is-close
v1.3.3
Published
Check if two numbers are equal within a given tolerance
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is-close
Check if either:
- two numbers are equal within a given tolerance
- the values in two arrays of numbers are equal within a given tolerance
isClose(a, b, rtol, atol, equalNaN, isCloseScaler) ⇒ boolean
|Array<boolean>
Check if a
is approximately equal to b
.
This check uses similar logic to Python math.isClose. By default values are considered to be close if:
abs(a - b) <= max(rtol * max(abs(a), abs(b)), atol).
Returns: boolean
- Returns true if both a
and b
are considered to be close.
| Parameter | Type | Description |
| ---------------- | --- | --- |
| a
| number
| First value to compare |
| b
| number
| Second value to compare |
| rtol
| number [optional]
| The relative tolerance parameter[default = 1e-09] |
| atol
| number [optional]
| The absolute tolerance parameter[default = 0.0] |
| equalNaN
| boolean [optional]
| Whether to compare NaNs as equal.If true, when a
is NaN and b
is NaN they will be considered equal.[default = false] |
| isCloseScaler
| IsCloseScaler [optional]
| Method used to scale the absolute difference into a relative difference.[default = IsCloseScalers.maxAbsAOrB] |
Overload
Returns: Array<boolean>
- Returns an array of booleans corresponding to the result of calling isClose() on the individual values in the arrays a
and b
.
| Parameter | Type | Description |
| ---------------- | --- | --- |
| a
| Array<number>
| First value to compare |
| b
| Array<number>
| Second value to compare |
| rtol
| number [optional]
| The relative tolerance parameter[default = 1e-09] |
| atol
| number [optional]
| The absolute tolerance parameter[default = 0.0] |
| equalNaN
| boolean [optional]
| Whether to compare NaNs as equal.[default = false] |
| isCloseScaler
| IsCloseScaler [optional]
| Method used to scale the absolute difference into a relative difference.[default = IsCloseScalers.maxAbsAOrB] |
IsCloseScalers#maxAbsAOrB(a, b) => number
Returns: number
- Relative difference scaling: Max(|a|,|b|)
IsCloseScalers#maxAOrB(a, b) => number
Returns: number
- Relative difference scaling: Max(a,b)
IsCloseScalers#minAbsAOrB(a, b) => number
Returns: number
- Relative difference scaling: Min(|a|,|b|)
IsCloseScalers#minAOrB(a, b) => number
Returns: number
- Relative difference scaling: Min(a,b)
IsCloseScalers#meanAbs(a, b) => number
Returns: number
- Relative difference scaling: Mean: (|a|+|b|)/2, using Welford's method
IsCloseScalers#mean(a, b) => number
Returns: number
- Relative difference scaling: Mean: (a+b)/2, using Welford's method
IsCloseScalers#absA(a) => number
Returns: number
- Relative error scaling: abs(a)
IsCloseScalers#absB(a, b) => number
Returns: number
- Relative error scaling: abs(b)
Installation
npm install is-close --save
Example Usage
var isClose = require("is-close");
// Examples of checking relative difference between first two parameters
console.log(isClose.isClose(1e-7, 1e-8));
console.log(isClose.isClose(1e10, 1.0000000001e10));
console.log(isClose.isClose([1e-7, 1e10], [1e-8, 1.0000000001e10]));
// Examples of relative error relative to first parameter
// - note how result is not symmetric
console.log(isClose.isClose(1.0, 0.9, 0.1, undefined, undefined, isClose.IsCloseScalers.absA));
console.log(isClose.isClose(0.9, 1.0, 0.1, undefined, undefined, isClose.IsCloseScalers.absA));
Output should be
false
true
[false, true]
true
false
TypeScript
import { isClose, IsCloseScalers } from 'is-close';
// Examples of checking relative difference between first two parameters
console.log(isClose(1.0, 1.000000001));
console.log(isClose(1.0, 1.0000000001));
console.log(isClose([1.0, 1.0], [1.000000001, 1.0000000001]));
// Examples of relative error relative to first parameter
// - note how result is not symmetric
console.log(isClose(1.0, 0.9, 0.1, undefined, undefined, IsCloseScalers.absA));
console.log(isClose(0.9, 1.0, 0.1, undefined, undefined, IsCloseScalers.absA));
Output should be
false
true
[false, true]
true
false
License
MIT © Steve Bosman