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ERXArrayUtilities provides convenience methods and tools for manipulating NSArrays. Many of the methods are self explanatory. For a full list please see the api (http://webobjects.mdimension.comwocommunity.org/documents/javadoc/wonder/apilatester/erextensions/extensionsfoundation/ERXArrayUtilities.html).
NSArray operators
WebObjects provides @sum, @avg, etc array operators. ERXArrayUtilities adds quite a few more:
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