21 lines
335 B
C
21 lines
335 B
C
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#include <math.h>
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double snrm(unsigned long n, double sx[], int itol)
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{
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unsigned long i,isamax;
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double ans;
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if (itol <= 3) {
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ans = 0.0;
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for (i=1;i<=n;i++) ans += sx[i]*sx[i];
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return sqrt(ans);
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} else {
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isamax=1;
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for (i=1;i<=n;i++) {
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if (fabs(sx[i]) > fabs(sx[isamax])) isamax=i;
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}
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return fabs(sx[isamax]);
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}
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}
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