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gcc/libf2c/libF77/z_div.c
Toon Moene 6973bf5482 configure.in: Define IEEE_COMPLEX_DIVIDE.
* libF77/configure.in: Define IEEE_COMPLEX_DIVIDE.
	* libF77/[cz]_div.c: Arrange for compilation under
	-DIEEE_COMPLEX_DIVIDE to make these routines
	avoid calling sig_die when the denominator vanishes.
	* libF77/s_rnge.c: Add casts for the case of
	sizeof(ftnint) == sizeof(int) < sizeof(long).
	* libI77/endfile.c: Set state to writing (b->uwrt = 1) when an
	endfile statement requires copying the file
	Also, supply a missing (long) cast in the sprintf call.
	* libI77/sfe.c: Add #ifdef ALWAYS_FLUSH logic, for formatted I/O.

From-SVN: r32496
2000-03-12 19:20:47 +00:00

45 lines
840 B
C

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