckSteerableParameters (iobasicGH *myGH)
+{
+  DECLARE_CCTK_PARAMETERS
+  int out_old, times_set;
+  static int outInfo_vars_lastset       = -1;
+  static int outInfo_reductions_lastset = -1;
+
+
+  /* how often to output */
+  out_old = myGH->outInfo_every;
+  myGH->outInfo_every  = out_every > 0 ? out_every : -1;
+  if (outInfo_every > 0)
+  {
+    myGH->outInfo_every = outInfo_every;
+  }
+  if (myGH->outInfo_every != out_old)
+  {
+    if (CCTK_Equals (newverbose, "standard") ||
+        CCTK_Equals (newverbose, "full"))
+    {
+      CCTK_VInfo (CCTK_THORNSTRING, "Info: Output every %d iterations",
+                  myGH->outInfo_every);
+    }
+  }
+
+  /* return if there's nothing to do */
+  if (myGH->outInfo_every <= 0)
+  {
+    return;
+  }
+
+  /* check if the 'outInfo_reductions' parameter if it was changed */
+  times_set = CCTK_ParameterQueryTimesSet ("outInfo_reductions",
+                                           CCTK_THORNSTRING);
+  myGH->info_reductions_changed |= times_set != outInfo_reductions_lastset;
+  outInfo_reductions_lastset = times_set;
+
+  /* check if the 'outInfo_vars' parameter if it was changed */
+  times_set = CCTK_ParameterQueryTimesSet ("outInfo_vars", CCTK_THORNSTRING);
+  myGH->info_reductions_changed |= times_set != outInfo_vars_lastset;
+  outInfo_vars_lastset = times_set;
+}
+
+
+ /*@@
+   @routine    AssignReductionList
+   @date       Tue 31 Jul 2001
+   @author     Thomas Radke
+   @desc
+               Callback routine called by CCTK_TraverseString() to set the
+               info output for a given variable.
+               For CCTK_GF and CCTK_ARRAY variables, it builds a chained list
+               of reduction operators according to the settings of 'optstring'
+               or 'IOBasic::outInfo_reductions'.
+   @enddesc
+   @calls      CCTK_GroupTypeFromVarI
+               CCTK_ReductionHandle
+
+   @var        vindex
+   @vdesc      index of the variable to set info output
+   @vtype      int
+   @vio        in
+   @endvar
+   @var        optstring
+   @vdesc      option string for this variable
+   @vtype      const char *
+   @vio        in
+   @endvar
+   @var        arg
+   @vdesc      user-supplied argument to callback routine (IOBasic GH extension)
+   @vtype      void *
+   @vio        in
+   @endvar
+@@*/
+static void AssignReductionList (int vindex, const char *optstring, void *arg)
 {
-  char *flags = (char *) arg;
+  DECLARE_CCTK_PARAMETERS
+  iobasicGH *myGH = (iobasicGH *) arg;
+  const char *string_start, *string_end;
+  char *reduction_op, *reduction_op_list;
+  int reduction_handle;
+  iobasic_reductionlist_t *list;
+  iobasic_reduction_t **new_reduction;
+
+
+  list = &myGH->info_reductions[vindex];
+
+  if (CCTK_GroupTypeFromVarI (vindex) == CCTK_SCALAR)
+  {
+    if (optstring)
+    {
+      CCTK_VWarn (5, __LINE__, __FILE__, CCTK_THORNSTRING,
+                  "option list '%s' for variable '%s' ignored",
+                  optstring, CCTK_VarName (vindex));
+    }
+
+    list->reductions = (iobasic_reduction_t *)
+                       malloc (sizeof (iobasic_reduction_t));
+    if (strncmp (CCTK_VarTypeName (CCTK_VarTypeI (vindex)),
+                 "CCTK_VARIABLE_COMPLEX", 21))
+    {
+      list->num_reductions = 1;
+      list->reductions->name = strdup ("scalar value");
+      list->reductions->next = NULL;
+    }
+    else
+    {
+      list->num_reductions = 2;
+      list->reductions->name = strdup ("real part");
+      list->reductions->next = (iobasic_reduction_t *)
+                               malloc (sizeof (iobasic_reduction_t));
+      list->reductions->next->name = strdup ("imag part");
+      list->reductions->next->next = NULL;
+    }
+
+#ifdef IOBASIC_DEBUG
+    printf ("Set info scalar output for variable '%s'\n", CCTK_VarName(vindex));
+#endif
 
+    return;
+  }
 
-  flags[vindex] = 1;
+  /* initialize to empty list */
+  list->num_reductions = 0;
+  list->reductions = NULL;
 
   if (optstring)
   {
-    CCTK_VWarn (5, __LINE__, __FILE__, CCTK_THORNSTRING,
-                "Optional string '%s' in variable name ignored", optstring);
+    if (strncmp (optstring, "reductions=<", 12) == 0 &&
+        optstring[strlen (optstring) - 1] == '>')
+    {
+      reduction_op_list = strdup (optstring + 12);
+      reduction_op_list[strlen (reduction_op_list) - 1] = 0;
+    }
+    else
+    {
+      CCTK_VWarn (5, __LINE__, __FILE__, CCTK_THORNSTRING,
+                  "AssignReductionList: invalid syntax for option list '%s'",
+                  optstring);
+      return;
+    }
+  }
+  else
+  {
+    reduction_op_list = strdup (outInfo_reductions);
+  }
+
+  /* now loop over all reduction operators */
+  string_start = reduction_op_list;
+  reduction_op = (char *) malloc (strlen (string_start) + 1);
+  while (string_start && *string_start)
+  {
+    /* skip leading spaces */
+    while (isspace ((int) *string_start))
+    {
+      string_start++;
+    }
+    if (! *string_start)
+    {
+      break;
+    }
+
+    /* advance to end of the operator string */
+    string_end = string_start + 1;
+    while (*string_end && ! isspace ((int) *string_end))
+    {
+      string_end++;
+    }
+
+    /* copy the operator string */
+    strncpy (reduction_op, string_start, string_end - string_start);
+    reduction_op[string_end - string_start] = 0;
+    string_start = string_end;
+
+    /* get the reduction handle from the reduction operator */
+    reduction_handle = CCTK_ReductionHandle (reduction_op);
+    if (reduction_handle < 0)
+    {
+      CCTK_VWarn (5, __LINE__, __FILE__, CCTK_THORNSTRING,
+                  "AssignReductionList: Invalid reduction operator '%s'",
+                  reduction_op);
+      continue;
+    }
+
+    /* add new reduction to end of list */
+    new_reduction = &list->reductions;
+    while (*new_reduction)
+    {
+      if (strcmp ((*new_reduction)->name, reduction_op) == 0)
+      {
+        new_reduction = NULL;
+        break;
+      }
+      new_reduction = &((*new_reduction)->next);
+    }
+    if (new_reduction == NULL)
+    {
+      CCTK_VWarn (3, __LINE__, __FILE__, CCTK_THORNSTRING,
+                  "AssignReductionList: Duplicate reduction operator '%s' will "
+                  "be ignored", reduction_op);
+      continue;
+    }
+
+    *new_reduction = (iobasic_reduction_t *) malloc (sizeof (iobasic_reduction_t));
+    (*new_reduction)->handle = reduction_handle;
+    (*new_reduction)->name   = strdup (reduction_op);
+    (*new_reduction)->next   = NULL;
+    list->num_reductions++;
+
+#ifdef IOBASIC_DEBUG
+    printf ("Set info reduction output '%s' for variable '%s'\n",
+            (*new_reduction)->name, CCTK_VarName (vindex));
+#endif
+  }
+
+  free (reduction_op_list);
+  free (reduction_op);
+}
+
+
+ /*@@
+   @routine    PrintHeader
+   @date       Tue 31 Jul 2001
+   @author     Thomas Radke
+   @desc
+               It re-evaluates the info reduction lists of all CCTK variables
+               and prints the header for the info output table.
+   @enddesc
+   @calls      CCTK_TraverseString
+
+   @var        myGH
+   @vdesc      Pointer to IOBasic's GH extension
+   @vtype      iobasicGH *
+   @vio        in
+   @endvar
+   @var        num_vars
+   @vdesc      total number of CCTK variables
+   @vtype      int
+   @vio        in
+   @endvar
+@@*/
+static void PrintHeader (iobasicGH *myGH, int num_vars)
+{
+  DECLARE_CCTK_PARAMETERS
+  int i, num_columns, vindex;
+  char *vname;
+  iobasic_reduction_t *reduction, *next;
+
+
+  /* free old info output lists ... */
+  for (vindex = 0; vindex < num_vars; vindex++)
+  {
+    if (myGH->info_reductions[vindex].num_reductions > 0)
+    {
+      myGH->info_reductions[vindex].num_reductions = 0;
+      reduction = myGH->info_reductions[vindex].reductions;
+      while (reduction)
+      {
+        next = reduction->next;
+        free (reduction->name);
+        free (reduction);
+        reduction = next;
+      }
+    }
+  }
+  /* ... and create new ones */
+  if (CCTK_TraverseString (outInfo_vars, AssignReductionList, myGH,
+                           CCTK_GROUP_OR_VAR) < 0)
+  {
+    CCTK_WARN (1, "Failed to parse 'IOBasic::outInfo_vars' parameter");
   }
+
+  /* count number of info values to output */
+  num_columns = 0;
+  for (vindex = 0; vindex < num_vars; vindex++)
+  {
+    num_columns += myGH->info_reductions[vindex].num_reductions;
+
+    if (myGH->info_reductions[vindex].num_reductions > 0 &&
+        CCTK_Equals (newverbose, "full"))
+    {
+      CCTK_VInfo (CCTK_THORNSTRING, "Info: Output requested for variable '%s'",
+                  CCTK_VarName (vindex));
+    }
+  }
+
+  /* draw a horizontal delimiter line */
+  printf ("------------------");
+  for (i = 0; i < num_columns; i++)
+  {
+    printf ("---------------");
+  }
+  putchar ('\n');
+
+  /* the first header line displays the iteration number (first column)
+     and the full names of the variables to output (third column ff.) */
+  printf ("  it  |          |");
+  if (num_columns > 0)
+  {
+    for (vindex = 0; vindex < num_vars; vindex++)
+    {
+      i = myGH->info_reductions[vindex].num_reductions;
+      if (i > 0)
+      {
+        vname = CCTK_FullName (vindex);
+        if (strlen (vname) > (unsigned int) 15*i - 3)
+        {
+          printf (" *%s |", vname + strlen (vname) - (15*i - 4));
+        }
+        else
+        {
+          printf (" %-*s |", 15*i - 3, vname);
+        }
+        free (vname);
+      }
+    }
+  }
+  putchar ('\n');
+
+  /* the second header line displays the physical time (second column)
+     and the names of the reduction operators to apply (third column ff.) */
+  printf ("      |    t     ");
+  for (vindex = 0; vindex < num_vars; vindex++)
+  {
+    if (myGH->info_reductions[vindex].num_reductions > 0)
+    {
+      reduction = myGH->info_reductions[vindex].reductions;
+      while (reduction)
+      {
+        printf ("| %-12s ", reduction->name);
+        reduction = reduction->next;
+      }
+    }
+  }
+  printf ("|\n");
+
+  /* finally draw another horizontal delimiter line */
+  printf ("------------------");
+  for (i = 0; i < num_columns; i++)
+  {
+    printf ("---------------");
+  }
+  putchar ('\n');
+  fflush (stdout);
+
+  myGH->info_reductions_changed = 0;
 }
diff --git a/src/Output.c b/src/OutputScalar.c
index 0461611..155b1dc 100644
--- a/src/Output.c
+++ b/src/OutputScalar.c
@@ -3,11 +3,11 @@
    @date      Mon 21 September
    @author    Gabrielle Allen
    @desc 
-   Functions to deal with scalar output of grid variables
+              Functions to deal with scalar output of grid variables
    @enddesc 
  @@*/
  
