diff options
Diffstat (limited to 'gnu/egcs/libf2c/libF77/c_div.c')
-rw-r--r-- | gnu/egcs/libf2c/libF77/c_div.c | 37 |
1 files changed, 37 insertions, 0 deletions
diff --git a/gnu/egcs/libf2c/libF77/c_div.c b/gnu/egcs/libf2c/libF77/c_div.c new file mode 100644 index 00000000000..ac963079ba2 --- /dev/null +++ b/gnu/egcs/libf2c/libF77/c_div.c @@ -0,0 +1,37 @@ +#include "f2c.h" + +#ifdef KR_headers +extern VOID sig_die(); +VOID c_div(c, a, b) +complex *a, *b, *c; +#else +extern void sig_die(char*,int); +void c_div(complex *c, complex *a, complex *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) + sig_die("complex division by zero", 1); + ratio = (double)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 = (double)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; + } |