39 lines
949 B
C
39 lines
949 B
C
/*BHEADER**********************************************************************
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* (c) 1997 The Regents of the University of California
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*
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* See the file COPYRIGHT_and_DISCLAIMER for a complete copyright
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* notice, contact person, and disclaimer.
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*
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* $Revision$
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*********************************************************************EHEADER*/
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/******************************************************************************
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*
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*
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*****************************************************************************/
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#include "headers.h"
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/*--------------------------------------------------------------------------
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* hypre_Log2:
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* This routine returns the integer, floor(log_2(p)).
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* If p <= 0, it returns a -1.
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*--------------------------------------------------------------------------*/
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int
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hypre_Log2(int p)
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{
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int e;
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if (p <= 0)
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return -1;
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e = 0;
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while (p > 1)
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{
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e += 1;
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p /= 2;
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}
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return e;
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}
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