+@c PSPP - a program for statistical analysis.
+@c Copyright (C) 2017 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 System and Portable File IO
@chapter System and Portable File I/O
* GET DATA:: Read from foreign files.
* IMPORT:: Read from a portable file.
* SAVE:: Write to a system file.
+* SAVE DATA COLLECTION:: Write to a system file and metadata file.
* SAVE TRANSLATE:: Write data in foreign file formats.
* SYSFILE INFO:: Display system file dictionary.
* XEXPORT:: Write to a portable file, as a transformation.
@cmd{GET} clears the current dictionary and active dataset and
replaces them with the dictionary and data from a specified file.
-The @subcmd{FILE} subcommand is the only required subcommand.
-Specify the system
-file or portable file to be read as a string file name or
-a file handle (@pxref{File Handles}).
+The @subcmd{FILE} subcommand is the only required subcommand. Specify
+the SPSS system file, SPSS/PC+ system file, or SPSS portable file to
+be read as a string file name or a file handle (@pxref{File Handles}).
By default, all the variables in a file are read. The DROP
subcommand can be used to specify a list of variables that are not to be
file on disk. Only the active dataset read from the file
is affected by these subcommands.
-@pspp{} tries to automatically detect the encoding of string data in the
-file. Sometimes, however, this does not work well encoding,
-especially for files written by old versions of SPSS or @pspp{}. Specify
-the @subcmd{ENCODING} subcommand with an @acronym{IANA} character set name as its string
-argument to override the default. The @subcmd{ENCODING} subcommand is a @pspp{}
-extension.
+@pspp{} automatically detects the encoding of string data in the file,
+when possible. The character encoding of old SPSS system files cannot
+always be guessed correctly, and SPSS/PC+ system files do not include
+any indication of their encoding. Specify the @subcmd{ENCODING}
+subcommand with an @acronym{IANA} character set name as its string
+argument to override the default. Use @cmd{SYSFILE INFO} to analyze
+the encodings that might be valid for a system file. The
+@subcmd{ENCODING} subcommand is a @pspp{} extension.
@cmd{GET} does not cause the data to be read, only the dictionary. The data
is read later, when a procedure is executed.
Spreadsheet files created by Gnumeric (@url{http://gnumeric.org}).
@item ODS
-Spreadsheet files in OpenDocument format.
+Spreadsheet files in OpenDocument format (@url{http://opendocumentformat.org}).
@item PSQL
Relations from PostgreSQL databases (@url{http://postgresql.org}).
/SHEET=@{NAME '@var{sheet_name}', INDEX @var{n}@}
/CELLRANGE=@{RANGE '@var{range}', FULL@}
/READNAMES=@{ON, OFF@}
- /ASSUMEDVARWIDTH=@var{n}.
+ /ASSUMEDSTRWIDTH=@var{n}.
@end display
@cindex Gnumeric
cell containing the first datum for the variable.
If this cell is of string (text) format, then the width of the variable is
determined from the length of the string it contains, unless the
-@subcmd{ASSUMEDVARWIDTH} subcommand is given.
+@subcmd{ASSUMEDSTRWIDTH} subcommand is given.
The @subcmd{SHEET} subcommand specifies the sheet within the spreadsheet file to read.
There are two forms of the @subcmd{SHEET} subcommand.
If @subcmd{/READNAMES=OFF} is
used, then the variables receive automatically assigned names.
-The @subcmd{ASSUMEDVARWIDTH} subcommand specifies the maximum width of string
+The @subcmd{ASSUMEDSTRWIDTH} subcommand specifies the maximum width of string
variables read from the file.
If omitted, the default value is determined from the length of the
string in the first spreadsheet cell for each variable.
GET DATA /TYPE=PSQL
/CONNECT=@{@var{connection info}@}
/SQL=@{@var{query}@}
- [/ASSUMEDVARWIDTH=@var{w}]
+ [/ASSUMEDSTRWIDTH=@var{w}]
[/UNENCRYPTED]
[/BSIZE=@var{n}].
@end display
The @subcmd{SQL} subcommand is mandatory.
It must be a valid SQL string to retrieve data from the database.
-The @subcmd{ASSUMEDVARWIDTH} subcommand specifies the maximum width of string
+The @subcmd{ASSUMEDSTRWIDTH} subcommand specifies the maximum width of string
variables read from the database.
If omitted, the default value is determined from the length of the
string in the first value read for each variable.
[ENCODING='@var{encoding}']
[/ARRANGEMENT=@{DELIMITED,FIXED@}]
[/FIRSTCASE=@{@var{first_case}@}]
- [/IMPORTCASE=@{ALL,FIRST @var{max_cases},PERCENT @var{percent}@}]
+ [/IMPORTCASES=...]
@dots{}additional subcommands depending on ARRANGEMENT@dots{}
@end display
to the number of the first line to read: 2 to skip the first line, 3
to skip the first two lines, and so on.
