clamp function

Restricts a number to an interval.

import { clamp } from 'utils';

Signature

export function clamp(value: number, min = 0, max = 1): number

Parameters

Name	Description
value	The number to restrict.
min	The lower bound. Defaults to 0.
max	The upper bound. Defaults to 1.

Returns

value within the bounds, or the nearest bound.

Example

clamp(15, 0, 10); // 10
clamp(1.5); // 1

Tests

Line coverage: 100 %.

• ✅ clamps 5 into [0, 10] as 5
• ✅ clamps -5 into [0, 10] as 0
• ✅ clamps 15 into [0, 10] as 10
• ✅ clamps -5 into [10, 0] as 0
• ✅ takes the defaults

Source

src/math/clamp.ts (on GitHub)

Used by

• remap: Maps a value from an input range to an output range, such as a sensor reading to a gauge angle.
• createSvgBarRangePath: Creates the d of the part of a bar between two ratios, across its whole thickness, in any group: the fill level of a bar graph (0 to the value) or a threshold zone.

Source code

/**
 * Restricts a number to an interval.
 *
 * @param value - The number to restrict.
 * @param min - The lower bound. Defaults to `0`.
 * @param max - The upper bound. Defaults to `1`.
 * @returns `value` within the bounds, or the nearest bound.
 * @example
 * clamp(15, 0, 10); // 10
 * clamp(1.5); // 1
 */
export function clamp(value: number, min = 0, max = 1): number {
  return Math.min(Math.max(value, min), max);
}

Test file

import { clamp } from './clamp';

describe(clamp, () => {
  it.for([
    [5, 0, 10, 5],
    [-5, 0, 10, 0],
    [15, 0, 10, 10],
    [-5, 10, 0, 0],
  ] as const)('clamps %s into [%s, %s] as %s', ([value, min, max, expected]) => {
    expect(clamp(value, min, max)).toBe(expected);
  });

  it('takes the defaults', () => {
    expect(clamp(1.5)).toStrictEqual(clamp(1.5, 0, 1));
  });
});

Keywords: clamp, math, function