OpenMusic Reference
range-filter
range-filter
(lists module) -- Filters elements of a tree based on their ordinal position
Syntax
range-filter list posn mode
Inputs
| name | data type(s) | comments |
|---|---|---|
| list | a tree | the tree to filter |
| posn | a list of pairs ofnumbers | must contain at least one pair of numbers, for example ((1 3)) |
| mode | menu | two options: pass and reject. Defaults to ‘reject’ |
Output
| output | data type(s) | comments |
|---|---|---|
| first | a tree |
Description
range-filter passes or rejects all elements from list that fall within the range of positions specified in posn . Multiple ranges of positions can be specified in the form of additional pairs of numbers as sublists of posn . Even if there is only one range, it must be given as a sublist of posn , which must thus have two levels of parentheses. Each pair of numbers defines a range of positions, counting from zero (as usual).
If mode is set to pass , only elements within one of these ranges are passed. If mode is set to reject , elements falling within any one of these intervals are suppressed.
 |
If you are looking to filter ranges of elements in a list based on their numerical value rather than their position in the list, use band- filter
—|—
Examples
Filtering a range of positions from a list
Mode is set to pass , so only the elements in between positions 0-1 and 4-5, inclusive, will be passed. Sublists are treated as single elements:
? OM->((1 (2 3) (a b) 8)
Reversing the mode will cause only elements outside of those intervals to be passed, namely, positions 2 and 3:
? OM->(5 7)
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