-@node Data Input and Output, System and Portable Files, Expressions, Top
+@node Data Input and Output
@chapter Data Input and Output
@cindex input
@cindex output
Data are the focus of the PSPP language.
Each datum belongs to a @dfn{case} (also called an @dfn{observation}).
-Each case represents an individual or `experimental unit'.
+Each case represents an individual or ``experimental unit''.
For example, in the results of a survey, the names of the respondents,
-their sex, age @i{etc}. and their responses are all data and the data
+their sex, age, etc.@: and their responses are all data and the data
pertaining to single respondent is a case.
This chapter examines
the PSPP commands for defining variables and reading and writing data.
+There are alternative commands to read data from predefined sources
+such as system files or databases (@xref{GET, GET DATA}.)
-@quotation
-@strong{Please note:} Data is not actually read until a procedure is
-executed. These commands tell PSPP how to read data, but they
-do not @emph{cause} PSPP to read data.
+@quotation Note
+These commands tell PSPP how to read data, but the data will not
+actually be read until a procedure is executed.
@end quotation
@menu
* BEGIN DATA:: Embed data within a syntax file.
-* CLEAR TRANSFORMATIONS:: Clear pending transformations.
+* CLOSE FILE HANDLE:: Close a file handle.
+* DATAFILE ATTRIBUTE:: Set custom attributes on data files.
* DATA LIST:: Fundamental data reading command.
* END CASE:: Output the current case.
* END FILE:: Terminate the current input program.
-* FILE HANDLE:: Support for fixed-length records.
+* FILE HANDLE:: Support for special file formats.
* INPUT PROGRAM:: Support for complex input programs.
* LIST:: List cases in the active file.
-* MATRIX DATA:: Read matrices in text format.
* NEW FILE:: Clear the active file and dictionary.
* PRINT:: Display values in print formats.
* PRINT EJECT:: Eject the current page then print.
* WRITE:: Display values in write formats.
@end menu
-@node BEGIN DATA, CLEAR TRANSFORMATIONS, Data Input and Output, Data Input and Output
+@node BEGIN DATA
@section BEGIN DATA
@vindex BEGIN DATA
@vindex END DATA
procedure must be used before @cmd{BEGIN DATA} (@pxref{DATA LIST}).
@cmd{BEGIN DATA} and @cmd{END DATA} must be used together. @cmd{END
DATA} must appear by itself on a single line, with no leading
-whitespace and exactly one space between the words @code{END} and
-@code{DATA}, followed immediately by the terminal dot, like this:
+white space and exactly one space between the words @code{END} and
+@code{DATA}, like this:
@example
END DATA.
@end example
-@node CLEAR TRANSFORMATIONS, DATA LIST, BEGIN DATA, Data Input and Output
-@section CLEAR TRANSFORMATIONS
-@vindex CLEAR TRANSFORMATIONS
+@node CLOSE FILE HANDLE
+@section CLOSE FILE HANDLE
@display
-CLEAR TRANSFORMATIONS.
+CLOSE FILE HANDLE handle_name.
@end display
-@cmd{CLEAR TRANSFORMATIONS} clears out all pending
-transformations. It does not cancel the current input program. It is
-valid only when PSPP is interactive, not in syntax files.
+@cmd{CLOSE FILE HANDLE} disassociates the name of a file handle with a
+given file. The only specification is the name of the handle to close.
+Afterward
+@cmd{FILE HANDLE}.
-@node DATA LIST, END CASE, CLEAR TRANSFORMATIONS, Data Input and Output
+If the file handle name refers to a scratch file, then the storage
+associated with the scratch file in memory or on disk will be freed.
+If the scratch file is in use, e.g.@: it has been specified on a
+@cmd{GET} command whose execution has not completed, then freeing is
+delayed until it is no longer in use.
+
+The file named INLINE, which represents data entered between @cmd{BEGIN
+DATA} and @cmd{END DATA}, cannot be closed. Attempts to close it with
+@cmd{CLOSE FILE HANDLE} have no effect.
+
+@cmd{CLOSE FILE HANDLE} is a PSPP extension.
