On Thursday, 15 March 2018 at 16:31:56 UTC, Stefan Koch wrote:
On Thursday, 15 March 2018 at 15:28:16 UTC, Miguel L wrote:
Why does std.math.signbit only work for floating point types?
Is there an analogue function for integer types? what is the
best way to compare the sign of a float with the sign of an
integer?
Thanks in advance
integers don't have a sign-bit.
since they are not necessarily singed.
However if an integer is signed and using 1-complement
you can either do sign = var < 0 or
sign = (var & (1 << (sizeof(var)*8 - 1));
though I cannot tell which one is faster you have to experiment.
Thanks. Just one more question:
Is this code correct? I don't care about +0 or -0 as the
calculations on f guarantee it cannot be 0 at all.
int a;
float f;
....
if((a<0)==signbit(f)) {....}
else {...}
