MATLAB: Need better resolution in the plot!

matrix plotpcolorplotresolution

Hello,

I am working on a plot of a local density of states and want to know if anyone has any suggestions to improve the resolution.

Basically, all I am doing is taking a matrix of values and plotting these magnitudes on a lattice. The function I am doing to do this plot is pcolor, which I understand may not be the best choice. I am just not sure how to plot a matrix with a different function. If anyone knows of a better function or how to improve pcolor's resolution, it'd be greatly appreciated!

Attached are the relevant programs. I tried attaching the parameters complied from BdG, but they were too large even after zipping. I set the number of lattice sites N=60, so it does not take too long to compile (note this will affect the resolution but not terribly bad). Run example after the workspace has the relevant parameters loaded.

Any help will be greatly appreciated! Thanks.

Best Answer

I'm a bit confused. I still have no idea which bits of code are relevant. Still can't run example.m and I'm unclear what to to do with the outputs of BdG_Hamiltonian. As for your figure, it contains an Image object in the axis whereas pcolor creates a Surface object.

It looks like you used imagesc, not pcolor. Anyway, as I wrote pcolor, imagesc, etc. do not do any interpolation. They plot exactly the number of points you give them. However, it's trivial for you to rescale your original matrix to a higher resolution:

%get the cdata out of plot_of_LDOS.fig since we don't have the original data:
hfig = openfig('plot_of_LDOS.fig');
source = hfig.Children.Children.CData;  %Children of figure is the axis, children of the axis is the image
%plot at higher resolution
figure; 
imagesc(imresize(source, 8))

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