@basementuniverse/utils v1.4.0
utils
A small library of useful functions
Usage
Node:
const utils = require('@basementuniverse/utils');
Browser:
<script src="utils.js"></script>
Typescript:
import * as utils from '@basementuniverse/utils';
Contents
Functions
Typedefs
floatEquals(a, b, p) ⇒ boolean
Check if two numbers are approximately equal
Kind: global function
Returns: boolean - True if numbers a and b are approximately equal
Param | Type | Default | Description |
---|---|---|---|
a | number | Number a | |
b | number | Number b | |
p | number | Number.EPSILON | The precision value |
clamp(a, min, max) ⇒ number
Clamp a number between min and max
Kind: global function
Returns: number - A clamped number
Param | Type | Default | Description |
---|---|---|---|
a | number | The number to clamp | |
min | number | 0 | The minimum value |
max | number | 1 | The maximum value |
frac(a) ⇒ number
Get the fractional part of a number
Kind: global function
Returns: number - The fractional part of the number
Param | Type | Description |
---|---|---|
a | number | The number from which to get the fractional part |
round(n, d) ⇒ number
Round n to d decimal places
Kind: global function
Returns: number - A rounded number
Param | Type | Default | Description |
---|---|---|---|
n | number | The number to round | |
d | number | 0 | The number of decimal places to round to |
lerp(a, b, i) ⇒ number
Do a linear interpolation between a and b
Kind: global function
Returns: number - An interpolated value in the interval a, b
Param | Type | Description |
---|---|---|
a | number | The minimum number |
b | number | The maximum number |
i | number | The interpolation value, should be in the interval 0, 1 |
unlerp(a, b, i) ⇒ number
Get the position of i between a and b
Kind: global function
Returns: number - The position of i between a and b
Param | Type | Description |
---|---|---|
a | number | The minimum number |
b | number | The maximum number |
i | number | The interpolated value in the interval a, b |
blerp(c00, c10, c01, c11, ix, iy) ⇒ number
Do a bilinear interpolation
Kind: global function
Returns: number - A bilinear interpolated value
Param | Type | Description |
---|---|---|
c00 | number | Top-left value |
c10 | number | Top-right value |
c01 | number | Bottom-left value |
c11 | number | Bottom-right value |
ix | number | Interpolation value along x |
iy | number | Interpolation value along y |
remap(i, a1, a2, b1, b2) ⇒ number
Re-map a number i from range a1...a2 to b1...b2
Kind: global function
Param | Type | Description |
---|---|---|
i | number | The number to re-map |
a1 | number | |
a2 | number | |
b1 | number | |
b2 | number |
smoothstep(a, b, i) ⇒ number
Do a smooth interpolation between a and b
Kind: global function
Returns: number - An interpolated value in the interval a, b
Param | Type | Description |
---|---|---|
a | number | The minimum number |
b | number | The maximum number |
i | number | The interpolation value |
radians(degrees) ⇒ number
Get an angle in radians
Kind: global function
Returns: number - The angle in radians
Param | Type | Description |
---|---|---|
degrees | number | The angle in degrees |
degrees(radians) ⇒ number
Get an angle in degrees
Kind: global function
Returns: number - The angle in degrees
Param | Type | Description |
---|---|---|
radians | number | The angle in radians |
randomBetween(min, max) ⇒ number
Get a random float in the interval [min, max)
Kind: global function
Returns: number - A random float in the interval [min, max)
Param | Type | Description |
---|---|---|
min | number | Inclusive min |
max | number | Exclusive max |
randomIntBetween(min, max) ⇒ number
Get a random integer in the interval min, max
Kind: global function
Returns: number - A random integer in the interval min, max
Param | Type | Description |
---|---|---|
min | number | Inclusive min |
max | number | Inclusive max |
cltRandom(mu, sigma, samples) ⇒ number
Get a normally-distributed random number
Kind: global function
Returns: number - A normally-distributed random number
Param | Type | Default | Description |
---|---|---|---|
mu | number | 0.5 | The mean value |
sigma | number | 0.5 | The standard deviation |
samples | number | 2 | The number of samples |
cltRandomInt(min, max) ⇒ number
Get a normally-distributed random integer in the interval min, max
Kind: global function
Returns: number - A normally-distributed random integer
Param | Type | Description |
---|---|---|
min | number | Inclusive min |
max | number | Inclusive max |
weightedRandom(w) ⇒ number
Return a weighted random integer
Kind: global function
Returns: number - An index from w
Param | Type | Description |
---|---|---|
w | Array.<number> | An array of weights |
lerpArray(a, i, f) ⇒ number
Return an interpolated value from an array
Kind: global function
Returns: number - An interpolated value in the interval min(a), max(a)
Param | Type | Default | Description |
---|---|---|---|
a | Array.<number> | An array of values interpolate | |
i | number | A number in the interval 0, 1 | |
f | InterpolationFunction | Math.lerp | The interpolation function to use |
dot(a, b) ⇒ number
Get the dot product of two vectors
Kind: global function
Returns: number - a ∙ b
Param | Type | Description |
---|---|---|
a | Array.<number> | Vector a |
b | Array.<number> | Vector b |
factorial(a) ⇒ number
Get the factorial of a number
Kind: global function
Returns: number - a!