+
+@node DATAFILE ATTRIBUTE
+@section DATAFILE ATTRIBUTE
+@vindex DATAFILE ATTRIBUTE
+
+@display
+DATAFILE ATTRIBUTE
+ ATTRIBUTE=name('value') [name('value')]@dots{}
+ ATTRIBUTE=name@b{[}index@b{]}('value') [name@b{[}index@b{]}('value')]@dots{}
+ DELETE=name [name]@dots{}
+ DELETE=name@b{[}index@b{]} [name@b{[}index@b{]}]@dots{}
+@end display
+
+@cmd{DATAFILE ATTRIBUTE} adds, modifies, or removes user-defined
+attributes associated with the active file. Custom data file
+attributes are not interpreted by PSPP, but they are saved as part of
+system files and may be used by other software that reads them.
+
+Use the ATTRIBUTE subcommand to add or modify a custom data file
+attribute. Specify the name of the attribute as an identifier
+(@pxref{Tokens}), followed by the desired value, in parentheses, as a
+quoted string. Attribute names that begin with @code{$} are reserved
+for PSPP's internal use, and attribute names that begin with @code{@@}
+or @code{$@@} are not displayed by most PSPP commands that display
+other attributes. Other attribute names are not treated specially.
+
+Attributes may also be organized into arrays. To assign to an array
+element, add an integer array index enclosed in square brackets
+(@code{[} and @code{]}) between the attribute name and value. Array
+indexes start at 1, not 0. An attribute array that has a single
+element (number 1) is not distinguished from a non-array attribute.
+
+Use the DELETE subcommand to delete an attribute. Specify an
+attribute name by itself to delete an entire attribute, including all
+array elements for attribute arrays. Specify an attribute name
+followed by an array index in square brackets to delete a single
+element of an attribute array. In the latter case, all the array
+elements numbered higher than the deleted element are shifted down,
+filling the vacated position.
+
+To associate custom attributes with particular variables, instead of
+with the entire active file, use @cmd{VARIABLE ATTRIBUTE} (@pxref{VARIABLE ATTRIBUTE}) instead.
+
+@cmd{DATAFILE ATTRIBUTE} takes effect immediately. It is not affected
+by conditional and looping structures such as @cmd{DO IF} or
+@cmd{LOOP}.
+
+@node DATA LIST
@section DATA LIST
@vindex DATA LIST
@cindex reading data from a file
Each form of @cmd{DATA LIST} is described in detail below.
+@xref{GET DATA}, for a command that offers a few enhancements over
+DATA LIST and that may be substituted for DATA LIST in many
+situations.
+
@menu
* DATA LIST FIXED:: Fixed columnar locations for data.
* DATA LIST FREE:: Any spacing you like.
* DATA LIST LIST:: Each case must be on a single line.
@end menu
-@node DATA LIST FIXED, DATA LIST FREE, DATA LIST, DATA LIST
+@node DATA LIST FIXED
@subsection DATA LIST FIXED
@vindex DATA LIST FIXED
@cindex reading fixed-format data
@display
DATA LIST [FIXED]
@{TABLE,NOTABLE@}
- FILE='filename'
- RECORDS=record_count
- END=end_var
+ [FILE='file-name' [ENCODING='encoding']]
+ [RECORDS=record_count]
+ [END=end_var]
+ [SKIP=record_count]
/[line_no] var_spec@dots{}
where each var_spec takes one of the forms
keyword FIXED is optional.
The FILE subcommand must be used if input is to be taken from an
-external file. It may be used to specify a filename as a string or a
-file handle (@pxref{FILE HANDLE}). If the FILE subcommand is not used,
+external file. It may be used to specify a file name as a string or a
+file handle (@pxref{File Handles}). If the FILE subcommand is not used,
then input is assumed to be specified within the command file using
@cmd{BEGIN DATA}@dots{}@cmd{END DATA} (@pxref{BEGIN DATA}).
+The ENCODING subcommand may only be used if the FILE subcommand is also used.
+It specifies the character encoding of the file.
The optional RECORDS subcommand, which takes a single integer as an
argument, is used to specify the number of lines per record. If RECORDS
The END subcommand is only useful in conjunction with @cmd{INPUT
PROGRAM}. @xref{INPUT PROGRAM}, for details.
+The optional SKIP subcommand specifies a number of records to skip at
+the beginning of an input file. It can be used to skip over a row
+that contains variable names, for example.
+
@cmd{DATA LIST} can optionally output a table describing how the data file
will be read. The TABLE subcommand enables this output, and NOTABLE
disables it. The default is to output the table.
