How to compare current value with previous or next occurrence?

[TonyMarston]

After sorting my XML data I want to detect when one of the values changes so that I can do something extra, such as insert another line break. I cannot find how to compare an item value with the previous or next occurrence in the structure. Can anyone help me please?

 

[JJR]

There are various ways:

You can use [number] to get an occurance of a specific node
e.g: myxml/mynodes[1]

You can also use the position() function
e.g: myxml/mynodes[position() -1] points to the previous node.

Good luck,

Jordi Reineman

 

[TonyMarston]

I know how to get the number of the previous node, but I am trying to get the value of an item in the previous node so I can compare it with the value of the same item in the current node.

What I am trying to do is step through a sorted list and perform some processing when a value changes between one occurrence and the next.

 

[TonyMarston]

After a lot of trial and error I have managed to find the solution:

1) Create a variable to hold the current value of position()
2) Create a variable to hold the data from an item in the previous/next occurrence
3) Compare the item data in the current occurrence with the contents of variable (2).

Example code looks like this:

<xsl:variable name=&quot;position&quot; select=&quot;position()&quot; />
<xsl:variable name=&quot;next&quot; select=&quot;/UNIFACE/TABLE/OCC[$position+1]/USOURCE:UVAR&quot; />

<xsl:if test=&quot;USOURCE:UVAR != $next&quot;>
    .....
</xsl:if>

If you want the value from the previous occurrence then use [$position-1] instead.