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<A NAME="PetscGetCPUTime"><H1>PetscGetCPUTime</H1></A>
Returns the CPU time in seconds used by the process.
<H3><FONT COLOR="#CC3333">Synopsis</FONT></H3>
<PRE>
#include "petsc.h"
int PetscGetCPUTime(PetscLogDouble *t)
</PRE>
Not Collective
<P>
<H3><FONT COLOR="#CC3333">Output Parameter</FONT></H3>
<DT><B>t </B> -Time in seconds charged to the process.
<br>
<P>
<H3><FONT COLOR="#CC3333">Example</FONT></H3>
<PRE>
#include "petsc.h"
...
PetscLogDouble t1, t2;
ierr = <A HREF="../Sys/PetscGetCPUTime.html#PetscGetCPUTime">PetscGetCPUTime</A>(&t1);<A HREF="../Sys/CHKERRQ.html#CHKERRQ">CHKERRQ</A>(ierr);
... code to time ...
ierr = <A HREF="../Sys/PetscGetCPUTime.html#PetscGetCPUTime">PetscGetCPUTime</A>(&t2);<A HREF="../Sys/CHKERRQ.html#CHKERRQ">CHKERRQ</A>(ierr);
printf("Code took %f CPU seconds\n", t2-t1);
</PRE>
<P>
<P>
<H3><FONT COLOR="#CC3333">Notes</FONT></H3>
One should use <A HREF="../Profiling/PetscGetTime.html#PetscGetTime">PetscGetTime</A>() or the -log_summary option of
PETSc for profiling. The CPU time is NOT a realistic number to
use since it does not include the time for message passing etc.
Also on many systems the accuracy is only on the order of microseconds.
<P><B><P><B><FONT COLOR="#CC3333">Level:</FONT></B>intermediate
<BR><FONT COLOR="#CC3333">Location:</FONT></B><A HREF="../../../src/sys/src/time/cputime.c.html#PetscGetCPUTime">src/sys/src/time/cputime.c</A>
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