/* -- translated by f2c (version 20191129). You must link the resulting object file with libf2c: on Microsoft Windows system, link with libf2c.lib; on Linux or Unix systems, link with .../path/to/libf2c.a -lm or, if you install libf2c.a in a standard place, with -lf2c -lm -- in that order, at the end of the command line, as in cc *.o -lf2c -lm Source for libf2c is in /netlib/f2c/libf2c.zip, e.g., http://www.netlib.org/f2c/libf2c.zip */ #include "f2c.h" /* > \brief \b IDAMAX =========== DOCUMENTATION =========== Online html documentation available at http://www.netlib.org/lapack/explore-html/ Definition: =========== INTEGER FUNCTION IDAMAX(N,DX,INCX) INTEGER INCX,N DOUBLE PRECISION DX(*) > \par Purpose: ============= > > \verbatim > > IDAMAX finds the index of the first element having maximum absolute value. > \endverbatim Arguments: ========== > \param[in] N > \verbatim > N is INTEGER > number of elements in input vector(s) > \endverbatim > > \param[in] DX > \verbatim > DX is DOUBLE PRECISION array, dimension ( 1 + ( N - 1 )*abs( INCX ) ) > \endverbatim > > \param[in] INCX > \verbatim > INCX is INTEGER > storage spacing between elements of SX > \endverbatim Authors: ======== > \author Univ. of Tennessee > \author Univ. of California Berkeley > \author Univ. of Colorado Denver > \author NAG Ltd. > \date November 2017 > \ingroup aux_blas > \par Further Details: ===================== > > \verbatim > > jack dongarra, linpack, 3/11/78. > modified 3/93 to return if incx .le. 0. > modified 12/3/93, array(1) declarations changed to array(*) > \endverbatim > ===================================================================== */ integer igraphidamax_(integer *n, doublereal *dx, integer *incx) { /* System generated locals */ integer ret_val, i__1; doublereal d__1; /* Local variables */ integer i__, ix; doublereal dmax__; /* -- Reference BLAS level1 routine (version 3.8.0) -- -- Reference BLAS is a software package provided by Univ. of Tennessee, -- -- Univ. of California Berkeley, Univ. of Colorado Denver and NAG Ltd..-- November 2017 ===================================================================== Parameter adjustments */ --dx; /* Function Body */ ret_val = 0; if (*n < 1 || *incx <= 0) { return ret_val; } ret_val = 1; if (*n == 1) { return ret_val; } if (*incx == 1) { /* code for increment equal to 1 */ dmax__ = abs(dx[1]); i__1 = *n; for (i__ = 2; i__ <= i__1; ++i__) { if ((d__1 = dx[i__], abs(d__1)) > dmax__) { ret_val = i__; dmax__ = (d__1 = dx[i__], abs(d__1)); } } } else { /* code for increment not equal to 1 */ ix = 1; dmax__ = abs(dx[1]); ix += *incx; i__1 = *n; for (i__ = 2; i__ <= i__1; ++i__) { if ((d__1 = dx[ix], abs(d__1)) > dmax__) { ret_val = i__; dmax__ = (d__1 = dx[ix], abs(d__1)); } ix += *incx; } } return ret_val; } /* igraphidamax_ */