Each variable specification consists of a list of variable names
followed by a description of their location on the input line. Sets of
-variables may specified using the @code{DATA LIST} TO convention
+variables may be specified using the @code{DATA LIST} TO convention
(@pxref{Sets of
Variables}). There are two ways to specify the location of the variable
on the line: columnar style and FORTRAN style.
are specified after the variable name, separated by a dash (@samp{-}).
For instance, the third through fifth columns on a line would be
specified @samp{3-5}. By default, variables are considered to be in
-@samp{F} format (@pxref{Input/Output Formats}). (This default can be
+@samp{F} format (@pxref{Input and Output Formats}). (This default can be
changed; see @ref{SET} for more information.)
In columnar style, to use a variable format other than the default,
specification with @var{d} decimal places also has @var{d} implied
decimal places.
-In addition to the standard format specifiers (@pxref{Input/Output
+In addition to the standard format specifiers (@pxref{Input and Output
Formats}), FORTRAN style defines some extensions:
@table @asis
* DATA LIST FIXED Examples:: Examples of DATA LIST FIXED.
@end menu
-@node DATA LIST FIXED Examples, , DATA LIST FIXED, DATA LIST FIXED
+@node DATA LIST FIXED Examples
@unnumberedsubsubsec Examples
@enumerate
@itemize @bullet
@item
-@code{NAME}, a 10-character-wide long string variable, in columns 1
+@code{NAME}, a 10-character-wide string variable, in columns 1
through 10.
@item
@code{ID}, a numeric variable, in columns 1-5 of the first record.
@item
-@code{NAME}, a 30-character long string variable, in columns 7-36 of the
+@code{NAME}, a 30-character string variable, in columns 7-36 of the
first record.
@item
-@code{SURNAME}, a 30-character long string variable, in columns 38-67 of
+@code{SURNAME}, a 30-character string variable, in columns 38-67 of
the first record.
@item
-@code{MINITIAL}, a 1-character short string variable, in column 69 of
+@code{MINITIAL}, a 1-character string variable, in column 69 of
the first record.
@item
@end enumerate
-@node DATA LIST FREE, DATA LIST LIST, DATA LIST FIXED, DATA LIST
+@node DATA LIST FREE
@subsection DATA LIST FREE
@vindex DATA LIST FREE
DATA LIST FREE
[(@{TAB,'c'@}, @dots{})]
[@{NOTABLE,TABLE@}]
- FILE='filename'
- END=end_var
+ [FILE='file-name' [ENCODING='encoding']]
+ [SKIP=record_cnt]
/var_spec@dots{}
where each var_spec takes one of the forms
The NOTABLE and TABLE subcommands are as in @cmd{DATA LIST FIXED} above.
NOTABLE is the default.
-The FILE and END subcommands are as in @cmd{DATA LIST FIXED} above.
+The FILE and SKIP subcommands are as in @cmd{DATA LIST FIXED} above.
The variables to be parsed are given as a single list of variable names.
This list must be introduced by a single slash (@samp{/}). The set of
variable names may contain format specifications in parentheses
-(@pxref{Input/Output Formats}). Format specifications apply to all
+(@pxref{Input and Output Formats}). Format specifications apply to all
variables back to the previous parenthesized format specification.
In addition, an asterisk may be used to indicate that all variables
Specified field widths are ignored on input, although all normal limits
on field width apply, but they are honored on output.
-@node DATA LIST LIST, , DATA LIST FREE, DATA LIST
+@node DATA LIST LIST
@subsection DATA LIST LIST
@vindex DATA LIST LIST
DATA LIST LIST
[(@{TAB,'c'@}, @dots{})]
[@{NOTABLE,TABLE@}]
- FILE='filename'
- END=end_var
+ [FILE='file-name' [ENCODING='encoding']]
+ [SKIP=record_count]
/var_spec@dots{}
where each var_spec takes one of the forms
record. If more or fewer fields are found on an input line than
expected, an appropriate diagnostic is issued.
-@node END CASE, END FILE, DATA LIST, Data Input and Output
+@node END CASE
@section END CASE
@vindex END CASE
@cmd{END CASE} is used only within @cmd{INPUT PROGRAM} to output the
current case. @xref{INPUT PROGRAM}, for details.
-@node END FILE, FILE HANDLE, END CASE, Data Input and Output
+@node END FILE
@section END FILE
@vindex END FILE
@cmd{END FILE} is used only within @cmd{INPUT PROGRAM} to terminate
the current input program. @xref{INPUT PROGRAM}.
