Why am I unable to specify a dashed line style for contour plots of large matrices in MATLAB 7.0 (R14)?

When I specify a dashed line style in the CONTOUR function in MATLAB 7.0 (R14) with a large input matrix, the resulting contour lines are not dashed. For example:

q=peaks(200);

contour(q,10,'--');

results in contour lines that are continuous rather than dashed.

Answer 1

[MathWorks Support Team]

The lines appear continuous due to the large number of data points. Zooming in far enough shows the dashed nature of the lines.

However, to work around this problem, switch the renderer of the parent figure to "zbuffer" or "OpenGL". For example:

q=peaks(200);

contour(q,10,'--');

set(gcf,'renderer','zbuffer');