40 lines
939 B
C++
40 lines
939 B
C++
#ifdef __cplusplus
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extern "C" {
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#endif
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#include "lmp_f2c.h"
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doublereal dlapy2_(doublereal *x, doublereal *y)
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{
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doublereal ret_val, d__1;
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double sqrt(doublereal);
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logical x_is_nan__, y_is_nan__;
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doublereal w, z__, xabs, yabs;
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extern doublereal dlamch_(char *, ftnlen);
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extern logical disnan_(doublereal *);
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doublereal hugeval;
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x_is_nan__ = disnan_(x);
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y_is_nan__ = disnan_(y);
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if (x_is_nan__) {
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ret_val = *x;
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}
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if (y_is_nan__) {
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ret_val = *y;
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}
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hugeval = dlamch_((char *)"Overflow", (ftnlen)8);
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if (!(x_is_nan__ || y_is_nan__)) {
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xabs = abs(*x);
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yabs = abs(*y);
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w = max(xabs, yabs);
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z__ = min(xabs, yabs);
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if (z__ == 0. || w > hugeval) {
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ret_val = w;
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} else {
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d__1 = z__ / w;
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ret_val = w * sqrt(d__1 * d__1 + 1.);
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}
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}
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return ret_val;
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}
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#ifdef __cplusplus
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}
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#endif
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