1 @c PSPP - a program for statistical analysis.
2 @c Copyright (C) 2019 Free Software Foundation, Inc.
3 @c Permission is granted to copy, distribute and/or modify this document
4 @c under the terms of the GNU Free Documentation License, Version 1.3
5 @c or any later version published by the Free Software Foundation;
6 @c with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
7 @c A copy of the license is included in the section entitled "GNU
8 @c Free Documentation License".
12 @chapter Processing Data
29 *** Casereaders generalities
30 *** Casereaders from data files
31 *** Casereaders from the active dataset
34 *** Casewriters generally
35 *** Casewriters to data files
36 *** Modifying the active dataset
37 **** Modifying cases obtained from active dataset casereaders has no real effect
38 **** Transformations; procedures that transform
40 *** Sorting and merging
43 **** Ordering and interaction of filtering and grouping
44 *** Multiple passes over data
45 *** Counting cases and case weights
47 *** Multiple passes with filters versus single pass with loops
48 *** Sequential versus random access
50 *** Passing cases around
51 *** Renaming casereaders
52 *** Avoiding excessive buffering
53 *** Propagating errors
54 *** Avoid static/global data
55 *** Don't worry about null filters, groups, etc.
56 *** Be aware of reference counting semantics for cases