math

Adds two values.

Type signature

(a: number, b: number) => number

Examples

add(3, 5);
// ⇒ 8
Try in REPL

Questions

  • How to add two values?

TypeScript sourceJavaScript source

Calculates the average of the given array of numbers.

Type signature

(xs?: number[]) => number

Examples

average([2, 4, 15]);
// ⇒ 7
Try in REPL

Questions

  • How to compute the average of an array?

TypeScript sourceJavaScript source

Finds the nearest power of two greater or equal to the given value.

Type signature

(x: number) => number

Examples

ceilToNearestPowerOfTwo(345);
// ⇒ 512
Try in REPL

Questions

  • How to get the nearest power of two greater or equal to the given value?

TypeScript sourceJavaScript source

Clamps the given value to the given range.

Type signature

(min: number, max: number) => ((x: number) => number)

Examples

clamp(0, 10)(5);
// ⇒ 5
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clamp(0, 10)(-5);
// ⇒ 0
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clamp(0, 10)(15);
// ⇒ 10
Try in REPL

Questions

  • How to clamp value to the desired range?
  • How to enforce a value to be in a given range?

TypeScript sourceJavaScript source

Clamps the given value to the [0, 1] range.

Type signature

(x: number) => number

Examples

clampNormal(0.5);
// ⇒ 0.5
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clampNormal(-0.5);
// ⇒ 0
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clampNormal(1.5);
// ⇒ 1
Try in REPL

Questions

  • How to clamp value to be in 0 to 1 inclusive range?
  • How to clamp value to be in the normal range?

TypeScript sourceJavaScript source

Clamps the given value to the [0, 100] range.

Type signature

(x: number) => number

Examples

clampPercentage(50);
// ⇒ 50
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clampPercentage(-50);
// ⇒ 0
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clampPercentage(150);
// ⇒ 100
Try in REPL

Questions

  • How to enforce a percentage be between 0% and 100%?

TypeScript sourceJavaScript source

Calculates the absolute distance between given values.

Type signature

(a: number, b: number) => number

Examples

delta(-3, 5);
// ⇒ 8
Try in REPL

Questions

  • How to calculate an absolute distance between two numbers?

TypeScript sourceJavaScript source

Checks if the given value is in the rectangular range of [0, width] and [0, height]

Type signature

(width: number, height: number) => ((x: number, y: number) => boolean)

Examples

inRectangleRange(50, 100)(25, 50);
// ⇒ true
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inRectangleRange(50, 100)(-25, 50);
// ⇒ false
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Questions

  • How to check if a point is inside a rectangle defined by width and height?

TypeScript sourceJavaScript source

Linearly interpolates two given values by the normal value of their distance.

Type signature

(t: number) => ((a: number, b: number) => number)

Examples

lerp(0.5)(0, 10);
// ⇒ 5
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lerp(0)(0, 10);
// ⇒ 0
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lerp(1)(0, 10);
// ⇒ 10
Try in REPL

Questions

  • How to linearly interpolate between two values?
  • How to interpolate two numbers?

TypeScript sourceJavaScript source

Calculates the maximum by a given selector.

Type signature

(f: (x: number) => number) => ((xs: number[]) => number)

Examples

maximumBy(({ age }) => age)([
  { age: 13 },
  { age: 20 },
  { age: 7 },
  { age: 18 },
]);
// ⇒ { age: 20 }
Try in REPL

Questions

  • How to find a maximum element by a given function?

TypeScript sourceJavaScript source

Calculates the median of the values. If there is an even number of items, the average of the middle ones is returned.

Type signature

(xs?: number[]) => number | undefined

Examples

median([-5, 3, 2, 29, 43]);
// ⇒ 3
Try in REPL

Questions

  • How to compute a median of an array?

TypeScript sourceJavaScript source

Calculates the minimum and maximum value of the two given values.

Type signature

([a, b]: [number, number]) => [number, number]

Examples

minMax([5, 3]);
// ⇒ [3, 5]
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minMax([3, 5]);
// ⇒ [3, 5]
Try in REPL

Questions

  • How to get ordered values where the lower is the first and the higher is the second?

TypeScript sourceJavaScript source

Checks if all the given values have the same sign.

Type signature

(xs: number[]) => boolean

Examples

sameSign([-1, -2, -3]);
// ⇒ true
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sameSign([1, 2, -3]);
// ⇒ false
Try in REPL

Questions

  • How to check if all values have the same sign?

TypeScript sourceJavaScript source

Calculates the sign of the value and returns -1 for negative values, 1 for positive values and 0 for zeros.

Type signature

(x: number) => number

Examples

sign(3);
// ⇒ 1
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sign(-5);
// ⇒ 5
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sign(0);
// ⇒ 0
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sign(-0);
// ⇒ 0
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Questions

  • How to get a sign of a number?

TypeScript sourceJavaScript source

Calculates the standard deviation of the given array of numbers.

Type signature

(xs: number[], origin?: number) => number

Examples

standardDeviation([
  96, 81, 68, 79, 23, 13, 13, 59,
  44, 86,
]);
// ⇒ (2 * Math.sqrt(10922 / 5)) / 3
Try in REPL

Questions

  • How to compute a standard deviation of an array?

TypeScript sourceJavaScript source

Subtracts two values.

Type signature

(a: number, b: number) => number

Examples

subtract(3, 5);
// ⇒ -2
Try in REPL

Questions

  • How to subtract two numbers?

TypeScript sourceJavaScript source