-/*#define IO_DEBUG*/
+/* #define IOBASIC_DEBUG 1 */
 
 #include <stdio.h>
 #include <stdlib.h>
@@ -22,14 +22,12 @@ static const char *rcsid = "$Header$";
 CCTK_FILEVERSION(CactusBase_IOBasic_Output_c)
 
 /* function prototypes */
-int IOBasic_TimeForOutput (cGH *GH, int vindex);
-int IOBasic_OutputGH (cGH *GH);
 static void CheckSteerableParameters (iobasicGH *myGH);
 static void SetOutputFlag (int vindex, const char *optstring, void *arg);
 
 
 /*@@
-   @routine    IOBasic_OutputGH
+   @routine    IOBasic_ScalarOutputGH
    @date       Sat March 6 1999
    @author     Gabrielle Allen
    @desc
@@ -45,7 +43,7 @@ static void SetOutputFlag (int vindex, const char *optstring, void *arg);
    @vio     in
    @endvar
 @@*/
-int IOBasic_OutputGH (cGH *GH)
+int IOBasic_ScalarOutputGH (cGH *GH)
 {
   int vindex;
   const char *name;
@@ -53,7 +51,7 @@ int IOBasic_OutputGH (cGH *GH)
 
 
   /* Get the GH extensions for IOBasic */
-  myGH = (iobasicGH *) GH->extensions [CCTK_GHExtensionHandle ("IOBasic")];
+  myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
 
   CheckSteerableParameters (myGH);
 
@@ -68,7 +66,7 @@ int IOBasic_OutputGH (cGH *GH)
   {
 
     /* Is it time for output ? */
-    if (! IOBasic_TimeForOutput (GH, vindex))
+    if (! IOBasic_TimeForScalarOutput (GH, vindex))
     {
       continue;
     }
@@ -76,8 +74,8 @@ int IOBasic_OutputGH (cGH *GH)
     /* Get the variable name for this index (for filename) */
     name = CCTK_VarName (vindex);
 
-#ifdef IO_DEBUG
-    printf("\nIn IOBasic_OutputGH\n----------------\n");
+#ifdef IOBASIC_DEBUG
+    printf("\nIn IOBasic_ScalarOutputGH\n----------------\n");
     printf("  Index = %d\n",vindex);
     printf("  Variable = -%s-\n",name);
     printf("  Last output iteration was = %d\n",myGH->outScalar_last[vindex]);
@@ -86,11 +84,11 @@ int IOBasic_OutputGH (cGH *GH)
     /* Make the IO call */
     if (CCTK_GroupTypeFromVarI (vindex) == CCTK_SCALAR)
     {
-      IOBasic_Write (GH, vindex, name);
+      IOBasic_WriteScalarGS (GH, vindex, name);
     }
     else
     {
-      IOBasic_WriteGF (GH, vindex, name);
+      IOBasic_WriteScalarGA (GH, vindex, name);
     }
 
     /* Register GF as having 0D output this iteration */
@@ -103,13 +101,13 @@ int IOBasic_OutputGH (cGH *GH)
 
 
 /*@@
-   @routine    IOBasic_OutputVarAs
+   @routine    IOBasic_ScalarOutputVarAs
    @date       Sat March 6 1999
    @author     Gabrielle Allen
    @desc
    unconditional output of a variable using the IOBasic output method
    @enddesc
-   @calledby IOBasic_OutputGH, CCTK_OutputVarAsByMethod ("IOBasic")
+   @calledby IOBasic_ScalarOutputGH, CCTK_OutputVarAsByMethod ("IOBasic")
    @var     GH
    @vdesc   Pointer to CCTK GH
    @vtype   cGH
@@ -129,15 +127,15 @@ int IOBasic_OutputGH (cGH *GH)
    @vcomment
    @endvar
 @@*/
-int IOBasic_OutputVarAs (cGH *GH, const char *fullname, const char *alias)
+int IOBasic_ScalarOutputVarAs (cGH *GH, const char *fullname, const char *alias)
 {
   int vindex;
 
 
   vindex = CCTK_VarIndex (fullname);
 
-#ifdef IO_DEBUG
-  printf("\nIn IOBasic_OutputVarAs\n-------------------\n");
+#ifdef IOBASIC_DEBUG
+  printf("\nIn IOBasic_ScalarOutputVarAs\n-------------------\n");
   printf("  Fullname = -%s-\n",fullname);
   printf("  Alias = -%s-\n",alias);
   printf("  Index = %d\n",vindex);
@@ -145,11 +143,11 @@ int IOBasic_OutputVarAs (cGH *GH, const char *fullname, const char *alias)
 
   if (CCTK_GroupTypeFromVarI (vindex) == CCTK_SCALAR)
   {
-    IOBasic_Write (GH, vindex, alias);
+    IOBasic_WriteScalarGS (GH, vindex, alias);
   }
   else
   {
-    IOBasic_WriteGF (GH, vindex, alias);
+    IOBasic_WriteScalarGA (GH, vindex, alias);
   }
 
   return (0);
@@ -157,14 +155,14 @@ int IOBasic_OutputVarAs (cGH *GH, const char *fullname, const char *alias)
 
 
  /*@@
-   @routine    IOBasic_TimeForOutput
+   @routine    IOBasic_TimeForScalarOutput
    @date       Sat March 6 1999
    @author     Gabrielle Allen
    @desc 
    Decides if it is time to output a variable using Scalar output
    method
    @enddesc 
-   @calls    CCTK_GHExtensionHandle 
+   @calls    CCTK_GHExtension
              CCTK_GroupTypeFromVar
              CCTK_WARN
    @calledby   
@@ -184,8 +182,7 @@ int IOBasic_OutputVarAs (cGH *GH, const char *fullname, const char *alias)
    @vcomment 
    @endvar 
 @@*/
-                  
-int IOBasic_TimeForOutput (cGH *GH, int vindex)
+int IOBasic_TimeForScalarOutput (cGH *GH, int vindex)
 {
   int return_type;
   iobasicGH *myGH;
@@ -196,7 +193,7 @@ int IOBasic_TimeForOutput (cGH *GH, int vindex)
   return_type = 0;
 
   /* Get the GH extension for IOBasic */
-  myGH = (iobasicGH *) GH->extensions [CCTK_GHExtensionHandle ("IOBasic")];
+  myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
 
   CheckSteerableParameters (myGH);
 
@@ -230,7 +227,7 @@ int IOBasic_TimeForOutput (cGH *GH, int vindex)
 