-@node FILE HANDLE, INPUT PROGRAM, END FILE, Data Input and Output
+@node FILE HANDLE
@section FILE HANDLE
@vindex FILE HANDLE
@display
-FILE HANDLE handle_name
- /NAME='filename'
- /MODE=@{CHARACTER,IMAGE@}
- /LRECL=rec_len
- /TABWIDTH=tab_width
+For text files:
+ FILE HANDLE handle_name
+ /NAME='file-name'
+ [/MODE=CHARACTER]
+ /TABWIDTH=tab_width
+
+For binary files in native encoding with fixed-length records:
+ FILE HANDLE handle_name
+ /NAME='file-name'
+ /MODE=IMAGE
+ [/LRECL=rec_len]
+
+For binary files in native encoding with variable-length records:
+ FILE HANDLE handle_name
+ /NAME='file-name'
+ /MODE=BINARY
+ [/LRECL=rec_len]
+
+For binary files encoded in EBCDIC:
+ FILE HANDLE handle_name
+ /NAME='file-name'
+ /MODE=360
+ /RECFORM=@{FIXED,VARIABLE,SPANNED@}
+ [/LRECL=rec_len]
+
+To explicitly declare a scratch handle:
+ FILE HANDLE handle_name
+ /MODE=SCRATCH
@end display
Use @cmd{FILE HANDLE} to associate a file handle name with a file and
its attributes, so that later commands can refer to the file by its
-handle name. Because names of text files can be specified directly on
-commands that access files, @cmd{FILE HANDLE} is only needed when a
+handle name. Names of text files can be specified directly on
+commands that access files, so that @cmd{FILE HANDLE} is only needed when a
file is not an ordinary file containing lines of text. However,
@cmd{FILE HANDLE} may be used even for text files, and it may be
easier to specify a file's name once and later refer to it by an
abstract handle.
-Specify the file handle name as an identifier. Any given identifier may
-only appear once in a PSPP run. File handles may not be reassigned to a
-different file. The file handle name must immediately follow the @cmd{FILE
-HANDLE} command name.
+Specify the file handle name as the identifier immediately following the
+@cmd{FILE HANDLE} command name. The identifier INLINE is reserved for
+representing data embedded in the syntax file (@pxref{BEGIN DATA}) The
+file handle name must not already have been used in a previous
+invocation of @cmd{FILE HANDLE}, unless it has been closed by an
+intervening command (@pxref{CLOSE FILE HANDLE}).
+
+The effect and syntax of FILE HANDLE depends on the selected MODE:
+
+@itemize
+@item
+In CHARACTER mode, the default, the data file is read as a text file,
+according to the local system's conventions, and each text line is
+read as one record.
+
+In CHARACTER mode only, tabs are expanded to spaces by input programs,
+except by @cmd{DATA LIST FREE} with explicitly specified delimiters.
+Each tab is 4 characters wide by default, but TABWIDTH (a PSPP
+extension) may be used to specify an alternate width. Use a TABWIDTH
+of 0 to suppress tab expansion.
+
+@item
+In IMAGE mode, the data file is treated as a series of fixed-length
+binary records. LRECL should be used to specify the record length in
+bytes, with a default of 1024. On input, it is an error if an IMAGE
+file's length is not a integer multiple of the record length. On
+output, each record is padded with spaces or truncated, if necessary,
+to make it exactly the correct length.
+
+@item
+In BINARY mode, the data file is treated as a series of
+variable-length binary records. LRECL may be specified, but its value
+is ignored. The data for each record is both preceded and followed by
+a 32-bit signed integer in little-endian byte order that specifies the
+length of the record. (This redundancy permits records in these
+files to be efficiently read in reverse order, although PSPP always
+reads them in forward order.) The length does not include either
+integer.
+
+@item
+Mode 360 reads and writes files in formats first used for tapes in the
+1960s on IBM mainframe operating systems and still supported today by
+the modern successors of those operating systems. For more
+information, see @cite{OS/400 Tape and Diskette Device Programming},
+available on IBM's website.
+
+Alphanumeric data in mode 360 files are encoded in EBCDIC. PSPP
+translates EBCDIC to or from the host's native format as necessary on
+input or output, using an ASCII/EBCDIC translation that is one-to-one,
+so that a ``round trip'' from ASCII to EBCDIC back to ASCII, or vice
+versa, always yields exactly the original data.
