Loading a variable from deferent .mat files selected using GUI matlab

how can i load a double from a mat file that i selected using push button in gui matlab , whatever the matfile i be able to extract an load a double from it and use it ex: i have a mat file called 1.mat and another 2.mat

 whos -file 1.mat
  Name                   Size             Bytes  Class     Attributes

X1RPM                1x1                  8  double              
X1_BA_time      122136x1             977088  double              
X1_DE_time      122136x1             977088  double              
X1_FE_time      122136x1             977088  double

dt=new.X1_DE_time;

 2nd mat file 2.mat

 whos -file 2.mat
  Name                   Size             Bytes  Class     Attributes

X2RPM                1x1                  8  double              
X2_BA_time      122136x1             977088  double              
X2_DE_time      122136x1             977088  double              
X2_FE_time      122136x1             977088  double

dt=new.X2_DE_time;

using GUI now 1st push putton

function Data_Callback(~, ~, handles)
[filename, pathname] = uigetfile({'*.mat'},'File Selector');
set(handles.text5,'String', filename)% showing full path name
handles.data=load([pathname, filename]);
data=filename;
setappdata(0,'data',data);

2nd push putton

function ok_Callback(hObject, eventdata, handles)
new=load(getappdata(0,'data'));

now i have the problem , how can i load de time whatever the mat file selected

dt=new.X1 or X2 or,...._DE_time;

[Stephen23]

Note that you should use fullfile instead of concatenating pathname and filename. You also need to pass pathname to the 2nd callback, otherwise your code will simply ignore the path that the user selects.

Note that this is a good example of why changing variable names inside .mat files is a bad idea: it makes accessing the data more difficult. It is actually much easier to access data in a loop, if all .mat files contains exactly the same variable names. Then this entire problem simply goes away.

And of course having lots of different variable names is a bad way to write code:

https://www.mathworks.com/matlabcentral/answers/304528-tutorial-why-variables-should-not-be-named-dynamically-eval

Answer 1

[Stephen23]

>> new.X1_BA_time = 1:3;
>> new.X1_DE_time = 4:6;
>> new.X1_FE_time = 7:9;
>> C = fieldnames(new);
>> X = cellfun('isempty',regexp(C,'^X\d+_DE_time$'));
>> dt = new.(C{~X})
dt =
   4   5   6

[BOULKROUNE RAMZI]

Tnk'x a lot Stephen for your help

[Stephen23]

@BOULKROUNE RAMZI: you are very welcome! Remember to accept my answer if it helped you.