 
 /*@@
-   @routine    IOBasic_TriggerOutput
+   @routine    IOBasic_TriggerScalarOutput
    @date       Sat March 6 1999
    @author     Gabrielle Allen
    @desc
@@ -252,19 +249,19 @@ int IOBasic_TimeForOutput (cGH *GH, int vindex)
    @vcomment
    @endvar
 @@*/
-int IOBasic_TriggerOutput (cGH *GH, int vindex)
+int IOBasic_TriggerScalarOutput (cGH *GH, int vindex)
 {
   const char *name;
   iobasicGH *myGH;
 
 
   /* Get the GH extension for IOBasic */
-  myGH = (iobasicGH *) GH->extensions [CCTK_GHExtensionHandle ("IOBasic")];
-  
+  myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
+
   name = CCTK_VarName (vindex);
 
-#ifdef IO_DEBUG
-  printf ("\nIn IOBasic_TriggerOutput\n---------------------\n");
+#ifdef IOBASIC_DEBUG
+  printf ("\nIn IOBasic_TriggerScalarOutput\n---------------------\n");
   printf ("  Index = %d\n", vindex);
   printf ("  Variable = -%s-\n", name);
 #endif
@@ -272,11 +269,11 @@ int IOBasic_TriggerOutput (cGH *GH, int vindex)
   /* Do the Scalar output */
   if (CCTK_GroupTypeFromVarI (vindex) == CCTK_SCALAR)
   {
-    IOBasic_Write (GH, vindex, name);
+    IOBasic_WriteScalarGS (GH, vindex, name);
   }
   else
   {
-    IOBasic_WriteGF (GH, vindex, name);
+    IOBasic_WriteScalarGA (GH, vindex, name);
   }
 
   /* Register variable as having Scalar output this iteration */
@@ -290,29 +287,18 @@ int IOBasic_TriggerOutput (cGH *GH, int vindex)
 /* check if steerable parameters have changed */
 static void CheckSteerableParameters (iobasicGH *myGH)
 {
+  DECLARE_CCTK_PARAMETERS
   int times_set;
-  int out_old;
-  int i;
   static int outScalar_vars_lastset = -1;
-  DECLARE_CCTK_PARAMETERS
 
 
   /* How often to output */
-  out_old = myGH->outScalar_every;
   myGH->outScalar_every = out_every > 0 ? out_every : -1;
   if (outScalar_every > 0)
   {
     myGH->outScalar_every = outScalar_every;
   }
-  if (myGH->outScalar_every != out_old)
-  {
-    if (CCTK_Equals(newverbose,"standard") || CCTK_Equals(newverbose,"full"))
-    {
-      CCTK_VInfo("IOBasic","Scalar: Output every %d iterations",
-		 myGH->outScalar_every);
-    }
-  }
-    
+
   /* re-parse the 'outScalar_vars' parameter if it was changed */
   times_set = CCTK_ParameterQueryTimesSet ("outScalar_vars", CCTK_THORNSTRING);
   if (times_set != outScalar_vars_lastset)
@@ -321,18 +307,6 @@ static void CheckSteerableParameters (iobasicGH *myGH)
     CCTK_TraverseString (outScalar_vars, SetOutputFlag, myGH->do_outScalar,
                          CCTK_GROUP_OR_VAR);
 
-    if (CCTK_Equals(newverbose,"full"))
-    {
-      for (i=0;i<CCTK_NumVars();i++)
-      {
-	if (myGH->do_outScalar[i] > 0)
-	{
-	  CCTK_VInfo("IOBasic","Scalar: Output requested for %s",
-		     CCTK_VarName(i));
-	}
-      }
-    }
-
     /* Save the last setting of 'outScalar_vars' parameter */
     outScalar_vars_lastset = times_set;
   }
diff --git a/src/Startup.c b/src/Startup.c
index 43637c3..b6b6068 100644
--- a/src/Startup.c
+++ b/src/Startup.c
@@ -2,90 +2,193 @@
    @file      Startup.c
    @date      Friday 18th September 1999
    @author    Gabrielle Allen
-   @desc 
-   Startup routines for IOBasic.
-   @enddesc 
+   @desc
+              Startup routines for IOBasic.
+   @enddesc
+   @version   $Id$
  @@*/
 
-
 #include <stdio.h>
 #include <string.h>
+#include <stdlib.h>
 
 #include "cctk.h"
 #include "cctk_Parameters.h"
+#include "iobasicGH.h"
 
 static const char *rcsid = "$Header$";
 
 CCTK_FILEVERSION(CactusBase_IOBasic_Startup_c)
 
-void IOBasic_Startup (void);
 
-/* prototypes of functions to be registered */
-int IOBasic_OutputGH (cGH *GH);
-int IOBasic_TriggerOutput (cGH *GH, int);
-int IOBasic_TimeForOutput (cGH *GH, int);
-int IOBasic_OutputVarAs (cGH *GH, const char *var, const char *alias);
-void *IOBasic_SetupGH (tFleshConfig *config, int convergence_level, cGH *GH);
-int IOBasic_InitGH (cGH *GH);
+/********************************************************************
+ ********************    External Routines   ************************
+ ********************************************************************/
+void IOBasic_Startup (void);
 
-int IOBasic_OutputInfoGH (cGH *GH);
-int IOBasic_TriggerOutputInfo (cGH *GH, int);
-int IOBasic_TimeForInfo (cGH *GH, int);
+/********************************************************************
+ ********************    Internal Routines   ************************
+ ********************************************************************/
+static void *IOBasic_SetupGH (tFleshConfig *config,
+                              int convergence_level,
+                              cGH *GH);
 
 
  /*@@
-   @routine    IOBasic_Startup
-   @date       Friday 18th September 1999
-   @author     Gabrielle Allen
-   @desc 
-   The startup registration routine for Basic IO.
-   Registers the GH extensions needed for IO and
-   the registerable routines used for each method of IO.
-   IO does not overload any functions.
-   @enddesc 
-   @calls     
-   @calledby   
-   @history 
- 
-   @endhistory 
-
+   @routine   IOBasic_Startup
+   @date      Friday 18th September 1999
+   @author    Gabrielle Allen
+   @desc
+              The startup registration routine for IOBasic.
+              Registers the GH extensions needed for IOBasic
+              along with its setup routine.
+   @enddesc
+   @calls     CCTK_RegisterGHExtensionSetupGH
 @@*/
 void IOBasic_Startup (void)
 {
-  int IOMethod;
-  int IO_GHExtension;
-  DECLARE_CCTK_PARAMETERS
-
   if (CCTK_GHExtensionHandle ("IO") < 0)
   {
     CCTK_WARN (1, "Thorn IOUtil was not activated. "
-                  "No IOBasic IO methods will be enabled.");
+                  "No IOBasic I/O methods will be enabled.");
     return;
   }
 
-  IO_GHExtension = CCTK_RegisterGHExtension ("IOBasic");
-  CCTK_RegisterGHExtensionSetupGH (IO_GHExtension, IOBasic_SetupGH);
-  CCTK_RegisterGHExtensionInitGH (IO_GHExtension, IOBasic_InitGH);
+  CCTK_RegisterGHExtensionSetupGH (CCTK_RegisterGHExtension ("IOBasic"),
+                                   IOBasic_SetupGH);
+}
 
-  /* Register the IOBasic routines as output methods  */
-  IOMethod = CCTK_RegisterIOMethod ("Scalar");
-  CCTK_RegisterIOMethodOutputGH (IOMethod, IOBasic_OutputGH);
-  CCTK_RegisterIOMethodOutputVarAs (IOMethod, IOBasic_OutputVarAs);
-  CCTK_RegisterIOMethodTimeToOutput (IOMethod, IOBasic_TimeForOutput);
-  CCTK_RegisterIOMethodTriggerOutput (IOMethod, IOBasic_TriggerOutput);
 
-  IOMethod = CCTK_RegisterIOMethod ("Info");
-  CCTK_RegisterIOMethodOutputGH (IOMethod, IOBasic_OutputInfoGH);
-  CCTK_RegisterIOMethodTimeToOutput (IOMethod, IOBasic_TimeForInfo);
-  CCTK_RegisterIOMethodTriggerOutput (IOMethod, IOBasic_TriggerOutputInfo);
+/****************************************************************************/
+/*                           local routines                                 */
+/****************************************************************************/
+ /*@@
+   @routine   IOBasic_SetupGH
+   @date      Sat Feb 6 1999
+   @author    Gabrielle Allen
+   @desc
+              Allocates and sets up IOBasic's GH extension structure
+   @enddesc
+
+   @calls     CCTK_RegisterIOMethod
+              CCTK_RegisterIOMethodOutputGH
+              CCTK_RegisterIOMethodOutputVarAs
+              CCTK_RegisterIOMethodTimeToOutput
+              CCTK_RegisterIOMethodTriggerOutput
+
+   @var       config
+   @vdesc     the CCTK configuration as provided by the flesh
+   @vtype     tFleshConfig *
+   @vio       unused
+   @endvar
+   @var       convergence_level
+   @vdesc     the convergence level
+   @vtype     int
+   @vio       unused
+   @endvar
+   @var       GH
+   @vdesc     Pointer to CCTK grid hierarchy
+   @vtype     cGH *
+   @vio       in
+   @endvar
+
+   @returntype  void *
+   @returndesc
+                pointer to the allocated GH extension structure
+   @endreturndesc
+@@*/
+static void *IOBasic_SetupGH (tFleshConfig *config,
+                              int convergence_level,
+                              cGH *GH)
+{
+  DECLARE_CCTK_PARAMETERS
+  int i;
+  iobasicGH *newGH;
+
 
