How to plot a pcolor from 3 vectors?

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Alex
Alex on 25 Apr 2017
Commented: Alex on 26 Apr 2017
I have 3 vectors that I imported from a text file in a three column format that I cannot change. The columns are latitude, longitude and temperature. I want to plot a 2D map with the temperature as a colorbar. Normally I use:
pcolor(lat,lon,temp), shading 'flat';%pcolor/mesh/surf(X,Y,Z)
But this only works when there is a value for every value of lat and lon; Z is a matrix. The values for lat and lon from my new source are scattered and at random intervals. Any suggestions, please?
Cheers,
Alex

Answers (1)

KSSV
KSSV on 26 Apr 2017
doc griddata
N = 1000 ;
x = 2*rand(N,1) - 1;
y = 2*rand(N,1) - 1;
z = 2*rand(N,1) - 1;
v = x.^2 + y.^3 - z.^4;
%
d = -1:0.05:1;
[xq,yq,zq] = meshgrid(d,d,0);
% Interpolate the scattered data on the grid. Plot the results.
vq = griddata(x,y,z,v,xq,yq,zq);
plot3(x,y,v,'ro')
hold on
surf(xq,yq,vq)
  1 Comment
Alex
Alex on 26 Apr 2017
Something is the matter with: vq = griddata(x,y,z,v,xq,yq,zq); ??? Error using ==> griddata at 53 XI and YI must be the same size or vectors of different orientations. I am guessing a ' is missing somewhere. For the moment, I am using:
pointsize = 10;
figure, scatter(data(:,1),data(:,2), pointsize, data(:,3))

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