Param | Type |
---|---|
a | number |
npr(n, r) ⇒ number
Get the number of permutations of r elements from a set of n elements
Kind: global function
Returns: number - nPr
Param | Type |
---|---|
n | number |
r | number |
ncr(n, r) ⇒ number
Get the number of combinations of r elements from a set of n elements
Kind: global function
Returns: number - nCr
Param | Type |
---|---|
n | number |
r | number |
combinations(a, r) ⇒ Array.<Array.<*>>
Generate all combinations of r elements from an array
Kind: global function
Returns: Array.<Array.<*>> - An array of combination arrays
Param | Type | Description |
---|---|---|
a | Array.<*> | |
r | number | The number of elements to choose in each combination |
Example
combinations([1, 2, 3], 2);
Output:
[
[1, 2],
[1, 3],
[2, 3]
]
cartesian()
Get a cartesian product of arrays
Kind: global function
Example
cartesian([1, 2, 3], ['a', 'b']);
Output:
[
[1, "a"],
[1, "b"],
[2, "a"],
[2, "b"],
[3, "a"],
[3, "b"]
]
times(f, n) ⇒ Array.<*>
Return a new array with length n by calling function f(i) on each element
Kind: global function
Param | Type | Description |
---|---|---|
f | TimesFunction | |
n | number | The size of the array |
range(n) ⇒ Array.<number>
Return an array containing numbers 0->(n - 1)
Kind: global function
Returns: Array.<number> - An array of integers 0->(n - 1)
Param | Type | Description |
---|---|---|
n | number | The size of the array |
zip(a, b) ⇒ Array.<Array.<*>>
Zip 2 arrays together, i.e. (1, 2, 3, a, b, c) => [1, a, 2, b, 3, c]
Kind: global function
Param | Type |
---|---|
a | Array.<*> |
b | Array.<*> |
at(a, i) ⇒ *
Return arrayi with positive and negative wrapping
Kind: global function
Returns: * - An element from the array
Param | Type | Description |
---|---|---|
a | Array.<*> | |
i | number | The positively/negatively wrapped array index |
peek(a) ⇒ *
Return the last element of an array without removing it
Kind: global function
Returns: * - The last element from the array
Param | Type |
---|---|
a | Array.<*> |
chunk(a, n) ⇒ Array.<Array.<*>>
Chop an array into chunks of size n
Kind: global function
Returns: Array.<Array.<*>> - An array of array chunks
Param | Type | Description |
---|---|---|
a | Array.<*> | |
n | number | The chunk size |
shuffle(a) ⇒ Array.<*>
Randomly shuffle a shallow copy of an array
Kind: global function
Returns: Array.<*> - The shuffled array
Param | Type |
---|---|
a | Array.<*> |
flat(o, concatenator) ⇒ object
Flatten an object
Kind: global function
Returns: object - A flattened object
Param | Type | Default | Description |
---|---|---|---|
o | object | ||
concatenator | string | "." | The string to use for concatenating keys |
unflat(o, concatenator) ⇒ object
Unflatten an object
Kind: global function
Returns: object - An un-flattened object
Param | Type | Default | Description |
---|---|---|---|
o | object | ||
concatenator | string | "." | The string to check for in concatenated keys |
split(array, predicate) ⇒ Array.<Array.<*>>
Split an array into sub-arrays based on a predicate
Kind: global function
Returns: Array.<Array.<*>> - An array of arrays
Param | Type |
---|---|
array | Array.<*> |
predicate | SplitPredicate |
pluck(o, ...keys) ⇒ object
Pluck keys from an object
Kind: global function
Returns: object - An object containing the plucked keys
Param | Type | Description |
---|---|---|
o | object | |
...keys | string | The keys to pluck from the object |
exclude(o, ...keys) ⇒ object
Exclude keys from an object
Kind: global function
Returns: object - An object containing all keys except excluded keys
Param | Type | Description |
---|---|---|
o | object | |
...keys | string | The keys to exclude from the object |
InterpolationFunction ⇒ number
An interpolation function
Kind: global typedef
Returns: number - The interpolated value in the interval a, b
Param | Type | Description |
---|---|---|
a | number | The minimum number |
b | number | The maximum number |
i | number | The interpolation value, should be in the interval 0, 1 |
TimesFunction ⇒ *
A function for generating array values
Kind: global typedef
Returns: * - The array value
Param | Type | Description |
---|---|---|
i | number | The array index |
SplitPredicate ⇒ boolean
A split predicate
Kind: global typedef
Returns: boolean - True if the array should split at this index
Param | Type | Description |
---|---|---|
value | any | The current value |