how to read multiple mat files and and extract data from those

I have a multiple .mat files (like 100 file) I need to load and extract specific data from those files. I.e to extract the row and columns so can anyone please help me out in this.

[Kevin Chng]

mat = dir('*.mat'); 
for q = 1:length(mat) 
load(mat(q).name); 
end

Hi, i see there is answer in https://www.mathworks.com/matlabcentral/answers/139879-how-to-read-all-mat-files-from-a-folder-in-matlab

However, you are mentioning you want to extract specific data from those files. As per my knowledge, may be we need to know what is the name of variable in the mat file first.

May be you can attach few of your mat file, and further elaborate it. So may be some of expert here can try it out.

[OriAlpha]

hello, has I mentioned above I have these type .mat files (like 150 files). i have to load all those files and have to extract column 11 in this all mat files and save it in one .mat file

i have attached few files below

Answer 1

[Kevin Chng]

Hi Suhas Goravale Siddaramu,

I have tried out your attached mat. file. I guess you are saying row 11 instead of column 11. In your mat.file, there is variable Pre-cell, it has 3 columns and 14 rows.

mat = dir('*.mat'); 
for q = 1:length(mat) 
load(mat(q).name); 
data(q,:) = Pre_cell(11,:)
end

with the additional line of code data(q,:) = Pre_cell(11,:), it will load all the row 11 of mat file into data.

Should you have any doubt, you may ask.

[OriAlpha]

Hello Freind, Has i asked above to extract data from files. We get 3 columns so that is my x, y, z-axis I need to plot those in 3D so how can I plot those

[Kevin Chng]

You may consider

plot3(data(:,1),data(:,2),data(:,3));
grid on
box on

Will it help you?

[OriAlpha]

Hello, I have another doubt

I have made a loop which loads all mat files in a folder then I have applied multiple functions for all the mat files and even the operation is going without errors and the last thing is that I have to save one loop value to one file.

like for 1 loop it should create 1 file

 for example if 200 loops it should create with 200 files with different names.
so how can i do it

[Madusha Sammani]

what is Pre_Cell

Answer 2

[ANKUR KUMAR]

Whenever you wish to load all files, just use dir.

F=dir('*.mat')
for i =1:length(F)
    load(F(i).name)
end

[Stephen Owino Omondi]

Awesome