• 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
    • About Comparison Operators
    • How the XPath Processor Evaluates Comparisons
    • Comparing Node Sets
    • Comparing Single Values With = and !=
    • Comparing Single Values With <=, <, >, and >=
    • Priority of Object Types in Comparisons
    • Examples of Comparisons
    • Operating on Boolean 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: Integrating with Third-Party File Systems
• Chapter 14: Extending Stylus Studio
• Chapter 15: Stylus Studio GUI Reference

Home > Online Product Documentation > Table of Contents > Comparing Single Values With = and !=

Comparing Single Values With = and !=

When neither object to be compared is a node set and the operator is = or !=, the XPath processor compares the objects by converting them to a common type and then comparing them. The XPath processor converts the objects to a common type as follows:

If the objects to be compared are neither Boolean nor numeric, the XPath processor compares the string values of the objects as if by applying the string() function to each object.

The = comparison returns true if and only if the objects are equal. The != comparison returns true if and only if the objects are not equal. Numbers are compared for equality according to IEEE 754. Two Boolean values are equal if either both are true or both are false. Two strings are equal if and only if they both consist of the same sequence of Universal Character Set (UCS) characters.