fix a nasty bug where, if the interpolation coordinate was close to

a grid boundary, the actual interpolation was sometimes done as if
the interpolation coordinate was displaced by one grid spacing :( :(

also add more debugging code (introduced to help track down this bug,
but there's no harm in leaving it in for possible future use)

also add explicit checks for a couple of error cases:
* interpolation coordinate is not a finite number (eg NaN or infinity)
* grid origin/delta not a finite number (eg NaN or infinity)
* grid spacing is 0 (we need to divide by this!)

also add explicit note about the test driver in this directory


git-svn-id: http://svn.aei.mpg.de/numrel/AEIThorns/AEILocalInterp/trunk@35 0f49ee68-0e4f-0410-9b9c-b2c123ded7ef

1 files changed, 4 insertions, 1 deletions

diff --git a/src/InterpLocalUniform.h b/src/InterpLocalUniform.h
index a111f02..bb412d0 100644
--- a/src/InterpLocalUniform.h
+++ b/src/InterpLocalUniform.h
@@ -35,7 +35,7 @@ typedef int bool;
 /* round floating-point value to nearest integer */
 /* ... result is expressed as floating point! */
 /* ... needs <math.h> for floor() */
-#define JT_ROUND(x)	floor((x) + 0.5)
+#define ROUND_TO_INTEGER__RESULT_IS_FP(x)	floor((x) + 0.5)
 
 /******************************************************************************/
 
@@ -175,6 +175,9 @@ struct	Jacobian_info
 /* grid is smaller than molecule */
 #define MOLECULE_POSN_ERROR_GRID_TINY	(-3)
 
+/* someone passed us a NaN or other non-finite floating-point number */
+#define MOLECULE_POSN_ERROR_NAN		(-4)
+
 /******************************************************************************/
 
 /*