.-
help for ^circxsm^
.-

Smoothing including lowess for circular data, x-variable circular
-----------------------------------------------------------------

    ^circxsm^ yvar xvar [^if^ exp] [^in^ range] [ ^, p^ad^(^#^)^
    ksm_options ]

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

^circxsm^ carries out smoothing (including lowess) for yvar with respect
to xvar. It is applicable when xvar is a circular variable taking on
values between 0 and 360 degrees. In this case, smoothed values just
above 0 degrees should take account of data just below 360 degrees, and
correspondingly just below 360 degrees. This is achieved by wrapping
data around.

The central 360 degree band contains smoothed values that take account
of data before and after 360 degrees. It may be marked off graphically
by ^xli(0,360)^. Outside this band, data are only used temporarily.

Options
-------

^pad(^#^)^ specifies a pad of # degrees at each x-axis end. Data less
    than or equal to # degrees are copied at the right end of the x-axis
    for an interval of 360 to 360+# degrees. Data more than 360-#
    degrees are copied at the left end of the x-axis for an interval of
    -# to 0 degrees. The default is 180, so that a full two cycles are
    shown.

ksm_options are any of the options allowed with ^ksm^; see help for
   ^ksm^.

It is the user's responsibility to see that the argument of ^pad^ is
consistent with the requested argument of ^bw^. The default is thought
to be safe.

Examples
--------

        . ^circxsm length wallasp, gen(lowessl) lowess^


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


Also see
--------

On-line: help for @ksm@, @graph@, @circplot@, @circnpde@, @circysm@

