May 5, 2000 - Formatting Numbers | WebReference

# May 5, 2000 - Formatting Numbers

 May 5, 2000Formatting Numbers Tips: May 2000 Yehuda Shiran, Ph.D.Doc JavaScript
Until IE5.5, formatting numbers was a real challenge. We all used high mathematical functions such as `Math.ceil` and `Math.pow` to format numbers the way we wanted to. IE5.5 fixes this problem with three new methods of the `Number` prototype object:

``````toFixed(fractionDigits)
toExponential(fractionDigits)
toPrecision(precision) ``````

The `toFixed(fractionDigits)` method formats a number with `fractionDigits` digits after the decimal place. Suppose:

``x = 1234.56789``

and you call `alert(x.toFixed(4))`, you'll get `1234.5679` in IE5.5.

The `toExponential(fractionDigits)` method formats a number with `fractionDigits` digits after the decimal place, in exponential notation. Suppose:

``x = 1234.56789``

and you call `alert(x.toExponential(2))`, you'll get `1.23e+3` in IE5.5.

The `toPrecision(precision)` method formats a number with total precision number of digits, in exponential notation if needed. Suppose:

``x = 1234.56789``

and you call `alert(x.toPrecision(2))`, you'll get `1.2e+3` in IE5.5.

When you call `alert(x.toPrecision(9))`, you'll get `1234.56789` in IE5.5