44 lines
846 B
C
44 lines
846 B
C
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/* cpowf.c */
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/*
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Contributed by Danny Smith
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2004-12-24
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*/
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/* cpow(X, Y) = cexp(X * clog(Y)) */
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#include <math.h>
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#include <complex.h>
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float complex cpowf (float complex X, float complex Y)
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{
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float complex Res;
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float i;
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float r = _hypot (__real__ X, __imag__ X);
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if (r == 0.0f)
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{
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__real__ Res = __imag__ Res = 0.0;
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}
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else
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{
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float rho;
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float theta;
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i = cargf (X);
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theta = i * __real__ Y;
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if (__imag__ Y == 0.0f)
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/* This gives slightly more accurate results in these cases. */
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rho = powf (r, __real__ Y);
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else
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{
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r = logf (r);
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/* rearrangement of cexp(X * clog(Y)) */
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theta += r * __imag__ Y;
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rho = expf (r * __real__ Y - i * __imag__ Y);
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}
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__real__ Res = rho * cosf (theta);
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__imag__ Res = rho * sinf (theta);
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}
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return Res;
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}
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