function floverl(x,y)
%
%   The function floverl(x,y) overlays a plot of the current float
%   on the pre-existing figure.  The beginning of the data 
%   (launching position is defined by a 'o', each data point is 
%   shown with '.', and every 'step' days with a cross.
%
%-------------------------------------------------------------------
%   Written by Vassilis Zervakis, in February 1996, while at
%              AINCO - Interocean, Madrid, Spain.
%
%   Modified by Mike Sparrow in October '97.
%-------------------------------------------------------------------
%
global mapfigure tjump
global flstep linecolor startsymbol startcolor
global stepsymbol stepcolor
%
figure(mapfigure);
flstep = flstep*tjump
linecolor = num2str(linecolor);
start = [startcolor startsymbol];
steps = [stepcolor stepsymbol];
colordot = [linecolor '.'];
isstr(colordot);
isstr(start);
isstr(steps);
hold on
kl = 1;
if flstep ~= 0.,
    for kk = 1:flstep:length(x)
      x1(kl) = x(kk); 
      y1(kl) = y(kk); 
      kl = kl + 1;
    end
    line('Xdata',x,'Ydata',y,'Color',linecolor,'Erasemode','none');
    line('Xdata',x(1),'Ydata',y(1),'Color',startcolor,'LineStyle',startsymbol,'Erasemode','none');
    line('Xdata',x1,'Ydata',y1,'Color',stepcolor,'LineStyle',stepsymbol,'Erasemode','none');
    clear x1;
    clear y1;
  else
    line('Xdata',x,'Ydata',y,'Color',linecolor,'Erasemode','none');
    line('Xdata',x(1),'Ydata',y(1),'Color',startcolor,'LineStyle',startsymbol,'Erasemode','none');
end
hold off;
end
