function plot_iso(isodepths,pltlim,colorstr);
load c:\muse\auv\day\ryjo\wcoastline;
for N = 1:length(isodepths);
 idx = find(iso(:,depth)==-1*isodepths(N) &...
 iso(:,lat)>=pltlim(3) & iso(:,lat)<=pltlim(4) &...
 iso(:,lon)>=pltlim(1) & iso(:,lon)<=pltlim(2));
 q=plot(iso(idx,lon),iso(idx,lat),colorstr);set(q,'markersize',2);
end
