28 lines
428 B
C
28 lines
428 B
C
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/* Portable fmod(x, y) implementation for systems that don't have it */
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#include <math.h>
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#include <errno.h>
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extern int errno;
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double
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fmod(x, y)
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double x, y;
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{
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double i, f;
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if (y == 0.0) {
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errno = EDOM;
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return 0.0;
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}
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/* return f such that x = i*y + f for some integer i
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such that |f| < |y| and f has the same sign as x */
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i = floor(x/y);
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f = x - i*y;
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if ((x < 0.0) != (y < 0.0))
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f = f-y;
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return f;
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}
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