33 lines
347 B
C
33 lines
347 B
C
#include "f2c.h"
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double
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pow_di (doublereal * ap, integer * bp)
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{
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double pow, x;
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integer n;
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unsigned long u;
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pow = 1;
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x = *ap;
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n = *bp;
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if (n != 0)
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{
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if (n < 0)
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{
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n = -n;
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x = 1 / x;
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}
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for (u = n;;)
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{
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if (u & 01)
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pow *= x;
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if (u >>= 1)
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x *= x;
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else
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break;
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}
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}
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return (pow);
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}
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