---
title: vneg
description: "实数向量求负值运算。"
url: https://www.hikunpeng.com/document/detail/zh/kunpengaccel/system-lib/ug-kvsip/kunpengaccel_kvsip_06_0049.html
sourcePath: /source/zh/kunpengaccel/system-lib/ug-kvsip/kunpengaccel_kvsip_06_0049.html
indexId: 48e83e6d6b453deaff69cd44a07bcc41a581d334923d208c84c67e6b56471f4075
---
# vneg

实数向量求负值运算。

函数接口声明如下：

float型函数的操作：

void (vsip_vneg_f)(const vsip_vview_f *a, const vsip_vview_f *r);

#### 参数

| 参数名 | 描述 | 取值范围 | 输入/输出 |
| --- | --- | --- | --- |
| a | 指向源向量的指针。 | 非空 | 输入 |
| r | 指向目的向量的指针。 | 非空 | 输出 |


#### 异常输入

空指针输入时，函数直接返回。


#### 示例

```
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include "kvsip.h"
#include "vsip.h"
#include "vsip_type.h"

#define BUFFER_SIZE_T 10
void VnegExample()
{
    float src[BUFFER_SIZE_T] = {1.64f, 1.63f, -1.09f, 0.71f, -3.20f, -0.43f, 0.41f, -4.83f, 5.36f, -4.40f};
    float dst[BUFFER_SIZE_T];
    int64_t stride = 1;
    uint64_t offset = 0;

    vsip_block_f *block_a = vsip_blockbind_f(src, BUFFER_SIZE_T, VSIP_MEM_NONE);
    vsip_block_f *block_r = vsip_blockbind_f(dst, BUFFER_SIZE_T, VSIP_MEM_NONE);

    vsip_vview_f *a = vsip_vbind_f(block_a, offset, stride, BUFFER_SIZE_T);
    vsip_blockadmit_f(block_a, VSIP_TRUE);
    vsip_vview_f *r = vsip_vbind_f(block_r, offset, stride, BUFFER_SIZE_T);
    vsip_blockadmit_f(block_r, VSIP_TRUE);

    vsip_vneg_f(a, r);

    vsip_valldestroy_f(a);
    vsip_valldestroy_f(r);

    printf("src:\n");
    for (int32_t i = 0; i < BUFFER_SIZE_T; ++i) {
        printf("%.2f ", src[i]);
    }
    printf("\ndst:\n");
    for (int32_t i = 0; i < BUFFER_SIZE_T; ++i) {
        printf("%.2f ", dst[i]);
    }
    printf("\n");
}

int main(void) {
    VnegExample();
    return 0;
}
```

运行结果：

```
src:
1.64 1.63 -1.09 0.71 -3.20 -0.43 0.41 -4.83 5.36 -4.40
dst:
-1.64 -1.63 1.09 -0.71 3.20 0.43 -0.41 4.83 -5.36 4.40
```