Skip to content

meanBy

Import from @varavel/vdl-plugin-sdk/utils/math.

function meanBy<T>(items, getValue): number;

Calculates the average of an array of numbers when applying the getValue function to each element.

If the array is empty, this function returns NaN.

Type Parameters

Type Parameter Description
T The type of elements in the array.

Parameters

Parameter Type Description
items readonly T[] An array to calculate the average.
getValue (element) => number A function that selects a numeric value from each element.

Returns

number

The average of all the numbers as determined by the getValue function.

Example

meanBy([{ a: 1 }, { a: 2 }, { a: 3 }], x => x.a); // Returns: 2
meanBy([], x => x.a); // Returns: NaN