How to read a txt file in matlab?

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EcoBase
EcoBase on 30 Aug 2018
Commented: EcoBase on 31 Aug 2018
I'm completely new to Matlab, so my question may sound dumb! I apologize. I'm trying to open a txt file in Matlab and produce a colormap with the data in the file. But it seems like Matlab doesn't read the file correctly. I attached the file for your reference. I used 'importdata' function. It should look like
but every time I import the data, it shows something like this:
Can anyone please help me? Thank you so much in advance
  3 Comments
EcoBase
EcoBase on 30 Aug 2018
Edited: Stephen23 on 30 Aug 2018
Oops!! I'm so sorry, I attached a wrong one. Please check the new file attached. (The file is too large, so I pasted only a few rows from the original one). What I'm trying to do is the same as this approach - https://kr.mathworks.com/matlabcentral/answers/337686-how-to-create-an-image-from-txt-file
The file contains x, y coordinates of an image and relevant value for each pixel. Thank you.
EcoBase
EcoBase on 31 Aug 2018
I uploaded two original files and shared in links below: https://drive.google.com/open?id=1utfXBqnRgjv6AIl_dSor-amooxk3-QwQ
https://drive.google.com/open?id=12NGdhO6xZ1525IkjLUhIHEKjSxbgGy1o
I'd really appreciate it if you could check and help me with the problem! Thank you.

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Accepted Answer

KSSV
KSSV on 30 Aug 2018
data = importdata('data.txt') ;
x = data(:,1) ; y = data(:,2) ; z = data(:,3) ;
plot3(x,y,z) ; % with the present data
% If you want a surf plot and data is full
% surf
N = 100 ;
xi = linspace(min(x),max(x),N) ;
yi = linspace(min(y),max(y),N) ;
[X,Y] = meshgrid(xi,yi) ;
F = scatteredInterpolant(x,y,z,'linear','none') ;
Z = reshape(F(X(:),Y(:)),N,N) ;
figure
pcolor(X,Y,Z)
  4 Comments
EcoBase
EcoBase on 30 Aug 2018
It says 'scatteredInterpolant' isn't a valid extrapolation type. Here are links for the file in two different format (text and excel). Thank you so much.
https://drive.google.com/open?id=1utfXBqnRgjv6AIl_dSor-amooxk3-QwQ
https://drive.google.com/open?id=12NGdhO6xZ1525IkjLUhIHEKjSxbgGy1o
EcoBase
EcoBase on 31 Aug 2018
Could decimals in Z axis matter? When I tried with other files containing only integers, it seemed to be working okay. I could produce an image in the way I wanted.

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