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Math object

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The Math object allows the use of mathematical constants (such as pi) and functions (such as sine).
The Math object cannot be instantiated.
The members of the Math object are static, they can be accessed the through the Math object only (Math.member).

Syntax:

Using Math properties, such as pi:
var pi = Math.PI;
Using Math methods, such as sin:
Math.sin (x);

Members:

The Math object inherited from the Object.prototype object. The following lists only contain the members of the Math object.

Properties:

Property Support Description
E
Returns Euler's number (e, the base of the natural logarithm). Numerical value truncated to 4 decimal places: 2.7182.
LN2
Natural logarithm of 2. Numerical value truncated to 4 decimal places: 0.6931.
LN10
Natural logarithm of 10. Numerical value truncated to 4 decimal places: 2.3025.
LOG2E
Binary logarithm (logarithm for base 2) of Euler's number. Numerical value truncated to 4 decimal places: 1.4426.
LOG10E
Common logarithm (logarithm with base 10) of Euler's number. Numerical value truncated to 4 decimal places: 0.4342.
PI
Represents the ratio of any circle's circumference to its diameter in Euclidean geometry. 3.14159.
SQRT1_2
Square root of 1/2. Numerical value truncated to 4 decimal places: 0.7071.
SQRT2
The square root of 2, also known as Pythagoras' constant. Numerical value truncated to 4 decimal places: 1.4142.

Methods:

Method Support Description
abs (number)
Returns the absolute value of a floating-point number. In other words, returns the unsigned value of a real number.
number Required. Specifies a floating-point number.
acos (number)
Returns the arc cosine of the specified number, in radians.
number Required. Specifies a floating point number from -1 to 1.
asin (number)
Returns the arc sine of the specified number, in radians.
number Required. Specifies a floating point number from -1 to 1.
atan (number)
Returns the arc tangent of the specified number, in radians.
number Required. Specifies a floating point number.
atan2 (Y, X)
Returns the direction (angle) of the (X, Y) position vector (vector from origin to (X, Y)), in radians. Equivalent to atan (Y / X).
Y Required. The y-coordinate of the point.
X Required. The x-coordinate of the point.
ceil (number)
Returns the smallest integer that is greater than or equal to the given number.
number Required. Specifies a floating point number.
Example 2 shows different methods for converting floating point values to integers.
cos (angle)
Returns the cosine of the specified angle.
angle Required. A floating point number that specifies an angle, in radians.
exp (x)
Returns the value of ex, where e is Euler's number and x is the power.
x Required. Specifies a floating point number.
floor (number)
Returns the greatest integer that is smaller than or equal to the given number.
number Required. Specifies a floating point number.
Example 2 shows different methods for converting floating point values to integers.
log (number)
Returns the natural logarithm of the given number. Returns the power to which the base e (Euler's number) must be raised to obtain the given number.
number Required. Specifies a floating point number.
max ([number1 [, number2 [. . . [, numberN]]]])
Returns the greatest value from the specified numbers.
[number1 [, number2 [. . . [, numberN]]]] Required. Numbers to compare.
min ([number1 [, number2 [. . . [, numberN]]]])
Returns the smallest value from the specified numbers.
[number1 [, number2 [. . . [, numberN]]]] Required. Numbers to compare.
pow (base, exponent)
Returns the value of baseexponent, the base to the exponent power.
base Required. The base number.
exponent Required. The exponent.
random ()
Reruns a random number between 0 and 1.
round (number)
Returns the nearest integer for the given number.
number Required. Specifies a floating point number.
Example 2 shows different methods for converting floating point values to integers.
sin (angle)
Returns the sine of the specified angle.
angle Required. A floating point number that specifies an angle, in radians.
sqrt (number)
Returns the square root of the given number.
number Required. Specifies a floating point number.
tan (angle)
Returns the tangent of the specified angle.
angle Required. A floating point number that specifies an angle, in radians.

Examples:

Example 1:

How to get the value of pi:
var pi = Math.PI;
document.write (pi); // output: 3.141592653589793
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Example 2:

Converting floating point values to integers:
<head>
    <script type="text/javascript">
        function Init () {
            var tbody = document.getElementById ("tableBody");
            var values = [6.34, 6.94, -6.34, -6.94];
            for (var i = 0; i < values.length; i++) {
                var row = tbody.insertRow (-1);

                var cell = row.insertCell (-1);
                cell.innerHTML = values[i];
                var cell = row.insertCell (-1);
                cell.innerHTML = Math.round (values[i]);
                var cell = row.insertCell (-1);
                cell.innerHTML = Math.floor (values[i]);
                var cell = row.insertCell (-1);
                cell.innerHTML = Math.ceil (values[i]);
                var cell = row.insertCell (-1);
                cell.innerHTML = ~~values[i];
                var cell = row.insertCell (-1);
                cell.innerHTML = (values[i] ^ 0);
                var cell = row.insertCell (-1);
                cell.innerHTML = (values[i] << 0);
            }
        }
    </script>
</head>
<body onload="Init ()">
    <table border="1px" cellspacing="0" cellpadding="5px">
        <thead>
            <tr>
                <th>x</th>
                <th>Math.round (x)</th>
                <th>Math.floor (x)</th>
                <th>Math.ceil (x)</th>
                <th>~~x</th>
                <th>x ^ 0</th>
                <th>x << 0</th>
            </tr>
        </thead>
        <tbody id="tableBody">
        </tbody>
    </table>
</body>
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Example 3:

How to get a number's exponent:
var exp = Math.pow (2, 3);
document.write (exp); // output: 8
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Example 4:

How to generate a random number:
var random = Math.random ();
document.write (random); // output: a number between 0 and 1
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