-  if (CCTK_Equals(newverbose,"standard") || CCTK_Equals(newverbose,"full"))
+  /* suppress compiler warnings about unused variables */
+  config = config;
+  convergence_level = convergence_level;
+  GH = GH;
+
+  /* allocate the GH extension and its components */
+  newGH = (iobasicGH *) malloc (sizeof (iobasicGH));
+  if (newGH)
   {
-    CCTK_INFO("IO Method <Scalar> registered");
-    CCTK_INFO("Scalar: Output of scalar quantities "
-	      "(grid scalars, reductions) to ASCII file");
-    CCTK_INFO("IO Method <Info> registered");
-    CCTK_INFO("Info: Output of reductions of grid functions to screen");
+    /* Register the IOBasic routines as output methods  */
+    i = CCTK_RegisterIOMethod ("Scalar");
+    CCTK_RegisterIOMethodOutputGH (i, IOBasic_ScalarOutputGH);
+    CCTK_RegisterIOMethodOutputVarAs (i, IOBasic_ScalarOutputVarAs);
+    CCTK_RegisterIOMethodTimeToOutput (i, IOBasic_TimeForScalarOutput);
+    CCTK_RegisterIOMethodTriggerOutput (i, IOBasic_TriggerScalarOutput);
+
+    i = CCTK_RegisterIOMethod ("Info");
+    CCTK_RegisterIOMethodOutputGH (i, IOBasic_InfoOutputGH);
+    CCTK_RegisterIOMethodTimeToOutput (i, IOBasic_TimeForInfoOutput);
+    CCTK_RegisterIOMethodTriggerOutput (i, IOBasic_TriggerInfoOutput);
+
+    if (CCTK_Equals (newverbose, "standard") ||
+        CCTK_Equals( newverbose, "full"))
+    {
+      CCTK_INFO ("I/O Method 'Scalar' registered");
+      CCTK_INFO ("Scalar: Output of scalar quantities (grid scalars, "
+                 "reductions) to ASCII files");
+      CCTK_INFO ("I/O Method 'Info' registered");
+      CCTK_INFO ("Info: Output of scalar quantities (grid scalars, "
+                 "reductions) to screen");
+    }
+
+    i = CCTK_NumVars ();
+
+    newGH->info_reductions = (iobasic_reductionlist_t *)
+                             calloc (i, sizeof (iobasic_reductionlist_t));
+    newGH->do_outScalar   = (char *) malloc (i * sizeof (char));
+    newGH->outInfo_last   = (int *)  malloc (i * sizeof (int));
+    newGH->outScalar_last = (int *)  malloc (i * sizeof (int));
+
+    memset (newGH->outInfo_last,   -1, i * sizeof (int));
+    memset (newGH->outScalar_last, -1, i * sizeof (int));
+
+    newGH->filenameListScalar = NULL;
+
+    /* Check whether "IOBasic::outdirScalar" was set.
+       If so take this dir otherwise default to "IO::outdir" */
+    if (CCTK_ParameterQueryTimesSet ("outdirScalar", CCTK_THORNSTRING) <= 0)
+    {
+      outdirScalar = outdir;
+    }
+    /* skip the directory pathname if output goes into current directory */
+    if (strcmp (outdirScalar, "."))
+    {
+      i = strlen (outdirScalar);
+      newGH->outdirScalar = (char *) malloc (i + 2);
+      strcpy (newGH->outdirScalar, outdirScalar);
+      newGH->outdirScalar[i] = '/';
+      newGH->outdirScalar[i+1] = 0;
+    }
+    else
+    {
+      newGH->outdirScalar = "";
+    }
+
+    /* create the output dir */
+    if (*newGH->outdirScalar && CCTK_MyProc (GH) == 0)
+    {
+      i = CCTK_CreateDirectory (0755, newGH->outdirScalar);
+      if (i < 0)
+      {
+        CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
+                    "IOBasic_SetupGH: Couldn't create Scalar output directory "
+                    "'%s'", newGH->outdirScalar);
+      }
+      else if (i > 0)
+      {
+        CCTK_VWarn (2, __LINE__, __FILE__, CCTK_THORNSTRING,
+                    "IOBasic_InitGH: Scalar output directory '%s' already "
+                    "exists", newGH->outdirScalar);
+      }
+    }
   }
-  
+
+  return (newGH);
 }
diff --git a/src/Write.c b/src/Write.c
deleted file mode 100644
index ba1a4c4..0000000
--- a/src/Write.c
+++ /dev/null
@@ -1,185 +0,0 @@
-/*@@
-   @routine    Write.c
-   @date       18th September 1999
-   @author     Gabrielle Allen
-   @desc 
-   Writes scalar grid variable data.
-   @enddesc 
-   @calls    
-   @calledby   
-   @history
-   @hauthor  @hdate 
-   @hdesc 
-   @hendhistory
-@@*/
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>      /* strlen(3) */
-#include <sys/types.h>
-#include <sys/stat.h>    /* stat(2) */
-
-#include "cctk.h"
-#include "cctk_Parameters.h"
-#include "CactusBase/IOUtil/src/ioutil_AdvertisedFiles.h"
-#include "CactusBase/IOUtil/src/ioutil_CheckpointRecovery.h"
-#include "iobasicGH.h"
-
-static const char *rcsid = "$Header$";
-
-CCTK_FILEVERSION(CactusBase_IOBasic_Write_c)
-
-void IOBasic_Write (cGH *GH, int vindex, const char *alias)
-{
-  DECLARE_CCTK_PARAMETERS
-  char *openmode;
-  FILE *file;
-  void *data;
-  char *fname, buffer[128];
-  iobasicGH *myGH;
-  char format_str_real[15], format_str_int[15];
-  struct stat fileinfo;
-
-
-  /* output is done by processor 0 only */
-  if (CCTK_MyProc (GH) != 0) 
-  {
-    return;
-  }
-
-  /* first, check if variable has storage assigned */
-  if (! CCTK_QueryGroupStorageI (GH, CCTK_GroupIndexFromVarI (vindex)))
-  {
-    char *fullname;
-
-    fullname = CCTK_FullName (vindex);
-    CCTK_VWarn (2, __LINE__, __FILE__, CCTK_THORNSTRING,
-                "IOBasic_Write: No scalar output for '%s' (no storage)", 
-		fullname);
-    free (fullname);
-    return;
-  }
-
-  /* set the output format string for the desired notation */
-  sprintf (format_str_real, "%%%s\t%%%s\n", out_format, out_format);
-  sprintf (format_str_int,  "%%%s\t%%d\n", out_format);
-
-  /* get the GH extensions for IOBasic */
-  myGH = (iobasicGH *) GH->extensions [CCTK_GHExtensionHandle ("IOBasic")];
-
-  /* build the output filename */
-  /* skip the pathname if output goes into current directory */
-  fname = (char *) malloc (strlen (myGH->outdirScalar) + strlen (alias) + 5);
-  if (strcmp (myGH->outdirScalar, "."))
-  {
-    sprintf (fname, "%s/%s.tl", myGH->outdirScalar, alias);
-  }
-  else
-  {
-    sprintf (fname, "%s.tl", alias);
-  }
-
-  /* see if output files for this alias name were already created */
-  if (GetNamedData (myGH->filenameListScalar, fname) == NULL)
-  {
-    /* if restart from recovery, all existing files are opened
-       in append mode */
-    if (IOUtil_RestartFromRecovery (GH))
-      openmode = stat (fname, &fileinfo) == 0 ? "a" : "w";
-    else
-      openmode = "w";
-  }
-  else
-  {
-    openmode = "a";
-  }
-
-  /* open the output file with the given mode */
-  file = fopen (fname, openmode);
-  if (file == NULL)
-  {
-    CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
-                "Could not open output file '%s'", fname);
-    free (fname);
-    return;
-  }
-
-  if (*openmode == 'w')
-  {
-    char comment_char;
-    ioAdvertisedFileDesc advertised_file; 
-
-    if (CCTK_Equals (outScalar_style, "gnuplot")) 
-    {
-      comment_char = '#';
-      advertised_file.mimetype = "application/gnuplot";
-    }
-    else
-    {
-      comment_char = '"';    /* this is for xgraph */
-      advertised_file.mimetype = "application/x-graph";
-    }
-
-    /* just store a non-NULL pointer in database */
-    StoreNamedData (&myGH->filenameListScalar, fname, (void *) 1);
-
-    /* advertise the file for downloading */
-    advertised_file.slice = "tl";
-    advertised_file.thorn = CCTK_THORNSTRING;
-    advertised_file.varname = CCTK_FullName (vindex);
-    advertised_file.description = "Scalar value";
-
-    IOUtil_AdvertiseFile (GH, fname, &advertised_file);
-
-    /* write the file info and the header */
-    if (CCTK_Equals (out_fileinfo, "parameter filename") ||
-        CCTK_Equals (out_fileinfo, "all"))
-    {
-      buffer[0] = 0;
-      CCTK_ParameterFilename (sizeof (buffer), buffer);
-      fprintf (file, "%cParameter file %s\n", comment_char, buffer);
-    }
-    if (CCTK_Equals (out_fileinfo, "creation date") ||
-        CCTK_Equals (out_fileinfo, "all"))
-    {
-      buffer[0] = 0;
-      Util_CurrentDate (sizeof (buffer), buffer);
-      fprintf (file, "%cCreated %s ", comment_char, buffer);
-      Util_CurrentTime (sizeof (buffer), buffer);
-      fprintf (file, "%s\n", buffer);
-    }
-    if (CCTK_Equals (out_fileinfo, "axis labels") ||
-        CCTK_Equals (out_fileinfo, "all"))
-    {
-      fprintf (file, "%cx-label time\n", comment_char);
-      fprintf (file, "%cy-label %s\n", comment_char, advertised_file.varname);
-    }
-    fprintf (file, "%c%s v time\n", comment_char, alias);
-
-    free (advertised_file.varname);
-  }
-
-  /* get the data pointer */
-  data = CCTK_VarDataPtrI (GH, 0, vindex); 
-
-  switch (CCTK_VarTypeI (vindex))
-  {
-    case CCTK_VARIABLE_REAL:
-      fprintf (file, format_str_real, GH->cctk_time,
-               (double) *(CCTK_REAL *) data);
-      break;
-    case CCTK_VARIABLE_INT:
-      fprintf (file, format_str_int, GH->cctk_time,
-               (int) *(CCTK_INT *) data);
-      break;
-    default:
-      CCTK_WARN (3, "Unsupported data type");
-      break;
-  }
-
-  /* close the output file */
-  fclose (file);
-
-  /* clean up */
-  free (fname);
-}
diff --git a/src/WriteGF.c b/src/WriteGF.c
deleted file mode 100644
index ef7378b..0000000
--- a/src/WriteGF.c
+++ /dev/null
@@ -1,306 +0,0 @@
-/*@@
-   @routine    WriteGF
-   @date       Tue Apr  1 16:45:35 1997
-   @author     Paul Walker
-   @desc 
-               Dumps the scalar data of CCTK_ARRAY and CCTK_GF variables.
-   @enddesc 
-   @version   $Id$
-@@*/
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>      /* strlen(3) */
-#include <ctype.h>       /* isalpha(3) */
-#include <sys/types.h>
-#include <sys/stat.h>    /* stat(2) */
-
-#include "cctk.h"
-#include "cctk_Parameters.h"
-#include "CactusBase/IOUtil/src/ioutil_AdvertisedFiles.h"
-#include "CactusBase/IOUtil/src/ioutil_CheckpointRecovery.h"
-#include "iobasicGH.h"
