.-
help for ^histplot^
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Histogram for frequency distribution
------------------------------------

    ^histplot^ varname [^if^ exp] [^in^ range] [weight]
    [^, w^idth^(^#^) by(^byvar^) fr^ac ^join u^linc
    barplot_options ]

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

^histplot^ plots a histogram showing the frequency distribution of
varname. The range of varname is divided into bins or classes of width
given by ^width( )^ and the limits of each class are multiples of that
width.

The default convention can be explained by example: if mpg varies from
12 to 41 miles per gallon, and width is 2, the classes will be by default
12 to almost 14, 14 to almost 16, ... , 40 to almost 42. In general,
each frequency is the number >= the lower limit and < the upper limit of
each class. The opposite convention is obtained by using the ^ulinc^
option.

aweights, fweights and iweights are allowed.

Options
-------

^width(^#^)^ specifies the width of each class. The default is
    ^width(0)^, meaning that the data are treated as they are.

^by(^byvar^)^ specifies that histograms are to be drawn separately
    for distinct values of byvar.

^frac^ specifies that frequencies are to be displayed as fractions of
    the total rather than as counts. Note that the default behaviour of
    ^histplot^ is the opposite of ^graph, histogram^, which shows
    fractions unless ^freq^ is specified.

^join^ means that histogram bars should be joined together by a
    base line.

^ulinc^ specifies that the upper limits are to be inclusive. In the
    example above, they would run from just above 10 to 12, and so on.
    In general, each frequency is the number > the lower limit and <=
    the upper limit of each class.

barplot_options are options of ^barplot^, other than ^sepbars^, which is
    chosen by default.


Remarks
-------

    ^histplot^ is a driver for ^genfreq^ and ^barplot^, which must be
    installed.


Examples
--------

        . ^histplot mpg, w(2)^
        . ^histplot mpg, w(2) l2(Fraction) yla frac^


Author
------

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


Also see
--------

On-line: help for @graph@, @barplot@ (if installed), @genfreq@ (if
         installed)

