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ΔLIST
Synopsis
Return first differences of elements of a list
Description
The ΔLIST command returns the first differences of the elements in the list Ldata, i.e. $ data_2-data_1 $, $ data_3-data_2 $ and so on.
The list must contain at least two elements, and the elements themselves must be suitable for subtraction.
Compatibility
ΔLIST is fully equivalent to its userRPL counterpart.
Usage
Input
4:
3:
2:
1: { 39 18 5 '2*X' 73 }
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ΔLIST
Output
4:
3:
2:
1: { -21 -13 '2*X-5' '73-2*X' }
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Related Commands
| Command | Short Description | |
|---|---|---|
| →LIST | Assemble a list from its elements | |
| LIST→ | Split a list into its elements | |
| DOLIST | Do a procedure with elements of lists | CHANGED |
| DOSUBS | Do a procedure on a subset of a list | CHANGED |
| MAP | Do a procedure on each element of a list, recursively | |
| MAPLIST→ | Do a procedure on each element recursively, return individual elements | NEW |
| STREAM | Do a procedure on consecutive elements of a list | |
| ΔLIST | First differences on the elements of a list | |
| ΣLIST | Sum of all elements in a list | CHANGED |
| ΠLIST | Product of all elements in a list | CHANGED |
| ADD | Concatenate lists and/or elements | CHANGED |
| SORT | Sort elements in a list | |
| REVLIST | Reverse the order of elements in a list | |
| ADDROT | Add elements to a list, keep only the last N elements | NEW |
| SEQ | Assemble a list from results of sequential procedure |