Number Object
The Number object is an object wrapper for primitive numeric values. It
contains some useful methods, introduced in JavaScript 1.5.
Constructor:
new Number(value)
Number (value)
where "value" is the numeric value of the Number object to be created, or
value to be converted to a number.
Properties
Properties |
Description |
MAX_VALUE |
The largest representable number in JavaScript. |
MIN_VALUE |
The smallest representable number in JavaScript. |
NaN |
"Not a number" value. |
NEGATIVE_INFINITY |
Negative infinity, returned on overflow. |
POSITIVE_INFINITY |
Infinity, returned on overflow. |
prototype |
Prototype property, to add custom properties and
methods to this object. |
Methods
Methods |
Description |
toExponential(x) |
Returns a number in exponential notation (string
format). "x" should be a number between 0 and 20, dictating the
number of digits to include in the notation after the decimal place. |
toFixed(x) |
Formats any number for "x" number of trailing
decimals. The number is rounded up, and "0"s are used after the
decimal point if needed to create the desired decimal length.
Example(s) |
toPrecision(x) |
Formats any number so it is of "x" length. Also
called significant digits. A decimal point and "0"s are used if
needed to create the desired length. |
Note: All methods above are introduced in JavaScript 1.5, and only
supported in IE6+ and NS6+.
Examples
toFixed(x)
var profits=2489.8237
profits.toFixed(3) //returns 2489.824 (round up)
profits.toFixed(2) //returns 2489.82