surf plot from text file

i have text with data an di dont know how to create a surface plot using surf function.

load('exportfilecst4.txt');

X = exportfilecst4(:,1);

Y = exportfilecst4(:,2);

z1 = exportfilecst4(:,4);

z2 = exportfilecst4(:,5);

z3 = exportfilecst4(:,6);

Z = z3;

plot3(X,Y,Z,'*','markerSize',3);

grid on

this is my code right now

i have attach the text file bellow

can anyone change it to surface plot

Answer 1

[Akira Agata]

Like this?

data = dlmread('exportfilecst4.txt');

x = data(:,1);
y = data(:,2);
z = data(:,6);

figure
surf(reshape(x,31,[]),reshape(y,31,[]),reshape(z,31,[]))

[Stephen23]

son nguyen xuan's incorrectly accepted "Answer" moved here:

oh thank you so much

[son nguyen xuan]

i'm sorry can you explain further how would you choose number 31? cause when i apply the code to another file, it can not produce a result

thank you

[Akira Agata]

Hi son nguyen xuan-san,

This is because, looking at your data, x (=> 1st column) value repeats 31 times.

[형섭 김]

hi , nice to meet you.

This is Hyoung Sup Kim from Korea.

Can I ask a question about reshape function?

I applied your command for my project.

But, it didn't work.

I will attach my data.txt file.

Please correct your code.

Thanks

From hskim

[Akira Agata]

Hi @형섭 김-san,

Looking at your data file, column-1 and -2 ware not sorted (I'm not sure why the data was saved in this order...).

Anyway, you can do the same thing by sorting the data, like:

% Read data file
D = readmatrix('uniformity_raw_1108_1118_7.56percent.txt',...
  'Delimiter','\t\t');

% Sort the data
D = sortrows(D,[1 2]);

% Reshape to make grid-style data array
xGrid = reshape(D(:,1),5,[]);
yGrid = reshape(D(:,2),5,[]);
zGrid = reshape(D(:,3),5,[]);

% Visualize the data
figure
surf(xGrid, yGrid, zGrid)

[형섭 김]

Dear Akira

Thank you for your kindly advice.

I have question.

I didn't recognize your feedback until I access matlab site.

How can I check your feedback immediately?

From hskim

[Walter Roberson]

@형섭 김

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