-@subcmd{IMPORTCASE} can be used to limit the number of cases read from the
-input file. With the default setting, ALL, all cases in the file are
-read. Specify FIRST @var{max_cases} to read at most @var{max_cases} cases
-from the file. Use @subcmd{PERCENT @var{percent}} to read only @var{percent}
-percent, approximately, of the cases contained in the file. (The
-percentage is approximate, because there is no way to accurately count
-the number of cases in the file without reading the entire file. The
-number of cases in some kinds of unusual files cannot be estimated;
-@pspp{} will read all cases in such files.)
+@subcmd{IMPORTCASES} is ignored, for compatibility. Use @cmd{N OF
+CASES} to limit the number of cases read from a file (@pxref{N OF
+CASES}), or @cmd{SAMPLE} to obtain a random sample of cases
+(@pxref{SAMPLE}).
-@subcmd{FIRSTCASE} and @subcmd{IMPORTCASE} may be used with delimited and fixed-format
-data. The remaining subcommands, which apply only to one of the two file
-arrangements, are described below.
+The remaining subcommands apply only to one of the two file
+arrangements, described below.
@menu
* GET DATA /TYPE=TXT /ARRANGEMENT=DELIMITED::
[/IMPORTCASE=@{ALL,FIRST @var{max_cases},PERCENT @var{percent}@}]
/DELIMITERS="@var{delimiters}"
- [/QUALIFIER="@var{quotes}" [/ESCAPE]]
+ [/QUALIFIER="@var{quotes}"
[/DELCASE=@{LINE,VARIABLES @var{n_variables}@}]
/VARIABLES=@var{del_var1} [@var{del_var2}]@dots{}
where each @var{del_var} takes the form:
instead of terminating it. The ability to specify more than one quote
character is a @pspp{} extension.
-By default, a character specified on @subcmd{QUALIFIER} cannot itself be
-embedded within a field that it quotes, because the quote character
-always terminates the quoted field. With ESCAPE, however, a doubled
-quote character within a quoted field inserts a single instance of the
-quote into the field. For example, if @samp{'} is specified on
-@subcmd{QUALIFIER}, then without ESCAPE @code{'a''b'} specifies a pair of
-fields that contain @samp{a} and @samp{b}, but with ESCAPE it
-specifies a single field that contains @samp{a'b}. ESCAPE is a @pspp{}
-extension.
+The character specified on @subcmd{QUALIFIER} can be embedded within a
+field that it quotes by doubling the qualifier. For example, if
+@samp{'} is specified on @subcmd{QUALIFIER}, then @code{'a''b'}
+specifies a field that contains @samp{a'b}.
The @subcmd{DELCASE} subcommand controls how data may be broken across lines in
the data file. With LINE, the default setting, each line must contain
SAVE
/OUTFILE=@{'@var{file_name}',@var{file_handle}@}
/UNSELECTED=@{RETAIN,DELETE@}
- /@{COMPRESSED,UNCOMPRESSED@}
+ /@{UNCOMPRESSED,COMPRESSED,ZCOMPRESSED@}
/PERMISSIONS=@{WRITEABLE,READONLY@}
/DROP=@var{var_list}
/KEEP=@var{var_list}
These can be excluded by specifying @subcmd{DELETE} on the @subcmd{UNSELECTED}
subcommand. Specifying @subcmd{RETAIN} makes the default explicit.
-The @subcmd{COMPRESS} and @subcmd{UNCOMPRESS} subcommand determine whether
-the saved system file is compressed. By default, system files are compressed.
-This default can be changed with the SET command (@pxref{SET}).
+The @subcmd{UNCOMPRESSED}, @subcmd{COMPRESSED}, and
+@subcmd{ZCOMPRESSED} subcommand determine the system file's
+compression level:
+
+@table @code
+@item UNCOMPRESSED
+Data is not compressed. Each numeric value uses 8 bytes of disk
+space. Each string value uses one byte per column width, rounded up
+to a multiple of 8 bytes.
+
+@item COMPRESSED
+Data is compressed with a simple algorithm. Each integer numeric
+value between @minus{}99 and 151, inclusive, or system missing value
+uses one byte of disk space. Each 8-byte segment of a string that
+consists only of spaces uses 1 byte. Any other numeric value or
+8-byte string segment uses 9 bytes of disk space.
+
+@item ZCOMPRESSED
+Data is compressed with the ``deflate'' compression algorithm
+specified in RFC@tie{}1951 (the same algorithm used by
+@command{gzip}). Files written with this compression level cannot be
+read by PSPP 0.8.1 or earlier or by SPSS 20 or earlier.
+@end table
+
+@subcmd{COMPRESSED} is the default compression level. The SET command
+(@pxref{SET}) can change this default.