-
-
-/* the rcs ID and its dummy function to use it */
-static const char *rcsid = "$Id$";
-CCTK_FILEVERSION(CactusBase_IOBasic_WriteGF_c)
-
-
- /*@@
-   @routine   IOBasic_WriteGF
-   @date      Mon Jun 19 2000
-   @author    Thomas Radke
-   @desc
-              Apply the given reduction operators on the CCTK_ARRAY or
-              CCTK_GF variable and output the result into a text file
-              suitable for postprocessing by either gluplot or xgraph.
-   @enddesc
-
-   @calls     CCTK_QueryGroupStorageI
-              CCTK_Reduce
-              CCTK_ReductionHandle
-              IOUtil_RestartFromRecovery
-              IOUtil_AdvertiseFile
-
-   @var       GH
-   @vdesc     Pointer to CCTK grid hierarchy
-   @vtype     cGH *
-   @vio       in
-   @endvar
-   @var       vindex
-   @vdesc     CCTK index of the variable to output
-   @vtype     int
-   @vio       in
-   @endvar
-   @var       alias
-   @vdesc     alias name to use for building the output filename
-   @vtype     const char *
-   @vio       in
-   @endvar
-@@*/
-void IOBasic_WriteGF (cGH *GH,
-                      int vindex,
-                      const char *alias)
-{
-  DECLARE_CCTK_PARAMETERS
-  int ierr;
-  int reduction_handle;
-  iobasicGH *myGH;
-  FILE *file;
-  char *openmode;
-  char *filename;
-  char *reduction_op;
-  char *string_start;
-  char *string_end;
-  char comment_char;
-  char format_str[15];
-  const char *file_extension;
-  char *fullname, buffer[128];
-  struct stat fileinfo;
-  ioAdvertisedFileDesc advertised_file;
-  CCTK_REAL reduction_value;
-  union
-  {
-    char *non_const_ptr;
-    const char *const_ptr;
-  } reductions;
-
-
-  /* this union helps us to avoid compiler warning about discarding
-     the const qualifier from a pointer target type */
-  reductions.const_ptr = outScalar_reductions;
-
-  /* first, check if variable has storage assigned */
-  if (! CCTK_QueryGroupStorageI (GH, CCTK_GroupIndexFromVarI (vindex)))
-  {
-    fullname = CCTK_FullName (vindex);
-    CCTK_VWarn (2, __LINE__, __FILE__, CCTK_THORNSTRING,
-                "IOBasic_WriteGF: No scalar output for '%s' (no storage)", 
-                fullname);
-    free (fullname);
-    return;
-  }
-
-  /* set output format */
-  sprintf (format_str, "%%%s\t%%%s\n", out_format, out_format);
-
-  /* set the output file extension and the output style */
-  if (CCTK_Equals (outScalar_style, "gnuplot"))
-  {
-    file_extension = ".asc";
-    comment_char = '#';
-  }
-  else
-  {
-    file_extension = ".xg";
-    comment_char = '"';
-  }
-
-  /* get the GH extension handle for IOBasic */
-  myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
-
-  /* allocate strings for the filename and the reduction operator */
-  filename = (char *) malloc (strlen (myGH->outdirScalar) + strlen (alias) +
-                              strlen (reductions.const_ptr) +
-                              strlen (file_extension) + 3);
-  reduction_op = (char *) malloc (strlen (reductions.const_ptr) + 1);
-
-  /* now loop over all reduction operators */
-  string_start = reductions.non_const_ptr;
-  while (string_start && *string_start)
-  {
-    /* skip leading spaces */
-    while (isspace (*string_start))
-    {
-      string_start++;
-    }
-    if (! *string_start)
-    {
-      break;
-    }
-
-    /* advance to end of the operator string */
-    string_end = string_start + 1;
-    while (*string_end && ! isspace (*string_end))
-    {
-      string_end++;
-    }
-
-    /* copy the operator string */
-    strncpy (reduction_op, string_start, string_end - string_start);
-    reduction_op[string_end - string_start] = 0;
-    string_start = string_end;
-
-    /* get the reduction handle from the reduction operator */
-    reduction_handle = CCTK_ReductionHandle (reduction_op);
-    if (reduction_handle < 0) 
-    {
-      CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
-                  "IOBasic_WriteGF: Invalid reduction operator '%s'", 
-                  reduction_op);
-      continue;
-    }
-
-    /* do the reduction (all processors) */
-    ierr = CCTK_Reduce (GH, 0, reduction_handle, 1, CCTK_VARIABLE_REAL,
-                        &reduction_value, 1, vindex);
-
-    /* dump the reduction value to file by processor 0 */
-    if (ierr == 0 && CCTK_MyProc (GH) == 0)
-    {
-
-      /* build the filename */
-      if (new_filename_scheme)
-      {
-        /* skip the pathname if output goes into current directory */
-        if (strcmp (myGH->outdirScalar, "."))
-        {
-          sprintf (filename, "%s/%s_%s%s", myGH->outdirScalar, alias,
-                                           reduction_op, file_extension);
-        }
-        else
-        {
-          sprintf (filename, "%s_%s%s", alias, reduction_op, file_extension);
-        }
-      }
-      else
-      {
-        /* FIXME: this check can go if we switch to the new filename scheme */
-        if (strcmp (reduction_op, "minimum") == 0)
-        {
-          file_extension = "min";
-        }
-        else if (strcmp (reduction_op, "maximum") == 0)
-        {
-          file_extension = "max";
-        }
-        else if (strcmp (reduction_op, "norm1") == 0)
-        {
-          file_extension = "nm1";
-        }
-        else if (strcmp (reduction_op, "norm2") == 0)
-        {
-          file_extension = "nm2";
-        }
-        else
-        {
-          file_extension = "unknown";
-        }
-        /* skip the pathname if output goes into current directory */
-        if (strcmp (myGH->outdirScalar, "."))
-        {
-          sprintf (filename, "%s/%s_%s.tl", myGH->outdirScalar, alias,
-                                            file_extension);
-        }
-        else
-        {
-          sprintf (filename, "%s_%s.tl", alias, file_extension);
-        }
-      }
-
-      /* see if output files for this alias name were already created */
-      if (GetNamedData (myGH->filenameListScalar, filename) == NULL)
-      {
-        /* if restart from recovery, all existing files are opened
-           in append mode */
-        if (IOUtil_RestartFromRecovery (GH))
-        {
-          openmode = stat (filename, &fileinfo) == 0 ? "a" : "w";
-        }
-        else
-        {
-          openmode = "w";
-        }
-      }
-      else
-      {
-        openmode = "a";
-      }
-
-      file = fopen (filename, openmode);
-      if (file == NULL)
-      {
-        CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
-                    "IOBasic_WriteGF: Could not open output file '%s'", 
-                    filename);
-        continue;
-      }
-
-      /* when creating the file, advertise it for downloading,
-         write the header and the file info,
-         and save the filename in the database */
-      if (*openmode == 'w')
-      {
-        /* advertise the file for downloading */
-        advertised_file.slice       = reduction_op;
-        advertised_file.thorn       = CCTK_THORNSTRING;
-        advertised_file.varname     = CCTK_FullName (vindex);
-        advertised_file.description = "Reduction on Grid Functions";
-        advertised_file.mimetype    = CCTK_Equals (outScalar_style, "gnuplot") ?
-                                  "application/gnuplot" : "application/x-graph";
-
-        IOUtil_AdvertiseFile (GH, filename, &advertised_file);
-
-        if (CCTK_Equals (out_fileinfo, "parameter filename") ||
-            CCTK_Equals (out_fileinfo, "all"))
-        {
-          buffer[0] = 0;
-          CCTK_ParameterFilename (sizeof (buffer), buffer);
-          fprintf (file, "%cParameter file %s\n", comment_char, buffer);
-        }
-        if (CCTK_Equals (out_fileinfo, "creation date") ||
-            CCTK_Equals (out_fileinfo, "all"))
-        { 
-          buffer[0] = 0;
-          Util_CurrentDate (sizeof (buffer), buffer);
-          fprintf (file, "%cCreated %s ", comment_char, buffer);
-          Util_CurrentTime (sizeof (buffer), buffer);
-          fprintf (file, "%s\n", buffer);
-        }
-        if (CCTK_Equals (out_fileinfo, "axis labels") ||
-            CCTK_Equals (out_fileinfo, "all"))
-        {
-          fprintf (file, "%cx-label time\n", comment_char);
-          fprintf (file, "%cy-label %s\n",
-                   comment_char, advertised_file.varname);
-        }
-        fprintf (file, "%c%s %s v time\n", comment_char, alias,
-                 reduction_op);
-
-        free (advertised_file.varname);
-
-        /* just store a non-NULL pointer in database */
-        StoreNamedData (&myGH->filenameListScalar, filename, (void *) 1);
-      }
-
-      /* write the data and close the file */
-      fprintf (file, format_str, GH->cctk_time, reduction_value);
-      fclose (file);
-    }
-  }
-
-  /* free allocated resources */
-  free (reduction_op);
-  free (filename);
-}
diff --git a/src/WriteInfo.c b/src/WriteInfo.c
index 4c22f9e..3345161 100644
--- a/src/WriteInfo.c
+++ b/src/WriteInfo.c
@@ -1,71 +1,168 @@
 /*@@
-   @routine    WriteInfo
-   @date       June 31 1999
-   @author     Gabrielle Allen, Paul Walker
-   @desc 
-   Dumps the Info data.
-   @enddesc 
-   @calls    
-   @calledby   
-   @history
-   @hauthor Thomas Radke @hdate 17 Mar 1999
-   @hdesc included "cctk_Comm.h" to overload CCTK_MyProc() properly
-   @hendhistory
+   @file      WriteInfo.c
+   @date      June 31 1999
+   @author    Gabrielle Allen, Paul Walker, Thomas Radke
+   @desc
+              Gets the data for IOBasic's info output.
+   @enddesc
+   @version   $Id: /cactusdevcvs/CactusBase/IOBasic/src/OutputInfo.c,v 1.24 2001
 @@*/
 
