Getting following error while making Contourf plot [ Error using contourf Z must be at least a 2x2 matrix]

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I am getting this error while making contour plot [ Error using contourf (Z must be at least a 2x2 matrix]. can someone please help how can i make an contour plot and also i wanted to add z data on it . I am basically looking for following contour plot. can someone please help how can i do it . Thanks in advance
clear all
close all
clc
[num,txt,raw] = xlsread('Book1.xlsx') ;
X = num(:,1) ;
Y = num(:,2) ;
Z = num(:,3) ;
figure(1)
contourf(X,Y,Z)

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KSSV
KSSV il 8 Nov 2022
T = readtable('https://in.mathworks.com/matlabcentral/answers/uploaded_files/1185378/Book1.xlsx') ;
x = T.(1) ;
y = T.(2) ;
z = T.(3) ;
m = 50 ; n = 50 ;
xi = linspace(min(x),max(x),m) ;
yi = linspace(min(y),max(y),n) ;
[X,Y] = meshgrid(xi,yi) ;
Z = griddata(x,y,z,X,Y) ;
contourf(X,Y,Z)
  3 Commenti
Prasad Joshi
Prasad Joshi il 9 Nov 2022
Thank you sir for answer but But is it possible to get the full range of plot as shown in the below figure ..Thanks in advance
KSSV
KSSV il 9 Nov 2022
You will get the data for the region which is covered by the scattered points. If you want it outisde you need to go for extrapolation; which is not suggested. However you can fix a constant value if you are aware of the data. Read the documentation part with extrapolation option.

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KALYAN ACHARJYA
KALYAN ACHARJYA il 8 Nov 2022
Modificato: KALYAN ACHARJYA il 8 Nov 2022
You may be look for other data visulization options, as its a 3 column data e.g
stem3, scatter3 or plot3
In mesh, surface, contour, Z much needed as as matrix (where respective valuses are assigned in grid plane)
  3 Commenti
KALYAN ACHARJYA
KALYAN ACHARJYA il 8 Nov 2022
Can you try using pen and paper to do data visualization in your case (3 column data)? Those surface plots need to have a grid plane/values.

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