42 lines
809 B
C
42 lines
809 B
C
#include "f2c.h"
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extern void sig_die (char *, int);
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void
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z_div (doublecomplex * c, doublecomplex * a, doublecomplex * b)
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{
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double ratio, den;
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double abr, abi, cr;
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if ((abr = b->r) < 0.)
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abr = -abr;
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if ((abi = b->i) < 0.)
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abi = -abi;
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if (abr <= abi)
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{
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if (abi == 0)
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{
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#ifdef IEEE_COMPLEX_DIVIDE
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if (a->i != 0 || a->r != 0)
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abi = 1.;
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c->i = c->r = abi / abr;
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return;
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#else
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sig_die ("complex division by zero", 1);
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#endif
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}
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ratio = b->r / b->i;
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den = b->i * (1 + ratio * ratio);
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cr = (a->r * ratio + a->i) / den;
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c->i = (a->i * ratio - a->r) / den;
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}
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else
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{
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ratio = b->i / b->r;
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den = b->r * (1 + ratio * ratio);
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cr = (a->r + a->i * ratio) / den;
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c->i = (a->i - a->r * ratio) / den;
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}
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c->r = cr;
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}
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