ValuesGreaterThan ( listvalues ; reference )

Returns all values in a list that are greater than the reference; it is referenced by QuickSort ( listvalues ).

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Theo Gantos
TEKA, Inc.
http://www.tekainc.com

Sample input:

ValuesGreaterThan ( "A
B
1
2
3
" , 2 )

Sample output:

3
A
B

Function definition: (Copy & paste into FileMaker's Edit Custom Function window)

/*
ValuesGreaterThan( listvalues; reference)
Theo Gantos - TEKA, Inc. - www.tekainc.com
Returns all values in list that are greater than the reference parameter
Originally written by Jeremy Bante, OshVay Systems, Inc., but was lost, so I rewrote it
Original function used the parameter List, which is now a reserved word, changed to listvalues.
Used by QuickSort(listvalues), also written by Jeremy
*/

Let(
  listLength = ValueCount( listvalues );

  Case(
      //if the first element is greater than the reference...
    LeftValues( listvalues; 1) > reference;
      //return the first element
    LeftValues( listvalues; 1)
  )

  &

  Case(
      //if list is not trivial [there's more than one element]
    listLength > 1;
      //return all other elements greater than reference
    ValuesGreaterThan(
      RightValues( listvalues; listLength - 1);
      reference
    )
  )
)  //end Let()

ValuesGreaterThan( listvalues; reference) returns a list of all values in list that are greater than the reference by comparing the first value; then prepending all other values greater than the reference with a recursive call to itself.

ValuesGreaterThan(listvalues; reference) is used by QuickSort( listvalues) to separate out values that are greater than a particular "pivot" value.

Originally written by Jeremy Bante, but it was lost, so I re-wrote it to make QuickSort(listvalues) work properly. Now there is no reason to EVER use the atrocious BubbleSort again!

I hope everyone enjoys it.

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Note: these functions are not guaranteed or supported by BrianDunning.com. Please contact the individual developer with any questions or problems.

ValuesGreaterThan ( listvalues ; reference )

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