


csv(n)                    CSV processing                   csv(n)


______________________________________________________________________________

NAME
       csv - Procedures to handle CSV data.

SYNOPSIS
       package require Tcl  8.3

       package require csv  ?0.7.1?

       ::csv::iscomplete data

       ::csv::join values {sepChar ,} {delChar "}

       ::csv::joinlist values {sepChar ,} {delChar "}

       ::csv::joinmatrix matrix {sepChar ,} {delChar "}

       ::csv::read2matrix ?-alternate? chan m {sepChar ,} {expand none}

       ::csv::read2queue ?-alternate? chan q {sepChar ,}

       ::csv::report cmd matrix ?chan?

       ::csv::split ?-alternate? line {sepChar ,} {delChar "}

       ::csv::split2matrix ?-alternate? m line {sepChar ,} {expand none}

       ::csv::split2queue ?-alternate? q line {sepChar ,}

       ::csv::writematrix m chan {sepChar ,} {delChar "}

       ::csv::writequeue q chan {sepChar ,} {delChar "}

_________________________________________________________________

DESCRIPTION
       The csv package provides commands to manipulate information in CSV FOR-
       MAT (CSV = Comma Separated Values).

COMMANDS
       The following commands are available:

       ::csv::iscomplete data
              A predicate checking if the argument  data  is  a  complete  csv
              record. The result is a boolean flag indicating the completeness
              of the data. The result is true if the data is complete.

       ::csv::join values {sepChar ,} {delChar "}
              Takes a list of values and returns a string in CSV  format  con-
              taining  these values. The separator character can be defined by
              the caller, but this is optional. The default is ",". The  quot-
              ing  character  can  be  defined  by  the  caller,  but  this is
              optional. The default is '"'.



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csv(n)                    CSV processing                   csv(n)


       ::csv::joinlist values {sepChar ,} {delChar "}
              Takes a list of lists of values and returns a string in CSV for-
              mat  containing  these  values.  The  separator character can be
              defined by the caller, but this is optional. The default is ",".
              The  quoting character can be defined by the caller, but this is
              optional. The default is '"'.  Each element of the outer list is
              considered  a  record,  these  are  separated by newlines in the
              result. The elements of each record are formatted as usual  (via
              ::csv::join).

       ::csv::joinmatrix matrix {sepChar ,} {delChar "}
              Takes  a  matrix  object  following  the  API  specified for the
              struct::matrix package and returns a string in CSV  format  con-
              taining  these values. The separator character can be defined by
              the caller, but this is optional. The default is ",". The  quot-
              ing  character  can  be  defined  by  the  caller,  but  this is
              optional. The default is '"'. Each row of the matrix is  consid-
              ered  a  record,  these are separated by newlines in the result.
              The  elements  of  each  record  are  formatted  as  usual  (via
              ::csv::join).

       ::csv::read2matrix ?-alternate? chan m {sepChar ,} {expand none}
              A  wrapper  around  ::csv::split2matrix (see below) reading CSV-
              formatted lines from  the  specified  channel  (until  EOF)  and
              adding  them  to  the  given  matrix.  For an explanation of the
              expand argument see ::csv::split2matrix.

       ::csv::read2queue ?-alternate? chan q {sepChar ,}
              A wrapper around ::csv::split2queue (see below) reading CSV-for-
              matted  lines  from the specified channel (until EOF) and adding
              them to the given queue.

       ::csv::report cmd matrix ?chan?
              A report command which can be used by the matrix methods  format
              2string  and format 2chan. For the latter this command delegates
              the work to ::csv::writematrix. cmd is  expected  to  be  either
              printmatrix  or printmatrix2channel. The channel argument, chan,
              has to be present for the latter and must not be present for the
              first.

       ::csv::split ?-alternate? line {sepChar ,} {delChar "}
              converts  a  line  in  CSV format into a list of the values con-
              tained in the line. The character used to  separate  the  values
              from  each  other can be defined by the caller, via sepChar, but
              this is optional. The default is ",". The quoting character  can
              be  defined  by the caller, but this is optional. The default is
              '"'.

