Add InitializeArrayWithRangeRight.md

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Angelos Chalaris
2018-01-16 17:09:39 +02:00
parent 447e3467db
commit e8616e54fb
3 changed files with 20 additions and 1 deletions

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### initializeArrayWithRange ### initializeArrayWithRange
Initializes an array containing the numbers in the specified range where `start` and `end` are inclusive with there common difference `step`. Initializes an array containing the numbers in the specified range where `start` and `end` are inclusive with their common difference `step`.
Use `Array.from(Math.ceil((end+1-start)/step))` to create an array of the desired length(the amounts of elements is equal to `(end-start)/step` or `(end+1-start)/step` for inclusive end), `Array.map()` to fill with the desired values in a range. Use `Array.from(Math.ceil((end+1-start)/step))` to create an array of the desired length(the amounts of elements is equal to `(end-start)/step` or `(end+1-start)/step` for inclusive end), `Array.map()` to fill with the desired values in a range.
You can omit `start` to use a default value of `0`. You can omit `start` to use a default value of `0`.

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### initializeArrayWithRangeRight
Initializes an array containing the numbers in the specified range (in reverse) where `start` and `end` are inclusive with their common difference `step`.
Use `Array.from(Math.ceil((end+1-start)/step))` to create an array of the desired length(the amounts of elements is equal to `(end-start)/step` or `(end+1-start)/step` for inclusive end), `Array.map()` to fill with the desired values in a range.
You can omit `start` to use a default value of `0`.
You can omit `step` to use a default value of `1`.
```js
const initializeArrayWithRangeRight = (end, start = 0, step = 1) =>
Array.from({ length: Math.ceil((end + 1 - start) / step) }).map((v, i, arr) => (arr.length - i - 1) * step + start);
```
```js
initializeArrayWithRangeRight(5); // [5,4,3,2,1,0]
initializeArrayWithRangeRight(7, 3); // [7,6,5,4,3]
initializeArrayWithRangeRight(9, 0, 2); // [8,6,4,2,0]
```

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@ -75,6 +75,7 @@ indexOfAll:array
initial:array initial:array
initialize2DArray:array initialize2DArray:array
initializeArrayWithRange:array,math initializeArrayWithRange:array,math
initializeArrayWithRangeRight:array,math
initializeArrayWithValues:array,math initializeArrayWithValues:array,math
inRange:math inRange:math
intersection:array,math intersection:array,math