36 lines
381 B
C
36 lines
381 B
C
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#include "f2c.h"
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#ifdef KR_headers
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double pow_di(ap, bp) doublereal *ap; integer *bp;
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#else
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double pow_di(doublereal *ap, integer *bp)
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#endif
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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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