-#include <stdio.h>
 #include <stdlib.h>
 
 #include "cctk.h"
+#include "iobasicGH.h"
 
+/* the rcs ID and its dummy function to use it */
 static const char *rcsid = "$Header$";
-
 CCTK_FILEVERSION(CactusBase_IOBasic_WriteInfo_c)
 
-int IOBasic_WriteInfo (cGH *GH, 
-                       CCTK_REAL *val, 
-                       int index, 
-                       const char *operator, 
-                       const char *alias)
+
+ /*@@
+   @routine    IOBasic_WriteInfo
+   @date       Tue 31 July 2001
+   @author     Thomas Radke
+   @desc
+               Gets the data values to output for a given CCTK variable.
+               For CCTK_SCALAR variables, their value is taken,
+               for CCTK_GF and CCTK_ARRAY variables the appropriate
+               reduction operations are performed and their results taken.
+   @enddesc
+
+   @calls      CCTK_VarDataPtrI
+               CCTK_Reduce
+@@*/
+void IOBasic_WriteInfo (cGH *GH, int vindex)
 {
-  int ierr;
-  int reduce_handle;
-  int retval = 0;
+  int vtype;
+  char *fullname;
+  iobasicGH *myGH;
+  void *ptr;
+  iobasic_reduction_t *reduction;
+
+
+  myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
+  reduction = myGH->info_reductions[vindex].reductions;
 
   /* first, check if variable has storage assigned */
-  if (! CCTK_QueryGroupStorageI (GH, CCTK_GroupIndexFromVarI (index))) 
+  if (! CCTK_QueryGroupStorageI (GH, CCTK_GroupIndexFromVarI (vindex)))
   {
-    char *fullname;
-
-    fullname = CCTK_FullName (index);
+    fullname = CCTK_FullName (vindex);
     CCTK_VWarn (2, __LINE__, __FILE__, CCTK_THORNSTRING,
-                "IOBasic_WriteInfo: No info output for '%s' (no storage)", 
+                "IOBasic_WriteInfo: No info output for '%s' (no storage)",
                 fullname);
     free (fullname);
-    return -3;
+    /* invalidate data buffer for this variable */
+    while (reduction)
+    {
+      reduction->is_valid = 0;
+      reduction = reduction->next;
+    }
+    return;
   }
 
-  reduce_handle = CCTK_ReductionHandle(operator);
-
-  if (reduce_handle > -1)
+  /* CCTK scalars are printed by their value, cast into a C double */
+  if (CCTK_GroupTypeFromVarI (vindex) == CCTK_SCALAR)
   {
-    ierr = CCTK_Reduce(GH, 0, reduce_handle, 1, CCTK_VARIABLE_REAL, val,
-                       1, index);
-    if (ierr < 0)
+    reduction->is_valid = 1;
+
+    /* get the variable's data type and data pointer */
+    ptr = CCTK_VarDataPtrI (GH, 0, vindex);
+    vtype = CCTK_VarTypeI (vindex);
+    if (vtype == CCTK_VARIABLE_CHAR)
+    {
+      reduction->value = (double) *(CCTK_CHAR *) ptr;
+    }
+    else if (vtype == CCTK_VARIABLE_INT)
+    {
+      reduction->value = (double) *(CCTK_INT *) ptr;
+    }
+    else if (vtype == CCTK_VARIABLE_REAL)
+    {
+      reduction->value = (double) *(CCTK_REAL *) ptr;
+    }
+    else if (vtype == CCTK_VARIABLE_COMPLEX)
+    {
+      reduction->value = (double) ((CCTK_REAL *) ptr)[0];
+      reduction->next->value = (double) ((CCTK_REAL *) ptr)[1];
+      reduction->next->is_valid = 1;
+    }
+#ifdef CCTK_INT2
+    else if (vtype == CCTK_VARIABLE_INT2)
+    {
+      reduction->value = (double) *(CCTK_INT2 *) ptr;
+    }
+#endif
+#ifdef CCTK_INT4
+    else if (vtype == CCTK_VARIABLE_INT4)
     {
-      CCTK_VWarn(1, __LINE__, __FILE__, CCTK_THORNSTRING,
-                 "IOBasic_WriteInfo: Internal error in reduction '%s'", 
-                 operator);
-      retval = -2;
+      reduction->value = (double) *(CCTK_INT4 *) ptr;
+    }
+#endif
+#ifdef CCTK_INT8
+    else if (vtype == CCTK_VARIABLE_INT8)
+    {
+      reduction->value = (double) *(CCTK_INT8 *) ptr;
+    }
+#endif
+#ifdef CCTK_REAL4
+    else if (vtype == CCTK_VARIABLE_REAL4)
+    {
+      reduction->value = (double) *(CCTK_REAL4 *) ptr;
+    }
+    else if (vtype == CCTK_VARIABLE_COMPLEX8)
+    {
+      reduction->value = (double) ((CCTK_REAL4 *) ptr)[0];
+      reduction->next->value = (double) ((CCTK_REAL4 *) ptr)[1];
+      reduction->next->is_valid = 1;
+    }
+#endif
+#ifdef CCTK_REAL8
+    else if (vtype == CCTK_VARIABLE_REAL8)
+    {
+      reduction->value = (double) *(CCTK_REAL8 *) ptr;
+    }
+    else if (vtype == CCTK_VARIABLE_COMPLEX16)
+    {
+      reduction->value = (double) ((CCTK_REAL8 *) ptr)[0];
+      reduction->next->value = (double) ((CCTK_REAL8 *) ptr)[1];
+      reduction->next->is_valid = 1;
+    }
+#endif
+#ifdef CCTK_REAL16
+    else if (vtype == CCTK_VARIABLE_REAL16)
+    {
+      reduction->value = (double) *(CCTK_REAL16 *) ptr;
+    }
+    else if (vtype == CCTK_VARIABLE_COMPLEX32)
+    {
+      reduction->value = (double) ((CCTK_REAL16 *) ptr)[0];
+      reduction->next->value = (double) ((CCTK_REAL16 *) ptr)[1];
+      reduction->next->is_valid = 1;
+    }
+#endif
+    else
+    {
+      CCTK_WARN (3, "IOBasic_WriteInfo: Unsupported data type");
+      reduction->is_valid = 0;
     }
   }
   else
   {
-    CCTK_VWarn(1, __LINE__, __FILE__, CCTK_THORNSTRING,
-               "IOBasic_WriteInfo: Reduction operator '%s' not found", 
-               operator);
-    retval = -1;
-  }
+    /* for CCTK_GF and CCTK_ARRAY variables: loop over all reductions */
+    while (reduction)
+    {
+      reduction->is_valid = CCTK_Reduce (GH, 0, reduction->handle, 1,
+                                         CCTK_VARIABLE_REAL,
+                                         &reduction->value, 1, vindex) == 0;
+      if (! reduction->is_valid)
+      {
+        CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
+                    "IOBasic_WriteInfo: Internal error in reduction '%s'",
+                    reduction->name);
+      }
 
