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/* lapack/double/dladiv.f -- translated by f2c (version 20050501).
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
*/
#ifdef __cplusplus
extern "C" {
#endif
#include "v3p_netlib.h"
/*< SUBROUTINE DLADIV( A, B, C, D, P, Q ) >*/
/* Subroutine */ int dladiv_(doublereal *a, doublereal *b, doublereal *c__,
doublereal *d__, doublereal *p, doublereal *q)
{
doublereal e, f;
/* -- LAPACK auxiliary routine (version 3.0) -- */
/* Univ. of Tennessee, Univ. of California Berkeley, NAG Ltd., */
/* Courant Institute, Argonne National Lab, and Rice University */
/* October 31, 1992 */
/* .. Scalar Arguments .. */
/*< DOUBLE PRECISION A, B, C, D, P, Q >*/
/* .. */
/* Purpose */
/* ======= */
/* DLADIV performs complex division in real arithmetic */
/* a + i*b */
/* p + i*q = --------- */
/* c + i*d */
/* The algorithm is due to Robert L. Smith and can be found */
/* in D. Knuth, The art of Computer Programming, Vol.2, p.195 */
/* Arguments */
/* ========= */
/* A (input) DOUBLE PRECISION */
/* B (input) DOUBLE PRECISION */
/* C (input) DOUBLE PRECISION */
/* D (input) DOUBLE PRECISION */
/* The scalars a, b, c, and d in the above expression. */
/* P (output) DOUBLE PRECISION */
/* Q (output) DOUBLE PRECISION */
/* The scalars p and q in the above expression. */
/* ===================================================================== */
/* .. Local Scalars .. */
/*< DOUBLE PRECISION E, F >*/
/* .. */
/* .. Intrinsic Functions .. */
/*< INTRINSIC ABS >*/
/* .. */
/* .. Executable Statements .. */
/*< IF( ABS( D ).LT.ABS( C ) ) THEN >*/
if (abs(*d__) < abs(*c__)) {
/*< E = D / C >*/
e = *d__ / *c__;
/*< F = C + D*E >*/
f = *c__ + *d__ * e;
/*< P = ( A+B*E ) / F >*/
*p = (*a + *b * e) / f;
/*< Q = ( B-A*E ) / F >*/
*q = (*b - *a * e) / f;
/*< ELSE >*/
} else {
/*< E = C / D >*/
e = *c__ / *d__;
/*< F = D + C*E >*/
f = *d__ + *c__ * e;
/*< P = ( B+A*E ) / F >*/
*p = (*b + *a * e) / f;
/*< Q = ( -A+B*E ) / F >*/
*q = (-(*a) + *b * e) / f;
/*< END IF >*/
}
/*< RETURN >*/
return 0;
/* End of DLADIV */
/*< END >*/
} /* dladiv_ */
#ifdef __cplusplus
}
#endif
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