The Number menu contains the following functions:
Number: Converts the argument to a number. For detailed information about the logic, see the XPath 1.0 specification.
Number Literal: Specifies a number literal.
Round: Returns the number that is closest to the argument and that is an integer.
Sum: Returns the sum, for each node in the argument node-set, of the result of converting the string values of the node to a number.
Floor: Returns the largest number that is not greater than the argument and that is an integer.
Ceiling: Returns the smallest number that is not less than the argument and that is an integer.