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/* lapack/single/slapy2.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"
/*< REAL FUNCTION SLAPY2( X, Y ) >*/
doublereal slapy2_(real *x, real *y)
{
/* System generated locals */
real ret_val, r__1;
/* Builtin functions */
double sqrt(doublereal);
/* Local variables */
real w, z__, xabs, yabs;
/* -- 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 .. */
/*< REAL X, Y >*/
/* .. */
/* Purpose */
/* ======= */
/* SLAPY2 returns sqrt(x**2+y**2), taking care not to cause unnecessary */
/* overflow. */
/* Arguments */
/* ========= */
/* X (input) REAL */
/* Y (input) REAL */
/* X and Y specify the values x and y. */
/* ===================================================================== */
/* .. Parameters .. */
/*< REAL ZERO >*/
/*< PARAMETER ( ZERO = 0.0E0 ) >*/
/*< REAL ONE >*/
/*< PARAMETER ( ONE = 1.0E0 ) >*/
/* .. */
/* .. Local Scalars .. */
/*< REAL W, XABS, YABS, Z >*/
/* .. */
/* .. Intrinsic Functions .. */
/*< INTRINSIC ABS, MAX, MIN, SQRT >*/
/* .. */
/* .. Executable Statements .. */
/*< XABS = ABS( X ) >*/
xabs = dabs(*x);
/*< YABS = ABS( Y ) >*/
yabs = dabs(*y);
/*< W = MAX( XABS, YABS ) >*/
w = dmax(xabs,yabs);
/*< Z = MIN( XABS, YABS ) >*/
z__ = dmin(xabs,yabs);
/*< IF( Z.EQ.ZERO ) THEN >*/
if (z__ == (float)0.) {
/*< SLAPY2 = W >*/
ret_val = w;
/*< ELSE >*/
} else {
/*< SLAPY2 = W*SQRT( ONE+( Z / W )**2 ) >*/
/* Computing 2nd power */
r__1 = z__ / w;
ret_val = w * sqrt(r__1 * r__1 + (float)1.);
/*< END IF >*/
}
/*< RETURN >*/
return ret_val;
/* End of SLAPY2 */
/*< END >*/
} /* slapy2_ */
#ifdef __cplusplus
}
#endif
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