signbit

Applicability

Product	Supported
Atlas 350 Accelerator Card	√
Atlas A3 training product/Atlas A3 inference product	x
Atlas A2 training product/Atlas A2 inference product	x
Atlas 200I/500 A2 inference product	x
Atlas inference product AI Core	x
Atlas inference product Vector Core	x
Atlas training product	x

Function Usage

Obtains the sign bit of the input data.

Prototype

inline int signbit(float x)

Parameters

**Table 1** Parameters
Parameter	Input/Output	Description
x	Input	Source operand.

Returns

The sign bit of the input data.

If x is nan, the return value is 0.
If x is inf, the return value is 0.
If x is -inf, the return value is 1.

Restrictions

For SIMT programming, this API is not supported.

Header File to Be Included

To use this API, the simt_api/math_functions.h header file must be included.

#include "simt_api/math_functions.h"

Examples

For SIMD and SIMT programming:

__simt_vf__ __launch_bounds__(1024) inline void KernelSignbit(__gm__ int* dst, __gm__ float* x)
{
    int idx = threadIdx.x + blockIdx.x * blockDim.x;
    dst[idx] = signbit(x[idx]); 
}

Parent topic: Mathematical Functions