cleanup

[pspp] / doc / combining.texi

diff --git a/doc/combining.texi b/doc/combining.texi
index 3b4eb902e049eeae669752b7a5cd2c6299d70b96..a237c1a5bded14506120ad10b18df53e6a686bf8 100644 (file)
--- a/doc/combining.texi
+++ b/doc/combining.texi
@@ -1,3 +1,12 @@
+@c PSPP - a program for statistical analysis.
+@c Copyright (C) 2017, 2020 Free Software Foundation, Inc.
+@c Permission is granted to copy, distribute and/or modify this document
+@c under the terms of the GNU Free Documentation License, Version 1.3
+@c or any later version published by the Free Software Foundation;
+@c with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts.
+@c A copy of the license is included in the section entitled "GNU
+@c Free Documentation License".
+@c

 @node Combining Data Files
 @chapter Combining Data Files
 
 @node Combining Data Files
 @chapter Combining Data Files
 


@@ -58,9 +67,11 @@ This section describes the syntactical features in common among the
 @cmd{ADD FILES}, @cmd{MATCH FILES}, and @cmd{UPDATE} commands.  The
 following sections describe details specific to each command.
 
 @cmd{ADD FILES}, @cmd{MATCH FILES}, and @cmd{UPDATE} commands.  The
 following sections describe details specific to each command.
 

-Each of these commands reads two or more input files and combines
-them.  The command's output becomes the new active dataset.  The input
-files are not changed on disk.
+Each of these commands reads two or more input files and combines them.
+The command's output becomes the new active dataset.
+None of the commands actually change the input files.
+Therefore, if you want the changes to become permanent, you must explicitly
+save them using an appropriate procedure or transformation (@pxref{System and Portable File IO}).

 
 The syntax of each command begins with a specification of the files to
 be read as input.  For each input file, specify FILE with a system
 
 The syntax of each command begins with a specification of the files to
 be read as input.  For each input file, specify FILE with a system


@@ -77,7 +88,7 @@ Each @subcmd{FILE} subcommand may be followed by any number of @subcmd{RENAME}
 subcommands that specify a parenthesized group or groups of variable
 names as they appear in the input file, followed by those variables'
 new names, separated by an equals sign (@subcmd{=}),
 subcommands that specify a parenthesized group or groups of variable
 names as they appear in the input file, followed by those variables'
 new names, separated by an equals sign (@subcmd{=}),

-e.g. @subcmd{/RENAME=(OLD1=NEW1)(OLD2=NEW2)}.  To rename a single
+@i{e.g.} @subcmd{/RENAME=(OLD1=NEW1)(OLD2=NEW2)}.  To rename a single

 variable, the parentheses may be omitted: @subcmd{/RENAME=@var{old}=@var{new}}.
 Within a parenthesized group, variables are renamed simultaneously, so
 that @subcmd{/RENAME=(@var{A} @var{B}=@var{B} @var{A})} exchanges the
 variable, the parentheses may be omitted: @subcmd{/RENAME=@var{old}=@var{new}}.
 Within a parenthesized group, variables are renamed simultaneously, so
 that @subcmd{/RENAME=(@var{A} @var{B}=@var{B} @var{A})} exchanges the


@@ -168,6 +179,9 @@ only in files that are not present for the current case are set to the
 system-missing value for numeric variables or spaces for string
 variables.
 
 system-missing value for numeric variables or spaces for string
 variables.
 

+These commands may combine any number of files, limited only by the
+machine's memory.
+

 @node ADD FILES
 @section ADD FILES
 @vindex ADD FILES
 @node ADD FILES
 @section ADD FILES
 @vindex ADD FILES


@@ -296,7 +310,7 @@ Once per command:
 @end display
 
 @cmd{UPDATE} updates a @dfn{master file} by applying modifications
 @end display
 
 @cmd{UPDATE} updates a @dfn{master file} by applying modifications

-from one or more @dfn{transaction files}.  
+from one or more @dfn{transaction files}.

 
 @cmd{UPDATE} shares the bulk of its syntax with other @pspp{} commands for
 combining multiple data files.  @xref{Combining Files Common Syntax},
 
 @cmd{UPDATE} shares the bulk of its syntax with other @pspp{} commands for
 combining multiple data files.  @xref{Combining Files Common Syntax},


@@ -315,14 +329,14 @@ case in the master file:
 @itemize @bullet
 @item
 When a match is found, then the values of the variables present in the
 @itemize @bullet
 @item
 When a match is found, then the values of the variables present in the

-transaction file replace those variable's values in the new active
+transaction file replace those variables' values in the new active

 file.  If there are matching cases in more than more transaction file,
 @pspp{} applies the replacements from the first transaction file, then
 from the second transaction file, and so on.  Similarly, if a single
 transaction file has cases with duplicate @subcmd{BY} values, then those are
 applied in order to the master file.
 
 file.  If there are matching cases in more than more transaction file,
 @pspp{} applies the replacements from the first transaction file, then
 from the second transaction file, and so on.  Similarly, if a single
 transaction file has cases with duplicate @subcmd{BY} values, then those are
 applied in order to the master file.
 

-When a variable in a transaction file has a missing value or a string
+When a variable in a transaction file has a missing value or when a string

 variable's value is all blanks, that value is never used to update the
 master file.
 
 variable's value is all blanks, that value is never used to update the
 master file.