• Chapter 1: Getting Started with Stylus Studio
• Chapter 2: Editing and Querying XML
• Chapter 3: Converting Non-XML Files to XML
• Chapter 4: Working with XSLT
• Chapter 5: Creating XSLT Using the XSLT Mapper
• Chapter 6: Debugging Stylesheets
• Chapter 7: Defining XML Schemas
• Chapter 8: Defining Document Type Definitions
• Chapter 9: Writing XPath Expressions
  • About the XPath Processor
  • Sample Data for Examples and Testing
  • Getting Started with Queries
  • Specifying the Nodes to Evaluate
  • Handling Strings and Text
  • Specifying Boolean Expressions and Functions
  • Specifying Number Operations and Functions
  • Comparing Values
  • Finding a Particular Node
  • Obtaining a Union
  • Obtaining Information About a Node or a Node Set
  • Using XPath Expressions in Stylesheets
  • Accessing Other Documents During Query Execution
  • XPath Quick Reference
• Chapter 10: Working with XQuery in Stylus Studio
• Chapter 11: Composing Web Service Calls
• Chapter 12: Accessing Relational Data as XML
• Chapter 13: Extending Stylus Studio
• Chapter 14: Stylus Studio Reference

Home > Online Product Documentation > Table of Contents > Calling Number Functions

Calling Number Functions

This section describes the number functions that you can call in a query. The operations you can perform are

Converting an Object to a Number

In some situations, you might want to force a numeric comparison. The XPath processor performs a numeric comparison if either operand is numeric and neither is Boolean. (If one operand is Boolean, the XPath processor converts the other to Boolean and performs a Boolean comparison.) However, if neither operand is a numeric or Boolean value, you can call the number() function on one operand to convert it to a numeric value. The XPath processor automatically converts the other operand to a numeric value.

To perform a numeric comparison, you must call the number() function to convert a Boolean operand, if there is one, to a numeric value.

The format of the number() function is

number number(object?) 
               

            

If you omit the argument, the value of the argument defaults to a node set with the context node as its only member. Table 55 shows how the number() function converts its argument to a number:

Obtaining the Sum of the Values in a Node Set

To obtain the sum of the values of the nodes in a set, call the sum() function. The format is

number sum(node-set
              ) 
               

            

For each node in the argument node-set, the XPath processor converts the string value of the node to a number. The sum() function returns the sum of these numbers.

Obtaining the Largest, Smallest, or Closest Number

To obtain the largest integer that is not greater than a particular number, call the floor() function. The format is

number floor(number) 
               

            

The floor() function returns the largest (closest to positive infinity) number that is not greater than the argument and that is an integer. For example:

To obtain the smallest integer that is not less than a particular number, call the ceiling() function. The format is

number ceiling(number) 
               

            

The ceiling() function returns the smallest (closest to negative infinity) number that is not less than the argument and that is an integer. For example:

To obtain the closest integer to a particular number, call the round() function. The format is

number round(number) 
               

            

The round() function returns the number that is closest to the argument and that is an integer. If there are two such numbers, the function returns the one that is closest to positive infinity. For example: