andre/30-seconds-of-code
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Update geometricProgression.md

Browse Source
This commit is contained in:
Angelos Chalaris
2018-01-03 13:51:20 +02:00
committed by GitHub
parent e16f34405a
commit 9f4ed5333b
1 changed files with 6 additions and 5 deletions
Download Patch File Download Diff File Expand all files Collapse all files

11
snippets/geometricProgression.md
View File

@ -1,11 +1,12 @@
### geometricProgression
Initializes an array containing the numbers in the specified range where `start` and `end` are inclusive and the ratio between two terms is `step`.
Initializes an array containing the numbers in the specified range where `start` and `end` are inclusive and the ratio between two terms is `step`.
Returns an error if `step` equals `1`.
Use `Array.from()`, `Math.log()` and `Math.floor()` to create an array of the desired length, `Array.map()` to fill with the desired values in a range.
Omit the second argument, `start`, to use a default value of `1`.
Omit the third argument, `step`, to use a default value of `2`.
Use Array(Math.floor(Math.log(end/start)/Math.log(step))+1) to create an array of the desired length, Array.map() to fill with the desired values in a range.
You can omit `start` to use a default value of 1.
You can omit `step` to use a default value of 2.
Returns a error when you try to use `step = 1`
``` js
const geometricProgression = (end, start = 1,step = 2) =>
Array.from({ length:Math.floor(Math.log(end/start)/Math.log(step))+1}).map((v, i) => start * (step ** (i)) )