56 lines
959 B
C
Executable File
56 lines
959 B
C
Executable File
/* csqrtl.c */
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/*
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Contributed by Danny Smith
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2005-01-04
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*/
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#include <math.h>
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#include <complex.h>
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long double complex csqrtl (long double complex Z)
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{
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long double complex Res;
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long double r;
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long double x = __real__ Z;
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long double y = __imag__ Z;
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if (y == 0.0L)
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{
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if (x < 0.0L)
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{
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__real__ Res = 0.0L;
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__imag__ Res = sqrtl (-x);
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}
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else
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{
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__real__ Res = sqrtl (x);
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__imag__ Res = 0.0L;
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}
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}
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else if (x == 0.0L)
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{
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r = sqrtl(0.5L * fabsl (y));
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__real__ Res = y > 0 ? r : -r;
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__imag__ Res = r;
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}
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else
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{
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long double t = sqrtl (2.0L * (hypotl (__real__ Z, __imag__ Z) + fabsl (x)));
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long double u = t / 2.0L;
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if ( x > 0.0L)
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{
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__real__ Res = u;
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__imag__ Res = y / t;
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}
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else
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{
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__real__ Res = fabsl (y / t);
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__imag__ Res = y < 0 ? -u : u;
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}
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}
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return Res;
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}
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