ms:number Function
Takes a string argument in XSD format and converts it into an XPath number.
number ms:number(string)
Remarks
The ms:number() function performs conversion the same way as the native XPath number() function, with the exceptions that the ms:number() function converts "-INF" and "INF" into minus and plus infinity, and mathematical notation such as (1.2e-3) into numbers, not NaNs. For a complete set of numeric formats that can be processed, see the XSD Specification. If the ms:number() function is unable to convert a string, it returns a NaN.