V7/usr/src/libF77/z_exp.c

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#include "complex"

z_exp(r, z)
dcomplex *r, *z;
{
double expx;
double exp(), cos(), sin();

expx = exp(z->dreal);
r->dreal = expx * cos(z->dimag);
r->dimag = expx * sin(z->dimag);
}