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

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)

Answer 1

[KSSV]

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)

[Prasad Joshi]

Thank you sir

[Prasad Joshi]

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]

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.

Answer 2

[KALYAN ACHARJYA]

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)

[Prasad Joshi]

Thanks Kalyan for your answer but i am looking to used 2D graph only specially Contour plot ..In 3D visulaization is not that good ....

[KALYAN ACHARJYA]

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.

[Prasad Joshi]

Thanks kalyan for your help