MPI_WTIME, MPI_Wtime

Purpose

Returns the current value of time as a floating-point value.

C synopsis

#include <mpi.h>
double MPI_Wtime(void);

C++ synopsis

#include mpi.h
double MPI::Wtime();

FORTRAN synopsis

include 'mpif.h' or use mpi
DOUBLE PRECISION MPI_WTIME()

Parameters

None.

Description

This subroutine returns the current value of time as a double precision
floating point number of seconds. This value represents elapsed time since
some point in the past. This time in the past will not change during the
life of the task. You are responsible for converting the number of seconds
into other units if you prefer.

Notes

You can use the attribute key MPI_WTIME_IS_GLOBAL to determine if the
values returned by MPI_WTIME on different nodes are synchronized. See
MPI_ATTR_GET for more information.

The environment variable MP_CLOCK_SOURCE lets you control where MPI_WTIME
gets its time values from. See IBM Parallel Environment for AIX: MPI
Programming Guide for more information.

Errors

MPI not initialized

MPI already finalized

Related information

     MPI_ATTR_GET