Basic Examples (2) 

ValueMapIndexed with a symbolic function f applied to a list of strings:

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Creates an association where each key is a hash of a value from a given list and the position of that value in the list:

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Scope (2) 

ValueMapIndexed works on the first level of expressions:

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It can be made to work on lower levels by using Map in conjunction with ValueMapIndexed:

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ValueMapIndexed works with Query on datasets:

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It also works with implicit Query operations:

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Applications (1) 

Create integer row headers for the Paul Revere social network:

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Properties and Relations (1) 

The resource function ValueMap is a special case of ValueMapIndexed, in which one ignores the index argument:

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Possible Issues (2) 

If a key generated from application of the function is not unique, the value for that key will be the last value encountered that generated the key:

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ValueMapIndexed will not work properly on datasets without the use of Query:

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Neat Examples (1) 

Use ValueMapIndexed to create a custom index on the hash of a function of two columns of a dataset and then use the index to swiftly retrieve information:

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