# How to extract data from specific row

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Fouziah Yassin le 3 Jan 2023
Hi,
I am still new using MATLAB. For your information, I have the data at the workspace (40000 x 7 double) but how can I extract the data at the row with the value of the first column is 1 or 2? Thank you in advance.
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### Réponse acceptée

Bjorn Gustavsson le 3 Jan 2023
Modifié(e) : Bjorn Gustavsson le 3 Jan 2023
You can do things like this in matlab:
data_oi = data(data(:,1)==1|data(:,1)==2,:);
This wouild give you your data of interest in a variable data_oi where the elements in the first column is either a 1 or a 2. If you're this new to matlab, then one good recommendation is to browse through the on-ramp material - which is a introductory information presentation.
HTH
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Fouziah Yassin le 4 Jan 2023
Many thanks for the answer and it's really helpful. Really appreciate it. I tried it and understood how it worked.
Bjorn Gustavsson le 5 Jan 2023
My pleasure, happy that it helped.

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### Plus de réponses (1)

Mathieu NOE le 3 Jan 2023
If your data is A , the rows that contains 1 in the first column are defined by ind1
see example below
% dummy data
A = rand(10,10);
A(:,1) = randi(3,10,1);
% extract data when first column contain 1
ind1 = (A(:,1)==1); % logical index
A1 = A(ind1,:) % A extract for first column containing 1's
% extract data when first column contain 2
ind2 = (A(:,1)==2); % logical index
A2 = A(ind2,:) % A extract for first column containing 2's
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Fouziah Yassin le 4 Jan 2023
Thank you for the code with the explanation. It is really useful for me to learn.

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