How to get the index of each element of an array based on the indexes of the same elements in a diff-CodePudding

My array of reference is "functionsvalues", which presents the elements: 'All', 'Fe', 'Fi', 'Te', 'Ti', 'Se', 'Si', 'Ne', 'Ni' in the correct order.

Now I need to get a list of numbers the will express the order of these same elements rearranged, is this case: 'Fe', 'Si', 'Ne', 'Ti', 'Fi', 'Se', 'Ni', 'Te'

Array of reference: functionsvalues = ['All', 'Fe', 'Fi', 'Te', 'Ti', 'Se', 'Si', 'Ne', 'Ni']

Array for which I want the custom order: chosenfunctionsvalues = ['Fe', 'Si', 'Ne', 'Ti', 'Fi', 'Se', 'Ni', 'Te']

Desired output: [1, 6, 7, 4, 2, 5, 8, 3]

CodePudding user response：

You could take an object and map the indices.

const
    values = ['All', 'Fe', 'Fi', 'Te', 'Ti', 'Se', 'Si', 'Ne', 'Ni'],
    indices = Object.fromEntries(values.map((k, i) => [k, i])),
    given = ['Fe', 'Si', 'Ne', 'Ti', 'Fi', 'Se', 'Ni', 'Te'],
    result = given.map(k => indices[k]);

console.log(...result);

CodePudding user response：

This is what you can do.

var arr = ['All', 'Fe', 'Fi', 'Te', 'Ti', 'Se', 'Si', 'Ne', 'Ni'];

var anotherArray = ['Fe', 'Si', 'Ne', 'Ti', 'Fi', 'Se', 'Ni', 'Te'];


var mapofIndices = {};
arr.forEach((a, i)=>{
 mapofIndices[a] = i;
})
var result = anotherArray.map(x=>mapofIndices[x])
console.log(result)