48 строки
1.1 KiB
Groff
48 строки
1.1 KiB
Groff
.\"Copyright 2006, Sun Microsystems, Inc.
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.\" Copyright (c) 1996 Thinking Machines Corporation
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.TH MPI_Wtick 3OpenMPI "September 2006" "Open MPI 1.2" " "
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.SH NAME
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\fBMPI_Wtick\fP \- Returns the resolution of MPI_Wtime.
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.SH SYNTAX
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.ft R
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.SH C Syntax
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.nf
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#include <mpi.h>
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double MPI_Wtick()
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.SH Fortran Syntax
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.nf
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INCLUDE 'mpif.h'
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DOUBLE PRECISION MPI_WTICK()
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.SH C++ Syntax
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.nf
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#include <mpi.h>
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double MPI::Wtick()
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.SH RETURN VALUE
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.ft R
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Time in seconds of resolution of MPI_Wtime.
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.SH DESCRIPTION
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.ft R
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MPI_Wtick returns the resolution of MPI_Wtime in seconds. That is, it
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returns, as a double-precision value, the number of seconds between
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successive clock ticks. For example, if the clock is implemented by
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the hardware as a counter that is incremented every millisecond, the
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value returned by MPI_Wtick should be 10^-3.
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.PP
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Note that on POSIX platforms, Open MPI should always return 10^-6 for
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MPI_Wtick. The returned value may be different on Windows platforms.
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.PP
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.SH NOTE
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This function does not return an error value. Consequently, the result
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of calling it before MPI_Init or after MPI_Finalize is undefined.
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.SH SEE ALSO
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.ft R
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.sp
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MPI_Wtime
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