I have a collection of data here, you can see below.
What I want is to get the index of that element that has a unique value in array.
var setArray = [ false, true, false, false ]
// Sample result will be 1, the index of unique value in array is true
// and has a index of 1
// code here to get the index...
How can I solve this?
var setArray = [ false, true, false, false ]
function singles( array ) {
for( var index = 0, single = []; index < array.length; index++ ) {
if( array.indexOf( array[index], array.indexOf( array[index] ) + 1 ) == -1 ) single.push( index );
};
return single;
};
singles(setArray); //This will return 1
A slightly modified function by ThinkingStiff on this question to suit your needs. Just pass in your array, and it'll return the index value of the unique element! That simple. Let me know how it goes.
Have you tried the following algorithm: for every item in the array find the index of first occurence and the index of the next occurence. If the index of next occurence is -1, then it is unique.
var setArray = [ false, true, false, false ];
var unique = [];
setArray.forEach(item => {
let firstIndex = setArray.indexOf(item, 0);
let secondIndex = setArray.indexOf(item, firstIndex + 1);
if(secondIndex < 0) {
unique.push(firstIndex);
}
});
See following fiddle for example:
https://jsfiddle.net/yt24ocbs/
This code will return an array of indexes of all unique elements in array. It accepts different types of values: string, number, boolean.
"use strict";
let strings = ["date1", "date", false, "name", "sa", "sa", "date1", 5, "8-()"];
let result = [];
let data = strings.reduce((acc, el) => {
acc[el] = (acc[el] || 0) + 1;
return acc;
}, {});
let keys = Object.keys(data);
for (let i = 0, max = keys.length; i < max; i++) {
if (data[keys[i]] === 1) {
let index = strings.indexOf(keys[i]);
if (index === -1) {
index = strings.indexOf(+keys[i]);
}
if (index === -1) {
index = strings.indexOf(keys[i] === true);
}
result.push(index);
}
}
result.sort( (a, b) => {return a - b});
console.log(result);You could map the indices for unique values and then filter just the index.
var array = [false, true, false, false],
result = array
.map(function (a, i, aa) { return aa.indexOf(a) === aa.lastIndexOf(a) ? i : -1; })
.filter(function (a) { return ~a; });
console.log(result[0]);ES6
var array = [false, true, false, false],
result = array
.map((a, i, aa) => aa.indexOf(a) === aa.lastIndexOf(a) ? i : -1)
.filter(a => ~a);
console.log(result[0]);
