3.223. __nv_log2

Prototype:

double @__nv_log2(double %x) 

Description:

Calculate the base 2 logarithm of the input argument x.

Returns:

  • __nv_log2( ± 0 ) returns .

  • __nv_log2(1) returns +0.

  • __nv_log2(x) returns NaN for x < 0.

  • __nv_log2( + ) returns + .

Note:

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

Library Availability:

Compute 2.0: Yes

Compute 3.0: Yes

Compute 3.5: Yes