In JavaScript, you can negate a number (i.e. convert a positive number to negative, and a negative to positive) in the following ways:

## Using Unary Negation Operator

You may negate a number using the unary negation operator (`-`

) like so:

-n

This would convert a positive number to a negative number, and a negative number to a positive number. For example, you can use this in the following way:

// ES6+ const negate = (num) => -num; console.log(negate(1234)); // -1234 console.log(negate(-1234)); // 1234 console.log(negate(0)); // -0 console.log(negate(-0)); // 0

You can rewrite the "`negate`

" function as a function declaration/statement (instead of using arrow function), to support versions of ES prior to version 6.

## Using Arithmetic Operators

You may convert a positive number to negative or vice versa by simply multiplying it by `-1`

:

n * -1

Similarly, you may also divide the number by `-1`

to negate it:

n / -1

You could use *either* of these, for example, like so:

const negate = (num) => num * -1; console.log(negate(1234)); // -1234 console.log(negate(-1234)); // 1234 console.log(negate(0)); // -0 console.log(negate(-0)); // 0

const negate = (num) => num / -1; console.log(negate(1234)); // -1234 console.log(negate(-1234)); // 1234 console.log(negate(0)); // -0 console.log(negate(-0)); // 0

As an alternative to dividing and multiplying by `-1`

, you may subtract the number from `0`

instead:

0 - n

One important difference in subtracting the number from `0`

is the fact that this returns `0`

for both, positive and negative `0`

. This is different from dividing and multiplying by `-1`

, which returns `-0`

when `0`

is negated.

For example, you could use it in the following way:

const negate = (num) => 0 - num; console.log(negate(1234)); // -1234 console.log(negate(-1234)); // 1234 console.log(negate(0)); // 0 console.log(negate(-0)); // 0

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