35 lines
909 B
C++
35 lines
909 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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int dlassq_(integer *n, doublereal *x, integer *incx, doublereal *scale, doublereal *sumsq)
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{
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integer i__1, i__2;
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doublereal d__1;
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integer ix;
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doublereal absxi;
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extern logical disnan_(doublereal *);
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--x;
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if (*n > 0) {
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i__1 = (*n - 1) * *incx + 1;
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i__2 = *incx;
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for (ix = 1; i__2 < 0 ? ix >= i__1 : ix <= i__1; ix += i__2) {
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absxi = (d__1 = x[ix], abs(d__1));
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if (absxi > 0. || disnan_(&absxi)) {
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if (*scale < absxi) {
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d__1 = *scale / absxi;
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*sumsq = *sumsq * (d__1 * d__1) + 1;
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*scale = absxi;
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} else {
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d__1 = absxi / *scale;
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*sumsq += d__1 * d__1;
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}
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}
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}
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}
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return 0;
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}
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#ifdef __cplusplus
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}
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#endif
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