function orca_vg_plot(VG,psize,cols)
%
% Call orca_kn_plot(KNR,KNI,cref,psize,cols)
% Plots modes in complex k-plane.
% KNR,KNR   = structures from hdfsd_read of ORCA .hdf file;
% cref	= reference sound speed for converting to cos(theta) (0=plot vs phase velocity);
% psize     = [width,height] of plot;
%
%
% COPYRIGHT (c) 2008
% 
% Applied Research Laboratories, The University of Texas at Austin
% (ARL:UT)
% All rights reserved.
% 
% This material may be reproduced by or for the U.S. Government
% only. This notice must appear in all copies of this file and its
% derivatives. Further distribution outside the U.S. Government is
% prohibited without the explicit written authorization from the
% Director of the Environmental Sciences Laboratory, ARL:UT.
% 
% THIS SOFTWARE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND,
% EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO THE
% IMPLIED WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
% PURPOSE, OR NONINFRINGEMENT.
% 
% IN NO EVENT WILL ARL:UT BE LIABLE FOR ANY DAMAGES WHATSOEVER ARISING
% OUT OF THE USE OR INABILITY TO USE THIS SOFTWARE, EVEN IF ARL:UT HAS
% BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
[nfreq,nm_max]=size(VG.data);
for jm=1:nm_max,
    iif=find(~isnan(VG.data(:,jm))); nfreq=length(iif);
    freqs=VG.scales{1}(iif);
    vg=VG.data(iif,jm); %vph=VPH.data(jfreq,iim);
% Plot:
    ncol=length(cols); jcol=mod(jm-1,ncol) + 1;
    h=plot_cfill(freqs,vg,'o',cols(jcol),5,'none',1.5,0);
    hold on;
end
%
xlabel('Frequency - Hz'); 
ylabel('Group Speed - m/s'); grid on;
plot_size(gca,'in',psize(1),psize(2));
plot_set3(gca,-1.5,'Arial',14,1);
zoom on;
