Home
JavaScript and XPages reference
This reference describes the JavaScript™ language elements, Application Programming Interfaces (APIs), and other artifacts that you need to create scripts, plus the XPages simple actions.
Standard (JavaScript)
The Standard library contains classes for manipulating data of different types and performing common operations.
Math (JavaScript)
Represents common mathematical values and functions.
acos (JavaScript)
Gets the inverse cosine of an angle.

JavaScript and XPages reference
This reference describes the JavaScript™ language elements, Application Programming Interfaces (APIs), and other artifacts that you need to create scripts, plus the XPages simple actions.
- JavaScript™ language elements (JavaScript)
  The JavaScript™ language elements are based on the ECMAScript Language Specification Standard ECMA-262 (see http://www.ecma-international.org/publications/standards/Ecma-262.htm). The JavaScript described here applies to the server-side interpreter. Client-side scripts are interpreted by the browser.
- Simple actions (JavaScript)
  A simple action performs a pre-programmed activity that can be modified by arguments.
- Global objects and functions (JavaScript™)
  Global objects provide entry points to server-side scripts. Entering the name of a global object instantiates it.
- DOM (JavaScript)
  Represents a document in XML Document Object Model format.
- Domino®
  This library provides access to the IBM® Domino® back-end.
- Runtime (JavaScript)
  The Runtime library contains classes that provide useful methods for globalization.
- Standard (JavaScript)
  The Standard library contains classes for manipulating data of different types and performing common operations.
  - Array (Standard - JavaScript)
    Represents an array.
  - Boolean (Standard - JavaScript)
    Represents a boolean value.
  - Date (Standard - JavaScript)
    Represents a date and time.
  - Math (JavaScript)
    Represents common mathematical values and functions.
    - abs (JavaScript)
      Gets the absolute value of a number.
    - acos (JavaScript)
      Gets the inverse cosine of an angle.
    - asin (JavaScript)
      Gets the inverse sine of an angle.
    - atan (JavaScript)
      Gets the inverse tangent of an angle.
    - atan2 (JavaScript)
      Gets the inverse tangent of an angle using two parameters.
    - ceil (JavaScript)
      Rounds a number to an integer by truncating the fraction and adding 1.
    - cos (JavaScript)
      Gets the cosine of an angle.
    - deg (JavaScript)
      Converts radians to degrees.
    - exp (JavaScript)
      Gets an exponential power of e.
    - floor (JavaScript)
      Rounds a number to an integer by truncating the fraction.
    - IEEEremainder (JavaScript)
      Gets the remainder of a division according to IEEE 754.
    - log (JavaScript)
      Gets the natural logarithm (base e) of a number.
    - max (JavaScript)
      Gets the greater of two numbers.
    - min (JavaScript)
      Gets the lesser of two numbers.
    - pow (JavaScript)
      Gets a number raised to the exponential power of another number.
    - rad (JavaScript)
      Converts degrees to radians.
    - random (JavaScript)
      Generates a pseudorandom number greater than or equal to 0.0 and less than 1.0.
    - rint (JavaScript)
      Rounds a number to the nearest integer, with 0.5 rounded to the even integer.
    - round (JavaScript)
      Rounds a number to the nearest integer.
    - sin (JavaScript)
      Gets the sine of an angle.
    - sqrt (JavaScript)
      Gets the positive square root of a number.
    - tan (JavaScript)
      Gets the tangent of an angle.
    - toDegrees (JavaScript)
      Converts radians to degrees.
    - toRadians (JavaScript)
      Converts degrees to radians.
    - E (JavaScript)
      The value of e.
    - LN10 (JavaScript)
      Value of the natural logarithm of 10.
    - LN2 (JavaScript)
      Value of the natural logarithm of 2.
    - LOG10E (JavaScript)
      Value of the logarithm of e to the base 10.
    - LOG2E (JavaScript)
      Value of the logarithm of e to the base 2.
    - PI (JavaScript)
      The value of pi.
    - SQRT1_2 (JavaScript)
      The value of the square root of 1/2.
    - SQRT2 (JavaScript)
      The value of the square root of 2.
  - Number (Standard - JavaScript)
    Represents a numeric value.
  - Object (JavaScript)
    Provides common methods for all classes.
  - RegExp (Standard - JavaScript)
  - String (Standard - JavaScript)
    Represents a string.
- XSP (JavaScript™)
  The XSP library contains classes that access the browser context.

acos (JavaScript)

Gets the inverse cosine of an angle.

Defined in

Syntax

acos(value:double)
: double


Parameter	Description
`value`	The cosine of an angle; that is, the ratio of the opposite side to the hypotenuse. See below for special cases.


Return value	Description
`double`	The inverse cosine of the parameter in radians. See rad (JavaScript) to convert degrees to radians.

Usage

Special cases are as follows:

The inverse cosine of NaN or an absolute value greater than 1 is NaN.

Examples

This button onclick event calculates an angle in degrees of a right triangle given the length of the opposite side and the length of the hypotenuse.

sessionScope.angleA = 
	Math.deg(Math.acos(sessionScope.b / sessionScope.h))