61 lines
1.2 KiB
C
61 lines
1.2 KiB
C
#include "clapack.h"
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doublereal slapy2_(real *x, real *y)
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{
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/* System generated locals */
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real ret_val, r__1;
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/* Builtin functions */
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double sqrt(doublereal);
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/* Local variables */
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real w, z__, xabs, yabs;
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/* -- LAPACK auxiliary routine (version 3.1) -- */
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/* Univ. of Tennessee, Univ. of California Berkeley and NAG Ltd.. */
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/* November 2006 */
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/* .. Scalar Arguments .. */
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/* .. */
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/* Purpose */
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/* ======= */
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/* SLAPY2 returns sqrt(x**2+y**2), taking care not to cause unnecessary */
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/* overflow. */
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/* Arguments */
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/* ========= */
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/* X (input) REAL */
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/* Y (input) REAL */
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/* X and Y specify the values x and y. */
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/* ===================================================================== */
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/* .. Parameters .. */
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/* .. */
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/* .. Local Scalars .. */
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/* .. */
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/* .. Intrinsic Functions .. */
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/* .. */
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/* .. Executable Statements .. */
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xabs = dabs(*x);
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yabs = dabs(*y);
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w = dmax(xabs,yabs);
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z__ = dmin(xabs,yabs);
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if (z__ == 0.f) {
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ret_val = w;
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} else {
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/* Computing 2nd power */
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r__1 = z__ / w;
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ret_val = w * sqrt(r__1 * r__1 + 1.f);
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}
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return ret_val;
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/* End of SLAPY2 */
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} /* slapy2_ */
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