How do you get "indexed contour" / thick contour at intervals among thin contours?

[rmt1]

Project: creating a topological map using contourf.
Problem: I'm trying to reproduce the example script on "indexed Contours"
from MatLab found on
<http://www.mathworks.com/help/matlab/creating_plots/contour-plots.html#f10-3467>
Whether I leave it graphics_toolkit ("gnuplot") or specify graphics_toolkit
("fltk"), both results have entirely uniformly thin contours - no contour
has any enhanced LineWidth. Ideas for what configuration I am missing? Thank
you.

z=peaks(100);
zmin=floor(min(z(:)));zmax=ceil(max(z(:)));
zinc=(zmax-zmin)/40;
zlevs=zmin:zinc:zmax;
zindex=1;
[c2,hc2]=contour(z,zlevs);
nc=get(hc2,'Children');
for i =1:length(nc)
ud=get(nc(i),'UserData');
if(mod(ud,zindex)==0)
set(nc(i),'LineWidth',2);
end
end



--
View this message in context: 
http://octave.1599824.n4.nabble.com/How-do-you-get-indexed-contour-thick-contour-at-intervals-among-thin-contours-tp4656807.html
Sent from the Octave - General mailing list archive at Nabble.com.