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JavaScript

Posted by Rebecca Jensen
Rebecca Jensen
11,580 Points

Can I perform Math.max() on a named array?

I've written some code that looks at an array of strings that are numbers, and adds up each string of numbers (e.g. '123' becomes 6). Now I want to compare the integers in the array (I did convert them to integers), to find the largest number. I am trying to use Math.max() to do that, but it doesn't seem to work when I call the name of my array to it.

Can I use Math.max() to do this? Do I need to do more to the array first to prepare it for Math.max()? Should I use another method?

Thanks

Code here: https://repl.it/I0e5/21

And below:

var ccNumbers = ['1111','--34-1234', '21-11', '3111', '9111'];


function addDigits(number){

    var sum = 0; //store the sum
    var sumArray = [];//store several sums to print

    for ( x = 0; x < ccNumbers.length; x++ ) { //loop through ccNumbers array 
      var ccNmbr = ccNumbers[x]; //pick out one array item and store it in ccNmbr

        for ( z = 0; z < ccNmbr.length; z++) {
          ccNmbr = ccNmbr.replace("-", 0);
          ccNmbr = ccNmbr.replace(" ", 0);
        } //removes dashes, replaces with 0's, to avoid NaN 

      for ( y = 0; y < ccNmbr.length; y++ ) { //loop through each digit in ccNmbr 
      sum += parseInt(ccNmbr.charAt(y), 10); //add each digit to the sum

      } //close adding digits loop

   sumArray.push(sum); //add sum to an array
   sum = 0; //reset sum to 0 for the next loop 

    } //close looping through array loop

    largest = Math.max(sumArray);

    return largest;

}

addDigits();

1 Answer

james south
.a{fill-rule:evenodd;}techdegree seal-36
james south
Front End Web Development Techdegree Graduate 33,271 Points

yes. use the spread operator ... let max = Math.max(...myArray);

Rebecca Jensen
Rebecca Jensen
11,580 Points

A spread operator! Was just what I needed. I'm surprised I didn't encounter it in all of my Googling. Now that I have a term to search, I've found an article on other cool ways to use this: https://davidwalsh.name/spread-operator

Thanks!