In the following short script (running in my browser):

var ages = [23, 22, 4, 101, 14, 78, 90, 2, 1, 89, 19];

const ages3 = ages.map(function(age) {
    return Math.sqrt(age) + "<br/>";
});

document.write(ages3);

In the following short script (running in my browser):

var ages = [23, 22, 4, 101, 14, 78, 90, 2, 1, 89, 19];

const ages3 = ages.map(function(age) {
    return Math.sqrt(age) + "<br/>";
});

document.write(ages3);

I would like to print a column of square root values in the most concise manner possible (ideally using the map method above). I attempted to chain a join, e.g., return age.join(' ').Math.sqrt(age) + "<br/>"; but that was unsuccessful (no output was produced).

Thank you.

• javascript

5 Answers 5

My solution using join and map.

var ages = [23, 22, 4, 101, 14, 78, 90, 2, 1, 89, 19];

document.write(
  ages.map(a => Math.sqrt(a))
  .join("<br>")
);

I think this solution is pretty concise and does just what you want.

If you want to produce a (single) HTML string to output, you should use reduce instead. .map is for when you want to transform an array into another array.

const ages = [23, 22, 4, 101, 14, 78, 90, 2, 1, 89, 19];
const ages3 = ages.reduce(function(accum, age) {
    return accum + Math.sqrt(age) + "<br/>";
}, '');
document.write(ages3);

You were on the right track. Just join() the newly mapped array ages3

var ages = [23, 22, 4, 101, 14, 78, 90, 2, 1, 89, 19];

const ages3 = ages.map(function(age) {
    return Math.sqrt(age) + "<br/>";
});

document.write(ages3.join(' '));

Alternatively you can use array.from

const ages = [23, 22, 4, 101, 14, 78, 90, 2, 1, 89, 19];
document.write(Array.from(ages, x => Math.sqrt(x)).join('<br\>'));

if you want new line between result then you can pass < br / > in side join function just line this:- return Math.sqrt(age).join('<br>'); if you want space between result then you can pass empty string in join function jus like this:- return Math.sqrt(age).join(' '); or if you want nothing then you can pas nothing inside jpin function just like this:- return Math.sqrt(age).join('');

var ages = [23, 22, 4, 101, 14, 78, 90, 2, 1, 89, 19];

const ages3 = ages.map(function(age) {
    return Math.sqrt(age).join('<br\>');
    // return Math.sqrt(age).join(' ');
    // return Math.sqrt(age).join('');
});

document.write(ages3);