<?xml version="1.0" encoding="iso-8859-1"?> <?xml-stylesheet href="../make-menu.xsl" type="text/xsl"?><html> <head> <this-is section="expressions" page="comparisons" subpage=""/> <!-- Generated at 2011-12-09T20:47:22.916Z--><title>Saxonica: XSLT and XQuery Processing: Comparisons</title> <meta name="coverage" content="Worldwide"/> <meta name="copyright" content="Copyright Saxonica Ltd"/> <meta name="title" content="Saxonica: XSLT and XQuery Processing: Comparisons"/> <meta name="robots" content="noindex,nofollow"/> <link rel="stylesheet" href="../saxondocs.css" type="text/css"/> </head> <body class="main"> <h1>Comparisons</h1> <p>The simplest comparison operators are <code>eq</code>, <code>ne</code>, <code>lt</code> <code>le</code>, <code>gt</code>, <code>ge</code>. These compare two atomic values of the same type, for example two integers, two dates, or two strings. In the case of strings, the default collation is used (see <a class="bodylink" href="../extensions/instructions/collation.xml">saxon:collation</a>). If the operands are not atomic values, an error is raised.</p> <p>The operators <code>=</code>, <code>!=</code>, <code><</code>, <code><=</code>, <code>></code>, and <code>>=</code> can compare arbitrary sequences. The result is true if any pair of items from the two sequences has the specified relationship, for example <code>$A = $B</code> is true if there is an item in <code>$A</code> that is equal to some item in <code>$B</code>. If an argument is a node, the effect depends on whether the source document has been validated against a schema. In Saxon-EE, with a validated source document, Saxon will use the typed value of the node in the comparison. Without schema validation, the type of the node is <code>untypedAtomic</code>, and the effect is that the value is converted to the type of the other operand.</p> <p>The operator <code>is</code> tests whether the operands represent the same (identical) node. For example, <code>title[1] is *[@note][1]</code> is true if the first <code>title</code> child is the first child element that has a <code>@note</code> attribute. If either operand is an empty sequence the result is an empty sequence (which will usually be treated as false).</p> <p>The operators <code><<</code> and <code>>></code> test whether one node precedes or follows another in document order.</p> <table width="100%"> <tr> <td> <p align="right"><a class="nav" href="instanceof.xml">Next</a></p> </td> </tr> </table> </body> </html>