+
+The RECFORM subcommand is required in mode 360. The precise file
+format depends on its setting:
+
+@table @asis
+@item F
+@itemx FIXED
+This record format is equivalent to IMAGE mode, except for EBCDIC
+translation.
+
+IBM documentation calls this @code{*F} (fixed-length, deblocked)
+format.
+
+@item V
+@itemx VARIABLE
+The file comprises a sequence of zero or more variable-length blocks.
+Each block begins with a 4-byte @dfn{block descriptor word} (BDW).
+The first two bytes of the BDW are an unsigned integer in big-endian
+byte order that specifies the length of the block, including the BDW
+itself. The other two bytes of the BDW are ignored on input and
+written as zeros on output.
+
+Following the BDW, the remainder of each block is a sequence of one or
+more variable-length records, each of which in turn begins with a
+4-byte @dfn{record descriptor word} (RDW) that has the same format as
+the BDW. Following the RDW, the remainder of each record is the
+record data.
+
+The maximum length of a record in VARIABLE mode is 65,527 bytes:
+65,535 bytes (the maximum value of a 16-bit unsigned integer), minus 4
+bytes for the BDW, minus 4 bytes for the RDW.
+
+In mode VARIABLE, LRECL specifies a maximum, not a fixed, record
+length, in bytes. The default is 8,192.
+
+IBM documentation calls this @code{*VB} (variable-length, blocked,
+unspanned) format.
+
+@item VS
+@itemx SPANNED
+The file format is like that of VARIABLE mode, except that logical
+records may be split among multiple physical records (called
+@dfn{segments}) or blocks. In SPANNED mode, the third byte of each
+RDW is called the segment control character (SCC). Odd SCC values
+cause the segment to be appended to a record buffer maintained in
+memory; even values also append the segment and then flush its
+contents to the input procedure. Canonically, SCC value 0 designates
+a record not spanned among multiple segments, and values 1 through 3
+designate the first segment, the last segment, or an intermediate
+segment, respectively, within a multi-segment record. The record
+buffer is also flushed at end of file regardless of the final record's
+SCC.
+
+The maximum length of a logical record in VARIABLE mode is limited
+only by memory available to PSPP. Segments are limited to 65,527
+bytes, as in VARIABLE mode.
+
+This format is similar to what IBM documentation call @code{*VS}
+(variable-length, deblocked, spanned) format.
+@end table
+
+In mode 360, fields of type A that extend beyond the end of a record
+read from disk are padded with spaces in the host's native character
+set, which are then translated from EBCDIC to the native character
+set. Thus, when the host's native character set is based on ASCII,
+these fields are effectively padded with character @code{X'80'}. This
+wart is implemented for compatibility.
+
+@item
+SCRATCH mode is a PSPP extension that designates the file handle as a
+scratch file handle.
+Its use is usually unnecessary because file handle names that begin with
+@samp{#} are assumed to refer to scratch files. @pxref{File Handles},
+for more information.
+@end itemize
The NAME subcommand specifies the name of the file associated with the
-handle. It is the only required subcommand.
-
-MODE specifies a file mode. In CHARACTER mode, the default, the data
-file is opened in ANSI C text mode, so that local end of line
-conventions are followed, and each text line is read as one record.
-In CHARACTER mode, most input programs will expand tabs to spaces
-(@cmd{DATA LIST FREE} with explicitly specified delimiters is an
-exception). By default, each tab is 4 characters wide, but an
-alternate width may be specified on TABWIDTH. A tab width of 0
-suppresses tab expansion entirely.
-
-By contrast, in BINARY mode, the data file is opened in ANSI C binary
-mode and records are a fixed length. In BINARY mode, LRECL specifies
-the record length in bytes, with a default of 1024. Tab characters
-are never expanded to spaces in binary mode.
-
-@node INPUT PROGRAM, LIST, FILE HANDLE, Data Input and Output
+handle. It is required in all modes but SCRATCH mode, in which its
+use is forbidden.
+
+@node INPUT PROGRAM
@section INPUT PROGRAM
@vindex INPUT PROGRAM
All this is very confusing. A few examples should help to clarify.
+@c If you change this example, change the regression test1 in
+@c tests/command/input-program.sh to match.
@example
INPUT PROGRAM.
