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<TITLE>HPL_idamax HPL 2.0 Library Functions September 10, 2008</TITLE> |
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ALINK = "#ffff00"> |
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<H1>Name</H1> |
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<B>HPL_idamax</B> 1st k s.t. |x_k| = max_i(|x_i|). |
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<H1>Synopsis</H1> |
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<CODE>#include "hpl.h"</CODE><BR><BR> |
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<CODE>int</CODE> |
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<CODE>HPL_idamax(</CODE> |
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<CODE>const int</CODE> |
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<CODE>N</CODE>, |
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<CODE>const double *</CODE> |
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<CODE>X</CODE>, |
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<CODE>const int</CODE> |
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<CODE>INCX</CODE> |
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<CODE>);</CODE> |
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<H1>Description</H1> |
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<B>HPL_idamax</B> |
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returns the index in an n-vector x of the first element |
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having maximum absolute value. |
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<H1>Arguments</H1> |
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<PRE>
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N (local input) const int |
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On entry, N specifies the length of the vector x. N must be |
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at least zero. |
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</PRE>
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<PRE>
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X (local input) const double * |
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On entry, X is an incremented array of dimension at least |
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( 1 + ( n - 1 ) * abs( INCX ) ) that contains the vector x. |
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</PRE>
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<PRE>
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INCX (local input) const int |
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On entry, INCX specifies the increment for the elements of X. |
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INCX must not be zero. |
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<H1>Example</H1> |
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<CODE>#include "hpl.h"</CODE><BR><BR> |
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<PRE>
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int main(int argc, char *argv[]) |
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{
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double x[3]; |
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int imax; |
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x[0] = 1.0; x[1] = 3.0; x[2] = 2.0; |
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imax = HPL_idamax( 3, x, 1 ); |
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printf("imax=%d\n", imax);
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exit(0); |
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return(0); |
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} |
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</PRE>
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<H1>See Also</H1> |
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<A HREF="HPL_daxpy.html">HPL_daxpy</A>, |
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<A HREF="HPL_dcopy.html">HPL_dcopy</A>, |
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<A HREF="HPL_dscal.html">HPL_dscal</A>, |
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<A HREF="HPL_dswap.html">HPL_dswap</A>. |
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