moved knowledge of pspp_linreg_cache out of pspp_coeff_init

[pspp-builds.git] / doc / transformation.texi

diff --git a/doc/transformation.texi b/doc/transformation.texi
index 0050f9989fc27631880cd93de06e405cb5054255..327f67391210f640b810dc798d284cb2fa522e64 100644 (file)
--- a/doc/transformation.texi
+++ b/doc/transformation.texi
@@ -23,7 +23,7 @@ as a rule.
 
 @display
 AGGREGATE 
 
 @display
 AGGREGATE 

-        OUTFILE=@{*,'filename'@}          
+        OUTFILE=@{*,'file-name',file_handle@}

         /PRESORTED
         /DOCUMENT
         /MISSING=COLUMNWISE
         /PRESORTED
         /DOCUMENT
         /MISSING=COLUMNWISE


@@ -37,9 +37,11 @@ variables called @dfn{break variables}.  Several functions are available
 for summarizing case contents.
 
 The OUTFILE subcommand is required and must appear first.  Specify a
 for summarizing case contents.
 
 The OUTFILE subcommand is required and must appear first.  Specify a

-system file by file name string or file handle (@pxref{FILE HANDLE}).
+system file, portable file, or scratch file by file name or file
+handle (@pxref{File Handles}).

 The aggregated cases are written to this file.  If @samp{*} is
 The aggregated cases are written to this file.  If @samp{*} is

-specified, then the aggregated cases replace the active file.
+specified, then the aggregated cases replace the active file.  Use of
+OUTFILE to write a portable file or scratch file is a PSPP extension.

 
 By default, the active file will be sorted based on the break variables
 before aggregation takes place.  If the active file is already sorted
 
 By default, the active file will be sorted based on the break variables
 before aggregation takes place.  If the active file is already sorted


@@ -103,6 +105,9 @@ format is F5.3.
 @item FIRST(var_name)
 First non-missing value in break group.  The aggregation variable
 receives the complete dictionary information from the source variable.
 @item FIRST(var_name)
 First non-missing value in break group.  The aggregation variable
 receives the complete dictionary information from the source variable.

+The sort performed by AGGREGATE (and by SORT CASES) is stable, so that
+the first case with particular values for the break variables before
+sorting will also be the first case in that break group after sorting.

 
 @item FOUT(var_name, low, high)
 Fraction of values strictly outside the specified range of constants.
 
 @item FOUT(var_name, low, high)
 Fraction of values strictly outside the specified range of constants.


@@ -111,6 +116,9 @@ The default format is F5.3.
 @item LAST(var_name)
 Last non-missing value in break group.  The aggregation variable
 receives the complete dictionary information from the source variable.
 @item LAST(var_name)
 Last non-missing value in break group.  The aggregation variable
 receives the complete dictionary information from the source variable.

+The sort performed by AGGREGATE (and by SORT CASES) is stable, so that
+the last case with particular values for the break variables before
+sorting will also be the last case in that break group after sorting.

 
 @item MAX(var_name)
 Maximum value.  The aggregation variable receives the complete
 
 @item MAX(var_name)
 Maximum value.  The aggregation variable receives the complete


@@ -380,7 +388,8 @@ specified are discarded.  If the VARIABLES subcommand is omitted, all
 variables are selected for transposition.
 
 The variables specified by NEWNAMES, which must be a string variable, is
 variables are selected for transposition.
 
 The variables specified by NEWNAMES, which must be a string variable, is

-used to give names to the variables created by @cmd{FLIP}.  If
+used to give names to the variables created by @cmd{FLIP}.  Only the
+first 8 characters of the variable are used.  If

 NEWNAMES is not
 specified then the default is a variable named CASE_LBL, if it exists.
 If it does not then the variables created by FLIP are named VAR000
 NEWNAMES is not
 specified then the default is a variable named CASE_LBL, if it exists.
 If it does not then the variables created by FLIP are named VAR000


@@ -394,11 +403,12 @@ extensions are added, starting with 1, until a unique name is found or
 there are no remaining possibilities.  If the latter occurs then the
 FLIP operation aborts.
 
 there are no remaining possibilities.  If the latter occurs then the
 FLIP operation aborts.
 

-The resultant dictionary contains a CASE_LBL variable, which stores the
-names of the variables in the dictionary before the transposition.  If
-the active file is subsequently transposed using @cmd{FLIP}, this
-variable can
-be used to recreate the original variable names.
+The resultant dictionary contains a CASE_LBL variable, a string
+variable of width 8, which stores the names of the variables in the
+dictionary before the transposition.  Variables names longer than 8
+characters are truncated.  If the active file is subsequently
+transposed using @cmd{FLIP}, this variable can be used to recreate the
+original variable names.

 
 FLIP honors @cmd{N OF CASES} (@pxref{N OF CASES}).  It ignores
 @cmd{TEMPORARY} (@pxref{TEMPORARY}), so that ``temporary''
 
 FLIP honors @cmd{N OF CASES} (@pxref{N OF CASES}).  It ignores
 @cmd{TEMPORARY} (@pxref{TEMPORARY}), so that ``temporary''


@@ -527,11 +537,17 @@ are sorted in ascending order.  To override sort order, specify (D) or
 for ascending order.  These apply to the entire list of variables
 preceding them.
 
 for ascending order.  These apply to the entire list of variables
 preceding them.
 

+The sort algorithms used by @cmd{SORT CASES} are stable.  That is,
+records that have equal values of the sort variables will have the
+same relative order before and after sorting.  As a special case,
+re-sorting an already sorted file will not affect the ordering of
+cases.
+

 @cmd{SORT CASES} is a procedure.  It causes the data to be read.
 
 @cmd{SORT CASES} attempts to sort the entire active file in main memory.
 @cmd{SORT CASES} is a procedure.  It causes the data to be read.
 
 @cmd{SORT CASES} attempts to sort the entire active file in main memory.

-If main memory is exhausted, it falls back to a merge sort algorithm that
-involves writing and reading numerous temporary files.
+If workspace is exhausted, it falls back to a merge sort algorithm that
+involves creates numerous temporary files.

 
 @cmd{SORT CASES} may not be specified following TEMPORARY.  
 @setfilename ignored
 
 @cmd{SORT CASES} may not be specified following TEMPORARY.  
 @setfilename ignored