The @subcmd{PERMISSIONS} subcommand specifies permissions for the new system
file. WRITEABLE, the default, creates the file with read and write
@cmd{SAVE} causes the data to be read. It is a procedure.
+@node SAVE DATA COLLECTION
+@section SAVE DATA COLLECTION
+@vindex SAVE DATA COLLECTION
+
+@display
+SAVE DATA COLLECTION
+ /OUTFILE=@{'@var{file_name}',@var{file_handle}@}
+ /METADATA=@{'@var{file_name}',@var{file_handle}@}
+ /@{UNCOMPRESSED,COMPRESSED,ZCOMPRESSED@}
+ /PERMISSIONS=@{WRITEABLE,READONLY@}
+ /DROP=@var{var_list}
+ /KEEP=@var{var_list}
+ /VERSION=@var{version}
+ /RENAME=(@var{src_names}=@var{target_names})@dots{}
+ /NAMES
+ /MAP
+@end display
+
+Like @cmd{SAVE}, @cmd{SAVE DATA COLLECTION} writes the dictionary and
+data in the active dataset to a system file. In addition, it writes
+metadata to an additional XML metadata file.
+
+OUTFILE is required. Specify the system file to be written as a
+string file name or a file handle (@pxref{File Handles}).
+
+METADATA is also required. Specify the metadata file to be written as
+a string file name or a file handle. Metadata files customarily use a
+@file{.mdd} extension.
+
+The current implementation of this command only outputs an
+approximation of the metadata file format. Please report bugs.
+
+Other subcommands are optional. They have the same meanings as in the
+@cmd{SAVE} command.
+
+@cmd{SAVE DATA COLLECTION} causes the data to be read. It is a
+procedure.
+
@node SAVE TRANSLATE
@section SAVE TRANSLATE
@vindex SAVE TRANSLATE
numeric user-missing values like system-missing values and string
user-missing values as all spaces.
-By default, all the variables in the active dataset dictionary are saved
-to the system file, but @subcmd{DROP} or @subcmd{KEEP} can select a subset of variable
-to save. The @subcmd{RENAME} subcommand can also be used to change the names
-under which variables are saved. @subcmd{UNSELECTED} determines whether cases
-filtered out by the @cmd{FILTER} command are written to the output file.
-These subcommands have the same syntax and meaning as on the
-@cmd{SAVE} command (@pxref{SAVE}).
+By default, all the variables in the active dataset dictionary are
+saved to the system file, but @subcmd{DROP} or @subcmd{KEEP} can
+select a subset of variable to save. The @subcmd{RENAME} subcommand
+can also be used to change the names under which variables are saved;
+because they are used only in the output, these names do not have to
+conform to the usual PSPP variable naming rules. @subcmd{UNSELECTED}
+determines whether cases filtered out by the @cmd{FILTER} command are
+written to the output file. These subcommands have the same syntax
+and meaning as on the @cmd{SAVE} command (@pxref{SAVE}).
Each supported file type has additional subcommands, explained in
separate sections below.
@vindex SYSFILE INFO
@display
-SYSFILE INFO FILE='@var{file_name}'.
+SYSFILE INFO FILE='@var{file_name}' [ENCODING='@var{encoding}'].
@end display
-@cmd{SYSFILE INFO} reads the dictionary in a system file and
-displays the information in its dictionary.
+@cmd{SYSFILE INFO} reads the dictionary in an SPSS system file,
+SPSS/PC+ system file, or SPSS portable file, and displays the
+information in its dictionary.
+
+Specify a file name or file handle. @cmd{SYSFILE INFO} reads that
+file and displays information on its dictionary.
-Specify a file name or file handle. @cmd{SYSFILE INFO} reads that file as
-a system file and displays information on its dictionary.
+@pspp{} automatically detects the encoding of string data in the file,
+when possible. The character encoding of old SPSS system files cannot
+always be guessed correctly, and SPSS/PC+ system files do not include
+any indication of their encoding. Specify the @subcmd{ENCODING}
+subcommand with an @acronym{IANA} character set name as its string
+argument to override the default, or specify @code{ENCODING='DETECT'}
+to analyze and report possibly valid encodings for the system file.
+The @subcmd{ENCODING} subcommand is a @pspp{} extension.
@cmd{SYSFILE INFO} does not affect the current active dataset.
/MAP
@end display
-The @cmd{EXPORT} transformation writes the active dataset dictionary and
+The @cmd{XEXPORT} transformation writes the active dataset dictionary and
data to a specified portable file.
This transformation is a @pspp{} extension.
@display
XSAVE
/OUTFILE='@var{file_name}'
- /@{COMPRESSED,UNCOMPRESSED@}
+ /@{UNCOMPRESSED,COMPRESSED,ZCOMPRESSED@}
/PERMISSIONS=@{WRITEABLE,READONLY@}
/DROP=@var{var_list}
/KEEP=@var{var_list}
projects / pspp / blobdiff