WSJT-X/igray.c
Joe Taylor fc6221043a Made importing of numpy/Numeric more flexible, as in WSJT.
Changed compile-time flag Win32 to CVF (for Compaq Visual Fortran).


git-svn-id: svn+ssh://svn.code.sf.net/p/wsjt/wsjt/branches/map65@618 ab8295b8-cf94-4d9e-aec4-7959e3be5d79
2007-12-31 15:15:55 +00:00

23 lines
315 B
C

#ifdef CVF
extern int __stdcall IGRAY(int *n0, int *idir)
#else
int igray_(int *n0, int *idir)
#endif
{
int n;
unsigned long sh;
unsigned long nn;
n=*n0;
if(*idir>0) return (n ^ (n >> 1));
sh = 1;
nn = (n >> sh);
while (nn > 0) {
n ^= nn;
sh <<= 1;
nn = (n >> sh);
}
return (n);
}