work on docs

[pspp] / doc / statistics.texi

diff --git a/doc/statistics.texi b/doc/statistics.texi
index 497d3fa5a6351afb280222599ff4e5d85ca94993..60253236545786cc1cebba995a89c2bfee8ff691 100644 (file)
--- a/doc/statistics.texi
+++ b/doc/statistics.texi
@@ -1196,46 +1196,47 @@ The following section lists the available summary functions.
 
 This section lists the summary functions that can be applied to cells
 in @code{CTABLES}.  Many of these functions have an @var{area} in
-their names.  The supported areas are:
-
-@itemize @bullet
-@item
-Areas that correspond to parts of @dfn{sections}, where stacked
-variables divide each section from another:
+their names, indicating that they summarize over multiple cells within
+an area of the output chosen by the user.  The following basic
+@var{area}s are supported, in decreasing order of size:
 
 @table @code
 @item TABLE
-An entire section.
+A @dfn{section}.  Stacked variables divide sections of the output from
+each other.  sections may span multiple layers.
 
 @item LAYER
-A layer within a section.
-
-@item LAYERROW
-A row in one layer within a section.
+A section within a single layer.
 
-@item LAYERCOL
-A column in one layer within a section.
+@item SUBTABLE
+A @dfn{subtable}, whose contents are the cells that pair an innermost
+row variable and an innermost column variable within a single layer.
 @end table
 
-@item
-Areas that correspond to parts of @dfn{subtables}, whose contents are
-the cells that pair an innermost row variable and an innermost column
-variable within a single layer.  A section can contain multiple
-subtables and a subtable is always within a single section:
+The following shows how the output for the table expression @code{qn61
+> qn57 BY qnd7a > qn86 + qn64b BY qns3a}@footnote{This is not
+necessarily a meaningful table, so for clarity variable labels are
+omitted.} is divided up into @code{TABLE}, @code{LAYER}, and
+@code{SUBTABLE} areas.  Each unique value for Table ID is one section,
+and similarly for Layer ID and Subtable ID.  Thus, this output has two
+@code{TABLE} areas (one for @code{qnd7a} and one for @code{qn64b}),
+four @code{LAYER} areas (for those two variables, per layer), and 12
+@code{SUBTABLE} areas.
+@psppoutput {ctables22}
 
-@table @code
-@item ROW
-A row within a subtable.
+@code{CTABLES} also supports the following @var{area}s that further
+divide a subtable or a layer within a section:
 
-@item COL
-A column within a subtable.
+@table @code
+@item LAYERROW
+@itemx LAYERCOL
+A row or column, respectively, in one layer of a section.
 
-@item SUBTABLE
-All the cells in a subtable.
+@item ROW
+@itemx ROW
+A row or column, respectively, in a subtable.
 @end table
 
-@end itemize
-
 The following summary functions may be applied to any variable
 regardless of whether it is categorical or scalar.  The default label
 for each function is listed in parentheses: