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diff --git a/doc/html/AMRfileReader.html b/doc/html/AMRfileReader.html new file mode 100644 index 0000000..21749b3 --- /dev/null +++ b/doc/html/AMRfileReader.html @@ -0,0 +1,157 @@ +<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN"> +<html> + <head> + <title>AmrFileReader</title> + </head> + + <body bgcolor="#F0F0F0"> + <font face="arial,helvetica"> <h1>AmrFileReader</h1></font> + + The <a href="AmrGridReader">AmrGridReader</a> only provides + unfiltered access to the grids stored in the AMR datafile. For a + real visualization application, it is necessary to filter through + these grids to present only what is relevant for a particular + domain and timestep. The <b>AmrFileReader</b> provides that sort + of filtering capability.<p> + The <b>AmrFileReader</b> selects all grids that are active at a + particular timestep in the evolution sequence. It also allows + you to mask out sets of levels (for example only show levels 1-3 + of a 7 level hierarchy). Since the stepping of grids proceeds + at different paces at different levels, the timestep is a global + quantity that refers to the finest granularity of stepping that + can occur during the evolution (the integer timesteps of the + deepest level of refinement). The API is intelligent enough to + only reload data from grids that have changed when a different + timestep has been selected since deeper-level grids will change + more rapidly than their parent grids.<p> + <hr> + <font face="arial,helvetica" color="#555588"><h2>The API</h2></font> + <UL> + <LI><a href="#CPP">C++ Interface</a> + <LI><a href="#C">C Interface</a> + <LI><a href="#F77">F77/F90 Interface</a> + </UL> + <hr> + <u><h2><a name="CPP">C++ Interface</a></h2></u> + <DL> + <DT><font color="#888888"><b>Constructors/Destructors</b></font> + <DL> + <DT><b>AmrFileReader::AmrFileReader(IObase + &filehandle)</b> <i>constructor</i> + <DD>The <i>filehandle</i> is an already + <a href="UsingC++.html#Opening">open IEEEIO or HDFIO + file</a>. This initializes the reader and attaches it to that + datafile. + <DT><b>AmrFileReader::~AmrFileReader()</b> <i>destructor</i> + <DD>This flushes all of the necessary file buffers. + The filehandle that the reader was bound to must be + closed separately though. + </DL> + <DT><font color="#888888"><b>Queries about File Contents</b></font> + <DL> + <DT><b>int AmrFileReader::nLevels()</b> + <DD>Returns the number of levels in the AMR hierarchy. This is + the deepest the hierarchy gets in this particular datafile as + opposed to the number of levels present at this time in the + evolution (this distinction is important for adaptive depth + schemes where the number of levels will change depending on + the demands of the solver). + <DT><b>AmrFileReader::getTimeRange(int &mintime,int &maxtime)</b> + <DD>Gets the range of integer timesteps stored in the file. + The nonzero mintime exists to support schemes where the + evolution is broken up among several files. + </DL> + <DT><font color="#888888"><b>Filters</b></font> + <DT>The <i><b>filter</b></i> methods listed below select grids based on + the criteria of time and level number. Grids selected by the + filter are referred to as <i><b>active grids</b></i>.<p> + <DL> + <DT><b>AmrFileReader::setTime(int time)</b> + <DD>Sets the current timestep to select the data hierarchy for. + The timestep is defined with respect to the rate at which + grids change at the deepest level of the AMR hierarchy stored + in the file. Selecting a particular timestep selects a + snapshot of the hieararchy at a particular time in the + evolution. + <DT><b>AmrFileReader::hideLevel(int level)</b> + <DD>By default all levels are visible and are read in when the + <code>getGrids()</code> method is called. You can hide + individual levels using this method. This is useful when + loading the entire hierarchy is either too confusing, too slow, or too + large for the workstation to handle. + <DT><b>AmrFileReader::showLevel(int level)</b> + <DD>Shows a level that has otherwise been hidden. + <DT><b>AmrFileReader::showAllLevels()</b> + <DD>A convenience method for making all of the levels visible. + </DL> + <DT><font color="#888888"><b>Getting the Data</b></font> + <DL> + <DT><b>int AmrFileReader::getGrids(FlexArray<AmrGrid> &g)</b> + <DD>Gets all currently active grids and puts them into a + FlexArray of + <a href="AmrGrid.html">AmrGrid</a> datastructures. An + <i>active grid</i> is one that is currently selected by the + <code>setTime()</code> and <code>show/hideLevel()</code> filters. The + FlexArray is a simple template class for arrays that grow + automatically to accomodate new elements. If you or your + compiler do not like templates, then you can use the two-step + static allocation method + (<code>getNumGrids()</code>/<code>getGrids()</code>) defined + below. + This method returns the number of active grids. + <DT><b>int AmrFileReader::getNumGrids()</b> + <DD>Returns the total number of active grids currently selected + by the <code>setTime()</code> and + <code>show/hideLevel()</code> + filters. This is used to determine how + large of an array of AmrGrid structures to allocate in order + to receive the data using the <code>getGrids()</code> method + call since this array length is static. + <DD><b>int AmrFileReader::getGrids(AmrGrid *grids)</b> + <DD>This method reads the grid information and data for all + currently active grids into the pre-allocated array of + <code>grids</code> passed to it. The API will allocate memory + for the grids upon reading the data, but it is the responsibility of + the programmer to dispose of the array of grids and the data + stored within these datastructures once they are done with it. + </DL> + <DT><font color="#888888"><b>Utility and Debugging Methods</b></font> + <DT><DL> + <DT><b>AmrFileReader::setDataLoadingOff()</b> + <DD>This causes the <code>getGrids()</code> methods + to read in the informational part of + the AmrGrid datastructures, but not load any data. This is + useful for just aquiring bounding box information or + estimating the memory/computational requirements for loading + the entire hierarchy. + <DT><b>AmrFileReader::setDataLoadingOn()</b> + <DD>This causes the <code>getGrids()</code> methods + to read both the informational and data part of + the AmrGrid datastructures. This is the default state for + this API. + <DT><b>printGridInfo()</b> + <DD>Prints information about all grids in file to STDERR. Used + only for debugging. + <DT><b>printActiveGrids()</b> + <DD>Prints information about all <b>active</b> grids to STDERR. + Used only for debugging. + <DT><b>int debug</b> + This is a public variable that can be set to a nonzero value + in order to print additional debugging information for each + method call. This printing is turned off when it is set to zero. + </DL> + </DL> + <hr> + <h2><u><a name="C">C Interface</a></u></h2> + Not ready yet. + <hr> + <h2><u><a name="F77">F77/F90 Interface</a></u></h2> + Not ready yet. + <hr> + <address><a href="mailto:jshalf@ariel.ncsa.uiuc.edu"></a></address> +<!-- Created: Thu Feb 4 10:03:12 CST 1999 --> +<!-- hhmts start --> +Last modified: Thu Feb 4 17:49:33 CST 1999 +<!-- hhmts end --> + </body> +</html> |