-  return retval;
+      reduction = reduction->next;
+    }
+  }
 }
diff --git a/src/WriteScalar.c b/src/WriteScalar.c
new file mode 100644
index 0000000..8528bb8
--- /dev/null
+++ b/src/WriteScalar.c
@@ -0,0 +1,416 @@
+/*@@
+   @routine    WriteScalar.c
+   @date       18th September 1999
+   @author     Gabrielle Allen
+   @desc 
+               Dumps data for IOBasic's "Scalar" I/O method to output files
+   @enddesc 
+@@*/
+
+#include <ctype.h>
+#include <stdlib.h>
+#include <string.h>      /* strlen(3) */
+#include <sys/types.h>
+#include <sys/stat.h>    /* stat(2) */
+
+#include "cctk.h"
+#include "cctk_Parameters.h"
+#include "CactusBase/IOUtil/src/ioutil_AdvertisedFiles.h"
+#include "CactusBase/IOUtil/src/ioutil_CheckpointRecovery.h"
+#include "iobasicGH.h"
+
+static const char *rcsid = "$Header$";
+
+CCTK_FILEVERSION(CactusBase_IOBasic_WriteScalar_c)
+
+
+static FILE *OpenScalarFile (cGH *GH,
+                             int vindex,
+                             const char *filename,
+                             const char *slicename,
+                             const char *description,
+                             const char *aliasname);
+
+ /*@@
+   @routine   IOBasic_WriteScalarGA
+   @date      Mon Jun 19 2000
+   @author    Thomas Radke
+   @desc
+              Apply the given reduction operators on the CCTK_ARRAY or
+              CCTK_GF variable and output the result into a text file
+              suitable for postprocessing by either gluplot or xgraph.
+   @enddesc
+
+   @calls     CCTK_QueryGroupStorageI
+              CCTK_Reduce
+              CCTK_ReductionHandle
+              IOUtil_RestartFromRecovery
+              IOUtil_AdvertiseFile
+
+   @var       GH
+   @vdesc     Pointer to CCTK grid hierarchy
+   @vtype     cGH *
+   @vio       in
+   @endvar
+   @var       vindex
+   @vdesc     CCTK index of the variable to output
+   @vtype     int
+   @vio       in
+   @endvar
+   @var       alias
+   @vdesc     alias name to use for building the output filename
+   @vtype     const char *
+   @vio       in
+   @endvar
+@@*/
+void IOBasic_WriteScalarGA (cGH *GH,
+                            int vindex,
+                            const char *alias)
+{
+  DECLARE_CCTK_PARAMETERS
+  int ierr;
+  int reduction_handle;
+  iobasicGH *myGH;
+  FILE *file;
+  char *filename;
+  char *reduction_op;
+  char *string_start;
+  char *string_end;
+  char format_str[15];
+  const char *file_extension;
+  char *fullname;
+  CCTK_REAL reduction_value;
+  union
+  {
+    char *non_const_ptr;
+    const char *const_ptr;
+  } reductions;
+
+
+  /* this union helps us to avoid compiler warning about discarding
+     the const qualifier from a pointer target type */
+  reductions.const_ptr = outScalar_reductions;
+
+  /* first, check if variable has storage assigned */
+  if (! CCTK_QueryGroupStorageI (GH, CCTK_GroupIndexFromVarI (vindex)))
+  {
+    fullname = CCTK_FullName (vindex);
+    CCTK_VWarn (2, __LINE__, __FILE__, CCTK_THORNSTRING,
+                "IOBasic_WriteScalarGA: No scalar output for '%s' (no storage)", 
+                fullname);
+    free (fullname);
+    return;
+  }
+
+  /* set output format */
+  sprintf (format_str, "%%%s\t%%%s\n", out_format, out_format);
+
+  /* set the output file extension and the output style */
+  file_extension = CCTK_Equals (outScalar_style, "gnuplot") ? ".asc" : ".xg";
+
+  /* get the GH extension handle for IOBasic */
+  myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
+
+  /* allocate strings for the filename and the reduction operator */
+  filename = (char *) malloc (strlen (myGH->outdirScalar) + strlen (alias) +
+                              strlen (reductions.const_ptr) +
+                              strlen (file_extension) + 3);
+  reduction_op = (char *) malloc (strlen (reductions.const_ptr) + 1);
+
+  /* now loop over all reduction operators */
+  string_start = reductions.non_const_ptr;
+  while (string_start && *string_start)
+  {
+    /* skip leading spaces */
+    while (isspace ((int) *string_start))
+    {
+      string_start++;
+    }
+    if (! *string_start)
+    {
+      break;
+    }
+
+    /* advance to end of the operator string */
+    string_end = string_start + 1;
+    while (*string_end && ! isspace ((int) *string_end))
+    {
+      string_end++;
+    }
+
+    /* copy the operator string */
+    strncpy (reduction_op, string_start, string_end - string_start);
+    reduction_op[string_end - string_start] = 0;
+    string_start = string_end;
+
+    /* get the reduction handle from the reduction operator */
+    reduction_handle = CCTK_ReductionHandle (reduction_op);
+    if (reduction_handle < 0) 
+    {
+      CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
+                  "IOBasic_WriteScalarGA: Invalid reduction operator '%s'", 
+                  reduction_op);
+      continue;
+    }
+
+    /* do the reduction (all processors) */
+    ierr = CCTK_Reduce (GH, 0, reduction_handle, 1, CCTK_VARIABLE_REAL,
+                        &reduction_value, 1, vindex);
+
+    /* dump the reduction value to file by processor 0 */
+    if (ierr == 0 && CCTK_MyProc (GH) == 0)
+    {
+
+      /* build the filename */
+      if (new_filename_scheme)
+      {
+        sprintf (filename, "%s%s_%s%s", myGH->outdirScalar, alias,
+                                        reduction_op, file_extension);
+      }
+      else
+      {
+        /* FIXME: this check can go if we switch to the new filename scheme */
+        if (strcmp (reduction_op, "minimum") == 0)
+        {
+          file_extension = "min";
+        }
+        else if (strcmp (reduction_op, "maximum") == 0)
+        {
+          file_extension = "max";
+        }
+        else if (strcmp (reduction_op, "norm1") == 0)
+        {
+          file_extension = "nm1";
+        }
+        else if (strcmp (reduction_op, "norm2") == 0)
+        {
+          file_extension = "nm2";
+        }
+        else
+        {
+          file_extension = "unknown";
+        }
+        sprintf (filename, "%s%s_%s.tl", myGH->outdirScalar, alias,
+                 file_extension);
+      }
+
+      file = OpenScalarFile (GH, vindex, filename, reduction_op,
+                             "Reduction on Grid Arrays", alias);
+      if (file)
+      {
+        /* write the data and close the file */
+        fprintf (file, format_str, GH->cctk_time, reduction_value);
+        fclose (file);
+      }
+      else
+      {
+        CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
+                    "IOBasic_WriteScalarGA: Could not open output file '%s'", 
+                    filename);
+      }
+    }
+  }
+
+  /* free allocated resources */
+  free (reduction_op);
+  free (filename);
+}
+
+
+ /*@@
+   @routine   IOBasic_WriteScalarGS
+   @date      Mon Jun 19 2000
+   @author    Thomas Radke
+   @desc
+              Output the value of a CCTK_SCALAR variable into an ASCII file
+              suitable for postprocessing by either gluplot or xgraph.
+   @enddesc
+
+   @calls     CCTK_QueryGroupStorageI
+              CCTK_Reduce
+              CCTK_ReductionHandle
+              IOUtil_RestartFromRecovery
+              IOUtil_AdvertiseFile
+
+   @var       GH
+   @vdesc     Pointer to CCTK grid hierarchy
+   @vtype     cGH *
+   @vio       in
+   @endvar
+   @var       vindex
+   @vdesc     CCTK index of the variable to output
+   @vtype     int
+   @vio       in
+   @endvar
+   @var       alias
+   @vdesc     alias name to use for building the output filename
+   @vtype     const char *
+   @vio       in
+   @endvar
+@@*/
+void IOBasic_WriteScalarGS (cGH *GH, int vindex, const char *alias)
+{
+  DECLARE_CCTK_PARAMETERS
+  FILE *file;
+  void *data;
+  iobasicGH *myGH;
+  char *fullname, *filename;
+  char format_str_real[15], format_str_int[15];
+
+
+  /* output is done by processor 0 only */
+  if (CCTK_MyProc (GH) != 0) 
+  {
+    return;
+  }
+
+  /* first, check if variable has storage assigned */
+  if (! CCTK_QueryGroupStorageI (GH, CCTK_GroupIndexFromVarI (vindex)))
+  {
+    fullname = CCTK_FullName (vindex);
+    CCTK_VWarn (2, __LINE__, __FILE__, CCTK_THORNSTRING,
+                "IOBasic_WriteScalarGS: No scalar output for '%s' (no storage)",
+                fullname);
+    free (fullname);
+    return;
+  }
+
+  /* set the output format string for the desired notation */
+  sprintf (format_str_real, "%%%s\t%%%s\n", out_format, out_format);
+  sprintf (format_str_int,  "%%%s\t%%d\n", out_format);
+
+  /* get the GH extensions for IOBasic */
+  myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
+
+  /* build the output filename */
+  filename = (char *) malloc (strlen (myGH->outdirScalar) + strlen (alias) + 4);
+  sprintf (filename, "%s%s.tl", myGH->outdirScalar, alias);
+
+  file = OpenScalarFile (GH, vindex, filename, "tl", "Scalar value", alias);
+  if (file)
+  {
+    /* get the data pointer */
+    data = CCTK_VarDataPtrI (GH, 0, vindex); 
+
+    switch (CCTK_VarTypeI (vindex))
+    {
+      case CCTK_VARIABLE_REAL:
+        fprintf (file, format_str_real, GH->cctk_time,
+                 (double) *(CCTK_REAL *) data);
+        break;
+      case CCTK_VARIABLE_INT:
+        fprintf (file, format_str_int, GH->cctk_time,
+                 (int) *(CCTK_INT *) data);
+        break;
+      default:
+        CCTK_WARN (3, "Unsupported data type");
+        break;
+    }
+
+    /* close the output file */
+    fclose (file);
+  }
+  else
+  {
+    CCTK_VWarn (1, __LINE__, __FILE__, CCTK_THORNSTRING,
+                "IOBasic_WriteScalarGS: Could not open output file '%s'",
+                filename);
+  }
+
+  /* clean up */
+  free (filename);
+}
+
+
+static FILE *OpenScalarFile (cGH *GH,
+                             int vindex,
+                             const char *filename,
+                             const char *slicename,
+                             const char *description,
+                             const char *aliasname)
+{
+  DECLARE_CCTK_PARAMETERS
+  FILE *file;
+  char comment_char, buffer[128];
+  ioAdvertisedFileDesc advertised_file; 
+  iobasicGH *myGH;
+  char *openmode;
+  struct stat fileinfo;
+
+
+  /* get the GH extension handle for IOBasic */
+  myGH = (iobasicGH *) CCTK_GHExtension (GH, "IOBasic");
+
+  /* see if output files for this alias name were already created */
+  if (GetNamedData (myGH->filenameListScalar, filename) == NULL)
+  {
+    /* if restart from recovery, all existing files are opened
+       in append mode */
+    if (IOUtil_RestartFromRecovery (GH))
+      openmode = stat (filename, &fileinfo) == 0 ? "a" : "w";
+    else
+      openmode = "w";
+  }
+  else
+  {
+    openmode = "a";
+  }
+
+  /* open the output file with the given mode */
+  file = fopen (filename, openmode);
+  if (file && *openmode == 'w')
+  {
+    if (CCTK_Equals (outScalar_style, "gnuplot")) 
+    {
+      comment_char = '#';
+      advertised_file.mimetype = "application/gnuplot";
+    }
+    else
+    {
+      comment_char = '"';    /* this is for xgraph */
+      advertised_file.mimetype = "application/x-graph";
+    }
+
+    /* just store a non-NULL pointer in database */
+    StoreNamedData (&myGH->filenameListScalar, filename, (void *) 1);
+
+    /* advertise the file for downloading */
+    advertised_file.slice = strdup (slicename);
+    advertised_file.thorn = CCTK_THORNSTRING;
+    advertised_file.varname = CCTK_FullName (vindex);
+    advertised_file.description = strdup (description);
+
+    IOUtil_AdvertiseFile (GH, filename, &advertised_file);
+
+    /* write the file info and the header */
+    if (CCTK_Equals (out_fileinfo, "parameter filename") ||
+        CCTK_Equals (out_fileinfo, "all"))
+    {
+      buffer[0] = 0;
+      CCTK_ParameterFilename (sizeof (buffer), buffer);
+      fprintf (file, "%cParameter file %s\n", comment_char, buffer);
+    }
+    if (CCTK_Equals (out_fileinfo, "creation date") ||
+        CCTK_Equals (out_fileinfo, "all"))
+    {
+      buffer[0] = 0;
+      Util_CurrentDate (sizeof (buffer), buffer);
+      fprintf (file, "%cCreated %s ", comment_char, buffer);
+      Util_CurrentTime (sizeof (buffer), buffer);
+      fprintf (file, "%s\n", buffer);
+    }
+    if (CCTK_Equals (out_fileinfo, "axis labels") ||
+        CCTK_Equals (out_fileinfo, "all"))
+    {
+      fprintf (file, "%cx-label time\n", comment_char);
+      fprintf (file, "%cy-label %s\n", comment_char, advertised_file.varname);
+    }
+    fprintf (file, "%c%s v time\n", comment_char, aliasname);
+
+    free (advertised_file.description);
+    free (advertised_file.varname);
+    free (advertised_file.slice);
+  }
+
+  return (file);
+}
diff --git a/src/iobasicGH.h b/src/iobasicGH.h
index fe1cb16..d9c6b9a 100644
--- a/src/iobasicGH.h
+++ b/src/iobasicGH.h
@@ -1,9 +1,9 @@
  /*@@
-   @header    iobasic.h
+   @header    iobasicGH.h
    @date      Friday 18th September 1999
    @author    Gabrielle Allen
-   @desc 
-   The extensions to the GH structure from IOBasic.
+   @desc
+              The extensions to the GH structure from IOBasic.
    @enddesc
    @version $Header$
  @@*/
@@ -11,25 +11,40 @@
 #include "StoreNamedData.h"
 
