how to plot 3D using a txt file

I want the following graph

I tried using mesh and surf it is showing error that data should be matrix not scalar my txt file is attached below please help me solve this

[Steve Eddins]

I can't figure out how the numbers in chalitp.txt correspond to the graph you are trying to make. Can you clarify what the numbers in the file mean? Which numbers are supposed to the surface height?

>> load chalitp.txt
>> chalitp

chalitp =

   45.0000   90.0000  106.7730    0.9351    0.8177
   90.0000   90.0000   99.4950    0.8714    0.6616
   54.7356  -45.0000   97.6599    0.8553    0.6257
   90.0000   45.0000   97.3437    0.8525    0.6196
   65.9052   63.4349   99.3358    0.8700    0.6584
   25.2394  -45.0000  101.6240    0.8900    0.7050
   25.2394   45.0000  102.7843    0.9002    0.7294
   90.0000   45.0000  102.8373    0.9006    0.7306
   65.9052   26.5651  111.1650    0.9736    0.9228
   11.4218  -45.0000  114.1827    1.0000    1.0000

[Nagendra Kamath]

first column is theta

second one is phi

third is Ds

I wanted plot of theta vs phi vs Ds

Answer 1

[Ameer Hamza]

I assume that first 3 columns are x, y, and z values. You need to use scatteredInterpolant

data = readmatrix('chalitp.txt');

x = data(:,1);
y = data(:,2);
z = data(:,3);

f = scatteredInterpolant(x, y, z);

xg = linspace(min(x), max(x), 20);
yg = linspace(min(y), max(y), 20);
[Xg, Yg] = meshgrid(xg, yg);
Zg = f(Xg, Yg);

surf(Xg, Yg, Zg);

[Nagendra Kamath]

Thank you it worked

[Ameer Hamza]

I am glad to be of help!!!