Power in sparql and other math functions

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+1 Q:

Power in sparql and other math functions

I am trying to write a sparql query where I want to filter on the square of something, but I am simply unable to figure out how to square a number (x^2) (except by multiplying it with itself of cause.) I guessed a square root function called math:sqrt() which works, yet nothing like math:pow seems to exist.

How do I get the square of something in sparql, and more interesting where can I read about it and other math functions such as math:sqrt in sparql?

+1 A:

SPARQL supports some XPath arithmetic functions such as + - * /. They are described in the SPARQL spec.

The power function is not supported by the spec. And in any case x*x is more efficient way to compute squares than pow(x,2) would be.

laalto 2009-09-10 10:07:43

Hi. Thanks. What about specification of other math functions, such as the square root (math:sqrt seems to work fine) and the trigonometric functions sin, and cos? I updated the question a bit.

bjarkef 2009-09-10 11:25:55

Those would be implementation-specific extensions, not part of the core SPARQL.

laalto 2009-09-11 08:46:14

Where would I find documentation on these implementation-specific extensions?

bjarkef 2009-09-12 08:48:00

Well, start with your SPARQL query engine documentation. I cannot read your mind and don't know which one you are using.

laalto 2009-09-13 11:50:37

ansaurus

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Power in sparql and other math functions

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