mpid_wtime_acc.tex

刚才是说明 现在是安装程序在 LINUX环境下进行编程的MPICH安装文件

\startmanpage
\mantitle{MPID{\tt \char`\_}Wtime{\tt \char`\_}acc}{tex}{10/7/2002}
\manname{MPID{\tt \char`\_}Wtime{\tt \char`\_}acc}
--- Accumulate time values 
\subhead{Synopsis}
\startvb\begin{verbatim}
void MPID_Wtime_acc( MPID_Time_t t1, MPID_Time_t t2, MPID_Time_t *t3 )

\end{verbatim}
\endvb

\subhead{Input Parameters}
\startarg{t1,t2,t3 }{Three time values.  {\tt t3} is updated with the difference between 
{\tt t2} and {\tt t1}: {\tt *t3 +$=$ (t2 - t1)}.
}
\par
\subhead{Notes}
This routine is used to accumulate the time spent with a block of code
without first converting the time stamps into a particular arithmetic
type such as a {\tt double}.  For example, if the {\tt MPID{\tt \char`\_}Wtime} routine accesses
a cycle counter, this routine (or macro) can perform the accumulation using
integer arithmetic.
\par
To convert a time value accumulated with this routine, use {\tt MPID{\tt \char`\_}Wtime{\tt \char`\_}diff
}with a {\tt t1} of zero.
\par
\subhead{Module}
Timer
\endmanpage