[Home](./index.md) > [@three3d/effect](./effect.md) > [getNearbyIndex](./effect.getnearbyindex.md) ## getNearbyIndex() function 获取 target 附近的索引 **Signature:** ```typescript export declare function getNearbyIndex(sortedNums: ArrayLike, target: number, right?: boolean): number; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | sortedNums | ArrayLike<number> | 按照从小到大顺序数字数组 | | target | number | 目标值 | | right | boolean | _(Optional)_ 是否获取目标值右侧的索引； | **Returns:** number 当返回 -1 时，表示没找到