# XQuery and XPath Functions and Operators Math Namespace Document

## 2 XQuery and XPath Math Functions

The normative definitions of these functions are in the [XPath and XQuery Functions and Operators 3.0] specification. For convenience, a very brief, non-normative summary of each function is provided. For details, follow the link on the “Summary:” introductory text below each function.

### acos

Returns the arc cosine of the argument, the result being in the range zero to +π radians.

### asin

Returns the arc sine of the argument, the result being in the range -π/2 to +π/2 radians.

### atan

Returns the arc tangent of the argument, the result being in the range -π/2 to +π/2 radians.

### atan2

Returns the angle in radians subtended at the origin by the point on a plane with coordinates (x, y) and the positive x-axis, the result being in the range -π to +π.

### cos

Returns the cosine of the argument, expressed in radians.

### exp

Returns the value of ex.

### exp10

Returns the value of `10`x.

### log

Returns the natural logarithm of the argument.

### log10

Returns the base-ten logarithm of the argument.

### pi

Returns an approximation to the mathematical constant π.

### pow

Returns the result of raising the first argument to the power of the second.

### sin

Returns the sine of the argument, expressed in radians.

### sqrt

Returns the non-negative square root of the argument.

### tan

Returns the tangent of the argument, expressed in radians.

## 3 Normative References

These documents describe the names that are defined in this namespace at the time of publication. The W3C reserves the right to define additional names in this namespace in the future.

XPath and XQuery Functions and Operators 3.0

XPath and XQuery Functions and Operators 3.0 (Working Draft of 14 December 2010)

## 4 Non-Normative References

Resource Directory Description Language (RDDL)
Gleaning Resource Descriptions from Dialects of Languages (GRDDL)
Resource Description Framework (RDF): Concepts and Abstract Syntax