modff

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

Decomposes the input data into the fractional part and the integer part.

Prototype

1
inline float modff(float x, float *n)

Parameters

Table 1 Parameters

Parameter

Input/Output

Description

x

Input

Source operand.

n

Output

Unified Buffer, Global Memory, or stack address, which is used to store the integer part of the input data.

Returns

Fractional part of the input data.

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

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.

1
#include "simt_api/math_functions.h"

Examples

For SIMD and SIMT programming:

In SIMD and SIMT programming, the address space qualifier must be explicitly used to indicate the address space. __gm__ indicates the Global Memory memory space, and __ubuf__ indicates the Unified Buffer memory space. No address space qualifier is required for the stack space.
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__simt_vf__ __launch_bounds__(1024) inline void KernelModff(__gm__ float* dst, __gm__ float* out, __gm__ float* x)
{
    int idx = threadIdx.x + blockIdx.x * blockDim.x;
    dst[idx] = modff(x[idx], out + idx); 
}