DATA LIST NOTABLE FILE='a.data'/X 1-10.
Y from file @file{b.data}. If one file is shorter than the other then
the extra data in the longer file is ignored.
+@c If you change this example, change the regression test2 in
+@c tests/command/input-program.sh to match.
@example
INPUT PROGRAM.
NUMERIC #A #B.
field is set to the system-missing value alongside the present value for
the remaining length of the longer file.
+@c If you change this example, change the regression test3 in
+@c tests/command/input-program.sh to match.
@example
INPUT PROGRAM.
NUMERIC #A #B.
The above example reads data from file @file{a.data}, then from
@file{b.data}, and concatenates them into a single active file.
+@c If you change this example, change the regression test4 in
+@c tests/command/input-program.sh to match.
@example
INPUT PROGRAM.
NUMERIC #EOF.
The above example does the same thing as the previous example, in a
different way.
+@c If you change this example, make similar changes to the regression
+@c test5 in tests/command/input-program.sh.
@example
INPUT PROGRAM.
LOOP #I=1 TO 50.
The above example causes an active file to be created consisting of 50
random variates between 0 and 10.
-@node LIST, MATRIX DATA, INPUT PROGRAM, Data Input and Output
+@node LIST
@section LIST
@vindex LIST
@cmd{LIST} is a procedure. It causes the data to be read.
-@node MATRIX DATA, NEW FILE, LIST, Data Input and Output
-@section MATRIX DATA
-@vindex MATRIX DATA
-
-@display
-MATRIX DATA
- /VARIABLES=var_list
- /FILE='filename'
- /FORMAT=@{LIST,FREE@} @{LOWER,UPPER,FULL@} @{DIAGONAL,NODIAGONAL@}
- /SPLIT=@{new_var,var_list@}
- /FACTORS=var_list
- /CELLS=n_cells
- /N=n
- /CONTENTS=@{N_VECTOR,N_SCALAR,N_MATRIX,MEAN,STDDEV,COUNT,MSE,
- DFE,MAT,COV,CORR,PROX@}
-@end display
-
-@cmd{MATRIX DATA} command reads square matrices in one of several textual
-formats. @cmd{MATRIX DATA} clears the dictionary and replaces it and
-reads a
-data file.
-
-Use VARIABLES to specify the variables that form the rows and columns of
-the matrices. You may not specify a variable named @code{VARNAME_}. You
-should specify VARIABLES first.
-
-Specify the file to read on FILE, either as a file name string or a file
-handle (@pxref{FILE HANDLE}). If FILE is not specified then matrix data
-must immediately follow @cmd{MATRIX DATA} with a @cmd{BEGIN
-DATA}@dots{}@cmd{END DATA}
-construct (@pxref{BEGIN DATA}).
-
-The FORMAT subcommand specifies how the matrices are formatted. LIST,
-the default, indicates that there is one line per row of matrix data;
-FREE allows single matrix rows to be broken across multiple lines. This
-is analogous to the difference between @cmd{DATA LIST FREE} and
-@cmd{DATA LIST LIST}
-(@pxref{DATA LIST}). LOWER, the default, indicates that the lower
-triangle of the matrix is given; UPPER indicates the upper triangle; and
-FULL indicates that the entire matrix is given. DIAGONAL, the default,
-indicates that the diagonal is part of the data; NODIAGONAL indicates
-that it is omitted. DIAGONAL/NODIAGONAL have no effect when FULL is
-specified.
-
-The SPLIT subcommand is used to specify @cmd{SPLIT FILE} variables for the
-input matrices (@pxref{SPLIT FILE}). Specify either a single variable
-not specified on VARIABLES, or one or more variables that are specified
-on VARIABLES. In the former case, the SPLIT values are not present in
-the data and ROWTYPE_ may not be specified on VARIABLES. In the latter
-case, the SPLIT values are present in the data.
-
-Specify a list of factor variables on FACTORS. Factor variables must
-also be listed on VARIABLES. Factor variables are used when there are
-some variables where, for each possible combination of their values,
-statistics on the matrix variables are included in the data.
-
-If FACTORS is specified and ROWTYPE_ is not specified on VARIABLES, the
-CELLS subcommand is required. Specify the number of factor variable
-combinations that are given. For instance, if factor variable A has 2
-values and factor variable B has 3 values, specify 6.