              If the option -alternate is specified a slightly different  syn-
              tax  is used to parse the input. This syntax is explained below,
              in the section FORMAT.

       ::csv::split2matrix ?-alternate? m line {sepChar ,} {expand none}
              The same as ::csv::split, but appends the resulting  list  as  a



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csv(n)                    CSV processing                   csv(n)


              new row to the matrix m, using the method add row. The expansion
              mode specified via expand determines how the command  handles  a
              matrix  with  less  columns  than contained in line. The allowed
              modes are:

              none   This is the default mode. In this mode it is the  respon-
                     sibility  of  the  caller  to  ensure that the matrix has
                     enough columns to contain the full line. If there are not
                     enough  columns  the list of values is silently truncated
                     at the end to fit.

              empty  In this mode the command expands an empty matrix to  hold
                     all  columns  of the specified line, but goes no further.
                     The overall effect is that the first of a series of lines
                     determines  the  number  of columns in the matrix and all
                     following lines are truncated to that size,  as  if  mode
                     none was set.

              auto   In  this mode the command expands the matrix as needed to
                     hold all columns contained in line. The overall effect is
                     that  after adding a series of lines the matrix will have
                     enough columns to hold all columns of  the  longest  line
                     encountered so far.

       ::csv::split2queue ?-alternate? q line {sepChar ,}
              The  same as ::csv::split, but appending the resulting list as a
              single item to the queue q, using the method put.

       ::csv::writematrix m chan {sepChar ,} {delChar "}
              A wrapper around ::csv::join taking all rows in the matrix m and
              writing them CSV formatted into the channel chan.

       ::csv::writequeue q chan {sepChar ,} {delChar "}
              A  wrapper  around  ::csv::join  taking all items in the queue q
              (assumes that they are lists) and  writing  them  CSV  formatted
              into the channel chan.


FORMAT
       The format of regular CSV files is specified as

       [1]    Each  record  of a csv file (comma-separated values, as exported
              e.g. by Excel) is a set of ASCII values separated  by  ",".  For
              other  languages  it  may  be  ";" however, although this is not
              important for this case as the functions provided here allow any
              separator character.

       [2]    If  and  only if a value contains itself the separator ",", then
              it (the value) has to be put between "". If the value  does  not
              contain the separator character then quoting is optional.

       [3]    If  a  value  contains the character ", that character is repre-
              sented by "".




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csv(n)                    CSV processing                   csv(n)


       [4]    The output string "" represents the value ". In other words,  it
              is  assumed  that  it  was created through rule 3, and only this
              rule, i.e. that the value was not quoted.


       An alternate format definition mainly used  by  MS  products  specifies
       that  the  output string "" is a representation of the empty string. In
       other words, it is assumed that the output was  generated  out  of  the
       empty  string by quoting it (i.e. rule 2), and not through rule 3. This
       is the only difference between the regular and the alternate format.

       The alternate format is activated through specification of  the  option
       -alternate to the various split commands.

EXAMPLE
       Using the regular format the record


       123,"123,521.2","Mary says ""Hello, I am Mary""",""


       is parsed into the items


       a) 123
       b) 123,521.2
       c) Mary says "Hello, I am Mary"
       d) (the empty string)


       Using the alternate format the result is


       a) 123
       b) 123,521.2
       c) Mary says "Hello, I am Mary"
       d) "

       instead.  As can be seen only item (d) is different, now a " instead of
       the empty string.

BUGS, IDEAS, FEEDBACK
       This document, and the package it describes, will  undoubtedly  contain
       bugs and other problems.  Please report such in the category csv of the
       Tcllib  SF  Trackers  [http://sourceforge.net/tracker/?group_id=12883].
       Please  also  report any ideas for enhancements you may have for either
       package and/or documentation.

SEE ALSO
       matrix, queue

KEYWORDS
       csv, matrix, package, queue, tcllib




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csv(n)                    CSV processing                   csv(n)


CATEGORY
       Text processing

COPYRIGHT
       Copyright (c) 2002-2008 Andreas Kupries <andreas_kupries@users.sourceforge.net>




















































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