Has anyone else tried to use the arc tangent function in SMSQ or
in C68? As far as I can see, its marginal behaviour is
incorrect. If I enter 'print atan(1,0),atan(0,1)' to SBasic, I
expect to get PI/2,0 NOT 0,0. Similar misbehaviour is shown by
atan2 in C68 (I suppose this is only a wrapper for the
underlying SMSQ module).
Shouldn't atan2 be:
double atan2(double y,double x)
{
if (x==0)
{
if (y>0) return pi/2;
else if (y<0) return -PI/2;
else return 0; /* or an OS error */
}
else return atan(y/x);
}
I know this may seem obscure but try working with angles with a
defective atan(2) function!
Christopher Cave