 
-typedef struct IOBASICGH {
+typedef struct IOBASIC_REDUCTION
+{
+  int handle;
+  char *name;
+  char is_valid;
+  CCTK_REAL value;
+  struct IOBASIC_REDUCTION *next;
+} iobasic_reduction_t;
 
+typedef struct IOBASIC_REDUCTIONLIST
+{
+  unsigned int num_reductions;
+  iobasic_reduction_t *reductions;
+} iobasic_reductionlist_t;
+
+typedef struct IOBASIC_GH
+{
   /* how often to output */
   int  outScalar_every;
   int  outInfo_every;
+  char info_reductions_changed;
 
-  /* flags indicating output for var [i] */
-  char   *do_outInfo;
+  /* flags indicating output for variable i */
   char   *do_outScalar;
 
-  /* directory in which to output */
+  /* directory in which to place scalar output */
   char  *outdirScalar;
 
   /* The last iteration output */
   int   *outInfo_last;
   int   *outScalar_last;
 
-  /* The values for info */
-  CCTK_REAL **infovals;
+  /* The reduction lists for info output for all variables */
+  iobasic_reductionlist_t *info_reductions;
 
   /* database for names of output files that were already created */
   pNamedData *filenameListScalar;
@@ -37,7 +52,16 @@ typedef struct IOBASICGH {
 } iobasicGH;
 
 
-/* function prototypes */
-void IOBasic_Write (cGH *GH, int vindex, const char *alias);
-void IOBasic_WriteGF (cGH *GH, int vindex, const char *alias);
-int IOBasic_WriteInfo (cGH *GH, CCTK_REAL *val,int vindex, const char *operator, const char *alias);
+/* prototypes of functions to be registered */
+int IOBasic_InfoOutputGH (cGH *GH);
+int IOBasic_TriggerInfoOutput (cGH *GH, int vindex);
+int IOBasic_TimeForInfoOutput (cGH *GH, int vindex);
+int IOBasic_ScalarOutputGH (cGH *GH);
+int IOBasic_TriggerScalarOutput (cGH *GH, int vindex);
+int IOBasic_TimeForScalarOutput (cGH *GH, int vindex);
+int IOBasic_ScalarOutputVarAs (cGH *GH, const char *vname, const char *alias);
+
+/* other function prototypes */
+void IOBasic_WriteInfo (cGH *GH, int vindex);
+void IOBasic_WriteScalarGS (cGH *GH, int vindex, const char *alias);
+void IOBasic_WriteScalarGA (cGH *GH, int vindex, const char *alias);
diff --git a/src/make.code.defn b/src/make.code.defn
index bf9e62d..b28bd34 100644
--- a/src/make.code.defn
+++ b/src/make.code.defn
@@ -3,13 +3,7 @@
 
 # Source files in this directory
 SRCS = Startup.c \
-       GHExtension.c \
-       Output.c \
+       OutputScalar.c \
        OutputInfo.c \
-       Write.c \
-       WriteGF.c \
+       WriteScalar.c \
        WriteInfo.c 
-
-# Subdirectories containing source files
-SUBDIRS = 
-