---
title: kml_?_interp2d_idx
description: "返回网格(i, j)点的index，index的值为j * xsize + i。"
url: https://www.hikunpeng.com/document/detail/zh/kunpenghpcs/hpckit/devg/kunpengaccel_kml_0527.html
sourcePath: /source/zh/kunpenghpcs/hpckit/devg/kunpengaccel_kml_0527.html
indexId: 987f0bb1f52d9b5c4d6113afb2807fe65614971e1f7c58feac513bb2f079852f61
---
# kml_?_interp2d_idx

返回网格(i, j)点的index，index的值为j * xsize + i。

#### 接口定义

size_t kml_float_interp2d_idx(const kml_float_interp2d *interp, const size_t i, const size_t j)

size_t kml_double_interp2d_idx(const kml_double_interp2d *interp, const size_t i, const size_t j);


#### 参数

| 参数名 | 类型 | 描述 | 输入/输出 |
| --- | --- | --- | --- |
| interp | const kml\_float\_interp2d\* / const kml\_double\_interp2d\* | 指向插值对象的指针。 | 输入 |
| i | size\_t | x方向的index。 | 输入 |
| j | size\_t | y方向的index。 | 输入 |


#### 依赖

#include "kipl.h"


#### 示例

```
const size_t xSize = 4;
const size_t ySize = 4;
float xArr[4] = {1,1.33,1.67,2};
float yArr[4] = {1,1.33,1.67,2};
float* zArr = (float*)malloc(xSize * ySize * sizeof(float));
size_t x = 1;
size_t y = 1;
kml_float_interp2d *interp = kml_float_interp2d_alloc(kml_float_interp2d_bicubic, xSize, ySize);
kml_float_interp2d_init(interp, xArr, yArr, zArr, xSize, ySize);
size_t idx = kml_float_interp2d_idx(interp, x, y);
```