-
-The N subcommand specifies a population number of observations. When N
-is specified, one N record is output for each @cmd{SPLIT FILE}.
-
-Use CONTENTS to specify what sort of information the matrices include.
-Each possible option is described in more detail below. When ROWTYPE_
-is specified on VARIABLES, CONTENTS is optional; otherwise, if CONTENTS
-is not specified then /CONTENTS=CORR is assumed.
-
-@table @asis
-@item N
-@item N_VECTOR
-Number of observations as a vector, one value for each variable.
-@item N_SCALAR
-Number of observations as a single value.
-@item N_MATRIX
-Matrix of counts.
-@item MEAN
-Vector of means.
-@item STDDEV
-Vector of standard deviations.
-@item COUNT
-Vector of counts.
-@item MSE
-Vector of mean squared errors.
-@item DFE
-Vector of degrees of freedom.
-@item MAT
-Generic matrix.
-@item COV
-Covariance matrix.
-@item CORR
-Correlation matrix.
-@item PROX
-Proximities matrix.
-@end table
-
-The exact semantics of the matrices read by @cmd{MATRIX DATA} are complex.
-Right now @cmd{MATRIX DATA} isn't too useful due to a lack of procedures
-accepting or producing related data, so these semantics aren't
-documented. Later, they'll be described here in detail.
-
-@node NEW FILE, PRINT, MATRIX DATA, Data Input and Output
+@node NEW FILE
@section NEW FILE
@vindex NEW FILE
@cmd{NEW FILE} command clears the current active file.
-@node PRINT, PRINT EJECT, NEW FILE, Data Input and Output
+@node PRINT
@section PRINT
@vindex PRINT
@display
PRINT
- OUTFILE='filename'
+ OUTFILE='file-name'
RECORDS=n_lines
@{NOTABLE,TABLE@}
- /[line_no] arg@dots{}
+ [/[line_no] arg@dots{}]
arg takes one of the following forms:
'string' [start-end]
var_list *
@end display
-The @cmd{PRINT} transformation writes variable data to an output file.
-@cmd{PRINT} is executed when a procedure causes the data to be read.
-Follow @cmd{PRINT} by @cmd{EXECUTE} to print variable data without
-invoking a procedure (@pxref{EXECUTE}).
+The @cmd{PRINT} transformation writes variable data to the listing
+file or an output file. @cmd{PRINT} is executed when a procedure
+causes the data to be read. Follow @cmd{PRINT} by @cmd{EXECUTE} to
+print variable data without invoking a procedure (@pxref{EXECUTE}).
-All @cmd{PRINT} subcommands are optional.
+All @cmd{PRINT} subcommands are optional. If no strings or variables
+are specified, PRINT outputs a single blank line.
The OUTFILE subcommand specifies the file to receive the output. The
-file may be a file name as a string or a file handle (@pxref{FILE
-HANDLE}). If OUTFILE is not present then output will be sent to PSPP's
-output listing file.
+file may be a file name as a string or a file handle (@pxref{File
+Handles}). If OUTFILE is not present then output will be sent to
+PSPP's output listing file. When OUTFILE is present, a space is
+inserted at beginning of each output line, even lines that otherwise
+would be blank.
The RECORDS subcommand specifies the number of lines to be output. The
number of lines may optionally be surrounded by parentheses.
truncated to that length, although additional text being added will
again extend the line to that length.
-@node PRINT EJECT, PRINT SPACE, PRINT, Data Input and Output
+@node PRINT EJECT
@section PRINT EJECT
@vindex PRINT EJECT
@display
PRINT EJECT
- OUTFILE='filename'
+ OUTFILE='file-name'
RECORDS=n_lines
@{NOTABLE,TABLE@}
/[line_no] arg@dots{}
var_list *
@end display
-@cmd{PRINT EJECT} writes data to an output file. Before the data is
-written, the current page in the listing file is ejected.
+@cmd{PRINT EJECT} advances to the beginning of a new output page in
+the listing file or output file. It can also output data in the same
+way as @cmd{PRINT}.
+
+All @cmd{PRINT EJECT} subcommands are optional.
+
+Without OUTFILE, PRINT EJECT ejects the current page in
+the listing file, then it produces other output, if any is specified.
+
+With OUTFILE, PRINT EJECT writes its output to the specified file.
