[Home](./index.md) > [@essex/toolbox](./toolbox.md) > [interpolate](./toolbox.interpolate.md) ## interpolate variable Interpolates a data list, filling in the specified multiple. This returns a list of numberic values. The input does not have to be numeric, but if it isn't an accessor function should be supplied. Note that this just performs linear interpolation Signature: ```typescript interpolate: (data: any[], multiple: number, accessor?: (d: any) => any) => number[] ```