3.237. __nv_log2

double @__nv_log2(double %x)

Calculate the base 2 logarithm of the input argument.

Calculate the base 2 logarithm of the input argument x.

Note

For accuracy information, see the CUDA C++ Programming Guide, Mathematical Functions Appendix, Double-Precision Floating-Point Functions section.

Returns

• __nv_log2( \(\pm 0\) ) returns \(-\infty\).

• __nv_log2(1) returns +0.

• __nv_log2(x) returns NaN for x < 0.

• __nv_log2( \(+\infty\) ) returns \(+\infty\).