function plotspec(SM,ptype);

%DIWASP V1.1 function
%plotspec: plots the spectral matrix in 3D or polar form
%
%plotspec(SM,ptype)
%
%Inputs:
% SM   		A spectral matrix structure
% ptype		plot type:
%   1	3D surface plot
%   2	polar type plot 
%   3	3D surface plot (compass bearing angles)
%   4	polar type plot   (compass bearing angles)
%
%The 3D surface plot type is a MATLAB surface plot with SM.freqs on the x axis, SM.dirs on the y axis and the spectral density, SM.S as the z value. 
%The polar type plot is a MATLAB polar plot with the direction showing values in SM.dirs, the radius showing values in SM.freqs 
%and contours representing the spectral density, SM.S. An example of the polar type plot is shown on the front cover of the manual.
%For both plot types, the direction is the direction of propagation (see also The DIWASP spectrum file format).  
%For options 3 and 4 the direction is the compass bearing. This is calculated from the SM.xaxisdir input that defines the orientation of the axes. 
%Note that if SM.xaxisdir is 90 the appearance of the polar plot is unchanged.
%
%"help data_structures" for information on the DIWASP data structures

%Copyright (C) 2002 Coastal Oceanography Group, CWR, UWA, Perth

fig=figure;

SM=check_data(SM,2);if isempty(SM) return;end;
dirs=SM.dirs;ffreqs=SM.freqs;S=real(SM.S);

if (ptype==3|ptype==4)
      xaxisdir=SM.xaxisdir;
      if ~(xaxisdir >=0 & xaxisdir <=360)
         warning('xaxisdir must be between 0 and 360 -set to default value of 90');
         xaxisdir=90;
      end   
end

if(ptype==1|ptype==3)
      if(ptype==3)
      	dirs=xaxisdir*ones(size(dirs))-dirs;
         dirs=dirs+360*(dirs<0);
         dirs=dirs-360*(dirs>360);
      	[dirs,order]=sort(dirs);
   	else
         order=([1:max(size(dirs))]);
      end
   [ddir,df]=meshgrid(dirs,ffreqs);
   surf(df,ddir,real(S(:,order)));
   
   shading interp;
   xlabel('frequency [Hz]');
   if(ptype==1)
      ylabel('direction [degrees]');
      axis([0 (max(ffreqs)) -180 180 0 (max(max(S)))]);

   else
      ylabel('direction [bearing]');
      axis([0 (max(ffreqs)) 0 360 0 (max(max(S)))]);
   end
   zlabel('m^2s / deg');
   
elseif(ptype==2|ptype==4)
   if(ptype==4)
      dirs=(90-xaxisdir)*ones(size(dirs))+dirs;
   end
   h = polar([0 2*pi], [0 0.4]); %[0 0.8*max(ffreqs)]);  Changed on 5/25
   delete(h);
   
   [df,ddir]=meshgrid(ffreqs,dirs);
   
%uses the existing polar figure function and replaces numbering of angles for compass directions. Will probably be changed in future versions.
	if(ptype==4)
   set(0,'ShowHiddenHandles','on')
   chhs=get(gca,'Children');
   for i=1:size(chhs,1);
      obj=chhs(i);
      if strcmp(get(obj,'Type'),'text')
         num=str2num(get(obj,'String'));
         if~(isempty(num))
         if mod(num,30)==0
            num=90-num;
            num=(num<0)*360+num;
            set(obj,'String',num2str(num));
         end
         end
      end
   end
   set(0,'ShowHiddenHandles','off')
   end
         
   hold on;
    
	[px,py]=pol2cart(ddir*pi/180,df);
	contour(px,py,real(S'),20);

   caxis([0 max(max(S))]);
   colorbar('vert');
   if(ptype==2)
      ylabel('direction [degrees] / frequency [Hz]');
   else
      ylabel('direction [bearing] / frequency [Hz]');
   end
	xlabel('m^2s / deg');
   hold off;
end

set(gca,'Color','none');