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help for circrplot
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Raw data plot for circular data with spikes

        circrplot varname [if exp] [in range] [, clabel(label_specification)
                 ctick(numlist) resultant(resultant_options) round(#)
                 ticklength(#) twoway_options ]


Description 

    circrplot produces a raw data plot for varname with spikes showing
    frequencies. varname should be a circular variable taking on values
    between 0 and 360 degrees.

    Strictly, the values of varname are rounded to the nearest degree, or to
    the argument of round(). Spikes are drawn outwards from the circumference
    of a circle pointing in each direction present in the data. The length of
    each spike is proportional to the frequency of that direction. The
    resultant or mean direction is indicated by an arrow from the centre of
    the circle with length the radius of the circle X the vector strength.
    Hence an arrow representing a mean direction with vector strength 1 would
    touch the circle.

    The graph will usually best be shown with xsize() and ysize() equal, or
    nearly so. It may be helpful to know that the centre of the circle is at
    x = 0, y = 0 and that it has radius 1, so that the cardinal points North,
    East, South, West are at 0,1; 1,0; 0,-1; -1,0.


Options 

    clabel() specifies labels to be shown inside the circle at angles
        measured clockwise from 0 (North) through 360 degrees. Single text
        labels may be specified within " " following each label. For example,
        the default is clabel(0 "N" 90 "E" 180 "S" 270 "W").

    ctick() specifies positions of ticks to be shown inside the circle at
        angles measured clockwise from 0 (North) through 360 degrees.

    resultant() specifies options controlling the rendering of the arrow
        showing the resultant. In particular, arrowheadlength() specifies the
        arrowhead length (default 0.1).  Otherwise, such options are
        typically appropriate connect_options.

    round() indicates the bin or class width to be used (default 1 deg).

    ticklength() specifies the tick length (default 0.05).

    twoway_options are options of twoway.  By default the subtitle()
        indicates the mean direction and vector strength and is at pos(6).
        Note that the degree symbol can be specified by `=char(176)'.


Example 

    . circrplot wallasp, text(-0.5 0 "Wall aspect", size(large))
    . graph display, xsize(4) ysize(4)


Author

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


Also see

    On-line: help for circdplot (if installed), circvplot (if installed)