Math in ECMAScript 262
A global, non-instantiable object which holds certain math-related functions and values.
Inherits from:
Self Methods
name | returns | description |
---|---|---|
abs(x) | Number |
Return the absolute value of x .
|
acos(x) | Number |
Return the arc cosine of x , in radians.
|
atan(x) | Number |
Return the arc tangent of x , in radians.
|
atan2(y,x) | Number |
Return the arc tangent of the quotient y /x , where the signs of y and x are used to determine the quadrant of the result, in radians.
|
ceil(x) | Number |
Return smallest integer which is larger than x (aka "round up").
|
cos(x) | Number |
Return the cosine of x , in radians.
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exp(x) | Number |
Return the value of ex .
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floor(x) | Number |
Return largest integer which is less than x (aka "round down").
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log(x) | Number |
Return the natural logarithm of x .
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max([value1],[value2],[...]) | Number | Return the largest of all arguments supplied. |
min([value1],[value2],[...]) | Number | Return the smallest of all arguments supplied. |
pow(x,y) | Number |
Return the value of raising x to the power y .
|
random() | Number | Return a floating-point random number between 0 (inclusive) and 1 (exclusive). |
round(x) | Number | Round a number to the closest integer. |
sin(x) | Number |
Return the sine of x , in radians.
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sqrt(x) | Number |
Return the square root of x .
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tan(x) | Number |
Return the tangent of x , in radians.
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Instance Properties
name | type | description |
---|---|---|
constructor | Object | A reference to the constructor class for the current object instance. [from Object] |
prototype | Object | The prototype for a class. [from Object] |
Instance Methods
name | returns | description |
---|---|---|
hasOwnProperty(propertyOrMethodName) | Boolean | Determines if the object/instance itself has the named property or method. [from Object] |
isPrototypeOf(instanceToTest) | Boolean | Determines if the calling object prototype is in the inheritance chain for the supplied argument. [from Object] |
propertyIsEnumerable(propertyOrMethodName) | Boolean |
Determines if the object/instance itself has a property or method of the supplied name which will appear in a for (prop in obj) enumeration.
[from Object]
|
toLocaleString() | String |
For most objects, the same as toString() unless explicitly overridden.
[from Object]
|
toString() | String | Returns a string representation of the object. [from Object] |
valueOf() | String |
Returns the internal this value of the object.
[from Object]
|
Constants
name | object | value | description |
---|---|---|---|
E | Math | e | Roughly 2.7182818284590452354. |
LN10 | Math | ln(10) | The natural logarithm of 10, roughly 2.302585092994046 |
LN2 | Math | ln(2) | The natural logarithm of 2, roughly 0.6931471805599453 |
PI | Math | π | Roughly 3.1415926535897932 |
SQRT1_2 | Math | √(0.5) | The square root of 1/2, roughly 0.7071067811865476 |
SQRT2 | Math | √2 | The square root of 2, roughly 1.4142135623730951 |
LOG2E | Math | log2(e) | The base-2 logarithm of e, roughly 1/Math.LN2 or 1.4426950408889634 |
LOG10E | Math | log10(e) | The base-10 logarithm of e, roughly 1/Math.LN10 or 0.4342944819032518 |
Description
The
Math
object is global and non-instantiable. (It is an error to do something like var x = new Math()
.)
Invoke its methods directly as properties of the Class object itself, e.g.:var x = 12.784;
x = Math.round(x);
...instead of the following common mistakes which are invalid:
var x = 12.784;
x.round(); // *** INVALID CODE
round(x); // *** INVALID CODE