@cycxllin/cmpt315-a2/findNaNIndex.js

Fulfills CMPT 315 Assignment 2, MacEwan University Winter 2024.

/*
Find all the indexes where NaN is found in a given array of numbers and NaN.
Assumption: non-NaN types in an array are not NaN; 
    ie. we are looking for the number-NaN type specifically, not NaN=not a number
Parameters: array
Returns: array of numbers indicating indicies where NaN is present, 
    empty array if no NaN present,
    -1 if error occurs
*/

function findNaNIndex(arr){
    if (Array.isArray(arr)){
        let indicies = [];
        arr.forEach( (element, index) => {
            if (Number.isNaN(element)){
                indicies.push(index);
            }
        });
        
        return indicies;

    } else {
        console.error("Error: Parameter passed is not an array");
        return -1;
    }
}

module.exports = findNaNIndex;