+The first line of output is written with @samp{1} inserted in the
+first column. Commonly, this is the only line of output. If
+additional lines of output are specified, these additional lines are
+written with a space inserted in the first column, as with PRINT.
@xref{PRINT}, for more information on syntax and usage.
-@node PRINT SPACE, REREAD, PRINT EJECT, Data Input and Output
+@node PRINT SPACE
@section PRINT SPACE
@vindex PRINT SPACE
@display
-PRINT SPACE OUTFILE='filename' n_lines.
+PRINT SPACE OUTFILE='file-name' n_lines.
@end display
@cmd{PRINT SPACE} prints one or more blank lines to an output file.
The OUTFILE subcommand is optional. It may be used to direct output to
-a file specified by file name as a string or file handle (@pxref{FILE
-HANDLE}). If OUTFILE is not specified then output will be directed to
+a file specified by file name as a string or file handle (@pxref{File
+Handles}). If OUTFILE is not specified then output will be directed to
the listing file.
n_lines is also optional. If present, it is an expression
(@pxref{Expressions}) specifying the number of blank lines to be
printed. The expression must evaluate to a nonnegative value.
-@node REREAD, REPEATING DATA, PRINT SPACE, Data Input and Output
+@node REREAD
@section REREAD
@vindex REREAD
for further processing.
The FILE subcommand, which is optional, is used to specify the file to
-have its line re-read. The file must be specified in the form of a file
-handle (@pxref{FILE HANDLE}). If FILE is not specified then the last
+have its line re-read. The file must be specified as the name of a file
+handle (@pxref{File Handles}). If FILE is not specified then the last
file specified on @cmd{DATA LIST} will be assumed (last file specified
lexically, not in terms of flow-of-control).
Issuing @code{REREAD} multiple times will not back up in the data
file. Instead, it will re-read the same line multiple times.
-@node REPEATING DATA, WRITE, REREAD, Data Input and Output
+@node REPEATING DATA
@section REPEATING DATA
@vindex REPEATING DATA
REPEATING DATA
/STARTS=start-end
/OCCURS=n_occurs
- /FILE='filename'
+ /FILE='file-name'
/LENGTH=length
/CONTINUED[=cont_start-cont_end]
/ID=id_start-id_end=id_var
All other subcommands are optional.
FILE specifies the file to read, either a file name as a string or a
-file handle (@pxref{FILE HANDLE}). If FILE is not present then the
+file handle (@pxref{File Handles}). If FILE is not present then the
default is the last file handle used on @cmd{DATA LIST} (lexically, not in
terms of flow of control).
structure (@pxref{LOOP}). Use @cmd{DATA LIST} before, not after,
@cmd{REPEATING DATA}.
-@node WRITE, , REPEATING DATA, Data Input and Output
+@node WRITE
@section WRITE
@vindex WRITE
@display
WRITE
- OUTFILE='filename'
+ OUTFILE='file-name'
RECORDS=n_lines
@{NOTABLE,TABLE@}
/[line_no] arg@dots{}
@code{WRITE} writes text or binary data to an output file.
-@xref{PRINT}, for more information on syntax and usage. The main
-difference between @code{PRINT} and @code{WRITE} is that @cmd{WRITE}
-uses write formats by default, where PRINT uses print formats.
+@xref{PRINT}, for more information on syntax and usage. @cmd{PRINT}
+and @cmd{WRITE} differ in only a few ways:
+
+@itemize @bullet
+@item
+@cmd{WRITE} uses write formats by default, whereas @cmd{PRINT} uses
+print formats.
-The sole additional difference is that if @cmd{WRITE} is used to send output
-to a binary file, carriage control characters will not be output.
-@xref{FILE HANDLE}, for information on how to declare a file as binary.
-@setfilename ignored
+@item
+@cmd{PRINT} inserts a space between variables unless a format is
+explicitly specified, but @cmd{WRITE} never inserts space between
+variables in output.
+
+@item
+@cmd{PRINT} inserts a space at the beginning of each line that it
+writes to an output file (and @cmd{PRINT EJECT} inserts @samp{1} at
+the beginning of each line that should begin a new page), but
+@cmd{WRITE} does not.
+
+@item
+@cmd{PRINT} outputs the system-missing value according to its
+specified output format, whereas @cmd{WRITE} outputs the
+system-missing value as a field filled with spaces. Binary formats
+are an exception.
+@end itemize
projects / pspp-builds.git / blobdiff