How can I plot x y and corresponding "z" point values discretely ( without creating surf or meshgrid or stem3) in 2d color coded image?

I have a database including long lat and number of damaged house for every coordinate point. How can I make a color coded plot to show a qualitative data distribution of the damage as high medium or low damage?

Answer 1

[Star Strider]

One option is bar3, depending on what you want to show, and how you want to show it.

I don’t have the Mapping Toolbox so I can’t help you with the lat-lon details.

Answer 2

[arich82]

Unless I'm misunderstanding your data, it seems like "scatter" should do what you want (just use your z-value of damage as the color input):

marker_sz = 50;
n = 1000;
x = 2*rand(n, 1) - 1;
y = 2*rand(n, 1) - 1;
z = x.^2 + y.^2;
figure;
scatter(x, y, marker_sz, z, 'o', 'filled');

You can play with "colorbar" and "colormap" for discrete damage values, e.g.

z = floor(2*sqrt(x.^2 + y.^2)); % gives z a value of 0, 1, or 2
figure;
scatter(x, y, marker_sz, z, 'o', 'filled');
colorbar;
R = [1, 0, 0]; 
Y = [1, 1, 0]; 
G = [0, 1, 0]; 
colormap([R; Y; G]); % 2-->green, 1-->yellow, 0-->red

Hope this helps.