## org.apache.poi.ss.formula.functions
Class Lookup

    java.lang.Object
      org.apache.poi.ss.formula.functions.Lookup

All Implemented Interfaces:
  Function, Function2Arg, Function3Arg

    public final class Lookup

extends java.lang.Object

Implementation of Excel function LOOKUP.

LOOKUP finds an index row in a lookup table by the first column value and returns the value from another column. Syntax:
VLOOKUP(lookup_value, lookup_vector, result_vector)

lookup_value The value to be found in the lookup vector.
lookup_vector An area reference for the lookup data.
result_vector Single row or single column area reference from which the result value is chosen.

Author:
  Josh Micich

Constructor Summary
`Lookup()`

Method Summary
`ValueEval` `evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0, ValueEval arg1)` see `Function.evaluate(ValueEval[], int, int)`
`ValueEval` `evaluate(int srcRowIndex, int srcColumnIndex, ValueEval arg0, ValueEval arg1, ValueEval arg2)` see `Function.evaluate(ValueEval[], int, int)`
`ValueEval` `evaluate(ValueEval[] args, int srcRowIndex, int srcColumnIndex)`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Constructor Detail

### Lookup

    public Lookup()

Method Detail

### evaluate

    public ValueEval evaluate(int srcRowIndex,
                              int srcColumnIndex,
                              ValueEval arg0,
                              ValueEval arg1)

  Description copied from interface: `Function2Arg`
  see `Function.evaluate(ValueEval[], int, int)`

### evaluate

    public ValueEval evaluate(int srcRowIndex,
                              int srcColumnIndex,
                              ValueEval arg0,
                              ValueEval arg1,
                              ValueEval arg2)

  Description copied from interface: `Function3Arg`
  see `Function.evaluate(ValueEval[], int, int)`

### evaluate

    public final ValueEval evaluate(ValueEval[] args,
                                    int srcRowIndex,
                                    int srcColumnIndex)

  Specified by:
    `evaluate` in interface `Function`
  Parameters:
    `args` - the evaluated function arguments. Empty values are represented with `BlankEval` or `MissingArgEval`, never `null`.
    `srcRowIndex` - row index of the cell containing the formula under evaluation
    `srcColumnIndex` - column index of the cell containing the formula under evaluation
  Returns:
    The evaluated result, possibly an `ErrorEval`, never `null`. Note - Excel uses the error code #NUM! instead of IEEE NaN, so when numeric functions evaluate to `Double.NaN` be sure to translate the result to `ErrorEval.NUM_ERROR`.

Copyright 2012 The Apache Software Foundation or its licensors, as applicable.