.-
help for ^tabplot6^
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Table of frequencies as one or more bar charts or histograms
------------------------------------------------------------

    ^tabplot6^ [rowvar] colvar [^if^ exp] [^in^ range] [weight]
    [ ^, colpr colfr colpc rowpr rowfr rowpc xasis yasis w^idth^(^#^)^
    ^z^ero graph_options ]

Description
-----------

^tabplot6^ plots a table of frequencies in graphical form. It is intended
for use when at least one of the variables shown is categorical.

^tabplot6^ colvar plots a vertical bar chart or histogram of the
frequencies of colvar. The frequencies are regarded as one row of a
multi-column table.

^tabplot6^ rowvar colvar plots the frequency of each combination of row
and column as an array of bars with height proportional to frequency,
that is, as a series of vertically stacked bar charts or histograms.

The bars are unshaded. By default they take up 50% of the horizontal
space: this may be varied directly by use of the ^width( )^ option. By
default both variables are mapped in sort order to successive integers
from 1 up, but original values are used as value labels: this may be
varied by use of the ^xasis^ or ^yasis^ options.

^tabplot6^ is a renamed version of ^tabplot^ 1.0.1 of 26 February 1999, 
written for Stata 6. Users of Stata 8 on would switch to ^tabplot^ 2.0.0 
or later. 


Remarks
-------

^tabplot6^ colvar differs from ^hist^:

    ^tabplot6^ allows the width of bars to be controlled, but not the
    shading. Thus bars may touch or not touch according to choice.
    ^hist^ behaves conversely, and bars always touch unless there are
    gaps in the data.

    ^tabplot6^, but not ^hist^, takes categorical variables coded as
    strings.

    ^hist^ always takes values literally.

    ^hist^ produces a maximum of 50 bins, whereas ^tabplot6^ is
    unlimited.

^tabplot6^ rowvar colvar, ^xasis^ may be useful for stacking histograms
    vertically. A typical protocol would be

    .^ gen Numvar = round(numvar, ^#^)^
    .^ _crcslbl Numvar numvar^
    .^ tabplot6 catvar Numvar, xasis w(^#^)^


Options
-------

^colpr^, ^colfr^, ^colpc^, ^rowpr^, ^rowfr^, ^rowpc^ scale frequencies
     to be proportions (fractions), adding to 1, or percents, adding to
     100, of each column or row total. ^colpr^ and ^colfr^ are
     numerically equivalent but the text produced on the graph will be
     ^proportion^ or ^fraction^ respectively: the same distinction
     applies to ^rowpr^ and ^rowfr^. The ^col^* options are useful only
     when two variables are plotted.

^width(^#^)^ specifies the widths of the bars. The default is
    ^width(0.5)^. This may need changing with option ^xasis^.

^xasis^ and ^yasis^ specify that the x (column) and y (row) variables
    are to be treated literally (that is, numerically). Most commonly,
    ^xasis^ will be specified if the x variable is a measured scale or a
    graded variable with gaps. If values 1 to 5 are labelled A to E, but
    no 4 (D) is present in the data, ^xasis^ prevents a mapping to 1 (A)
    ... 4 (E).

^zero^ specifies that zeros are to be shown explicitly by bars of
    zero height, shown in practice by a discernible line.

graph_options are options allowed with ^graph, twoway^, other than
    ^symbol^ and ^connect^, ^xlabel^ by itself and ^ylabel^ by itself.
    ^yreverse^ and ^yline( )^ may be useful. Note that these options do
    not include ^shading^. ^t1(" ")^ may be used to blank out the
    ^t1title( )^ that by default signals the maximum quantity plotted
    when two variables are specified.


Examples
--------

        . ^tabplot6 rep78^
        . ^tabplot6 for rep78^
        . ^tabplot6 for mpg, xasis w(1)^


Author
------

         Nicholas J. Cox, University of Durham, U.K.
         n.j.cox@@durham.ac.uk


Also see
--------

On-line: help for @graph@, @hist@, @histplot@ (if installed)