Script Library: 1223 scripts
 

sort-series.r

Rebol [ Library: [ level: 'intermediate platform: 'all type: 'function domain: 'database tested-under: ["REBOL/View 1.2.1.3.1 21-Jun-2001" "REBOL/View 1.3.1.3.1 17-Jun-2005 Core 2.6.0"] support: none license: 'pd see-also: none ] Title: "sort-series-of-elements" Date: 06-Nov-2005 File: %sort-series.r Purpose: {Sorting a series of items. Specify how many fields per record, which field to sort on, and Ascending or Descending order.} Version: 1.0.0 Author: "Gordon Raboud with some help from Volker, DideC, Sunanda and BrianH" ] { The verbose version - I like comments } sort-series-of-elements: func [ "Sort a series of non-blocked items" Series [block!] "Continuous sequential series of items" Elements [integer!] "Number of items per record" SortField [integer!] "Order the records based on this field" SortOrder [char!] "Must be 'a' or 'A' for ascending or 'd' or 'D' for descending" ] [ BlockSeries: copy [] {The array by complete RECORDS} SortedSeries: copy [] {The array by a long series of individual items} forskip Series Elements [append/only BlockSeries copy/part Series Elements] { The above "foreach" loop converts the series of individual items into an array of record blocks.} Switch SortOrder [ #"a" [sort-method: func [a b] [(at a SortField) < (at b SortField)]] #"d" [sort-method: func [a b] [(at a SortField) > (at b SortField)]] ] foreach Record sort/compare BlockSeries :sort-method [append SortedSeries Record] {The above "foreach" loop does the following: 1. Sorts the array "BlockSeries" by looking at the "SortField" element of each record and then comparing to see if [A < B] or [A >B] according to SortOrder. 2. Then it reduces the array from blocks of records to individual elements and stores those elements into the array "SortedSeries".} return SortedSeries ] { The same function with comments and help removed; just in case a year from now you don't want to know how it works. ;) } sort-series-of-elements: func [ Series [block!] Elements [integer!] SortField [integer!] SortOrder [char!] ] [ BlockSeries: copy [] SortedSeries: copy [] forskip Series Elements [append/only BlockSeries copy/part Series Elements] Switch SortOrder [ #"a" [sort-method: func [a b] [(at a SortField) < (at b SortField)]] #"d" [sort-method: func [a b] [(at a SortField) > (at b SortField)]] ] foreach Record sort/compare BlockSeries :sort-method [append SortedSeries Record] return SortedSeries ] { Example code on how to use} UnSortedSeries: read %"DataToSort2.csv" {try exporting a DB from a spreadsheet} DistinctItems: parse/all Unsortedseries "," FieldsPerRecord: 9 SortOnFieldNumber: 4 SortOrder: #"d" Header: copy/part DistinctItems FieldsPerRecord DistinctItems: skip DistinctItems FieldsPerRecord {Strip header from data to be sorted} sort-series-of-elements DistinctItems FieldsPerRecord SortOnFieldNumber SortOrder { Show results of sort } Print Header forskip SortedSeries FieldsPerRecord [ print [copy/part SortedSeries FieldsPerRecord] ] halt {so you can see the results }
halt ;; to terminate script if DO'ne from webpage