Difference between revisions of "Math Module"
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Revision as of 18:03, 9 December 2010
Contents
Math Module
The math module defines extension functions to perform mathematical operations, such as pi
, asin
and acos
. All functions are preceded by the math:
prefix. Some of the functions have also been specified in the
Functions and Operators Specification of the upcoming XQuery 1.1 Recommendation.
math:pi
Signatures 

Summary 
Returns the value of the mathematical constant π. 
Rules 
This function returns the xs:double value whose lexical representation is 3.141592653589793. 
Examples 
The expression 2*math:pi() returns 6.283185307179586e0 .The expression 60 * (math:pi() div 180) converts an angle of 60 degrees to radians. 
math:e
Signatures 

Summary 
Returns the value of the mathematical constant e. 
Rules 
This function returns the xs:double value whose lexical representation is 2.718281828459045. 
Examples 
The expression 5*math:e() returns 13.591409142295225 . 
math:sqrt
Signatures 

Summary 
Returns the square root of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the xs:double value of the mathematical square root of $arg . 
math:sin
Signatures 

Summary 
Returns the sine of the argument, expressed in radians. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the sine of $arg , treated as an angle in radians. 
math:cos
Signatures 

Summary 
Returns the cosine of the argument, expressed in radians. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the cosine of $arg , treated as an angle in radians. 
math:tan
Signatures 

Summary 
Returns the tangent of the argument, expressed in radians. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the tangent of $arg , treated as an angle in radians. 
math:asin
Signatures 

Summary 
Returns the arc sine of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the arc sine of $arg , returned as an angle in radians in the range π/2 to +π/2. 
math:acos
Signatures 

Summary 
Returns the arc cosine of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the arc cosine of $arg , returned as an angle in radians in the range 0 to +π. 
math:atan
Signatures 

Summary 
Returns the arc tangent of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the arc tangent of $arg , returned as an angle in radians in the range π/2 to +π/2. 
math:atan2
Signatures 

Summary 
Returns the arc tangent of the first argument divided by the second argument, the result being in the range π/2 to +π/2 radians. 
Rules 
If $arg1 is the empty sequence, the function returns the empty sequence.Otherwise the result is the arc tangent of $arg1 divided by $arg2 , returned as an angle in radians in the range π to +π. 
math:pow
Signatures 

Summary 
Returns the first argument raised to the power of the second argument. 
Rules 
If $arg1 is the empty sequence, the function returns the empty sequence.Otherwise the result is the $arg1 raised to the power of $arg2 . 
Examples 
The expression math:pow(2, 3) returns 8 . 
math:exp
Signatures 

Summary 
Returns e raised to the power of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the value of e raised to the power of $arg . 
Examples 
The expression math:exp(1) returns e. 
math:log
Signatures 

Summary 
Returns the natural logarithm of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the natural logarithm (base e) of $arg . 
Examples 
The expression math:log(math:e()) returns 1 . 
math:log10
Signatures 

Summary 
Returns the base 10 logarithm of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the base 10 logarithm of $arg . 
Examples 
The expression math:log(100) returns 2 . 
math:random
Signatures 

Summary 
Returns a random value. 
Rules 
This function returns a random xs:double value between 0.0 and 1.0 . 
math:sinh
Signatures 

Summary 
Returns the hyperbolic sine of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the hyperbolic sine of $arg . 
Examples 
The expression math:sinh(0) returns 0 . 
math:cosh
Signatures 

Summary 
Returns the hyperbolic cosine of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the hyperbolic cosine of $arg . 
Examples 
The expression math:cosh(0) returns 1 . 
math:tanh
Signatures 

Summary 
Returns the hyperbolic tangent of the argument. 
Rules 
If $arg is the empty sequence, the function returns the empty sequence.Otherwise the result is the hyperbolic tangent of $arg . 
Examples 
The expression math:tanh(100) returns 1 . 