Undefined function or variable (Passing data between functions)

Hi, I got this problem. When storing data in a function and then I trying to retrieve it 'Undefined function or variable 'GI'' occurs.

This is the code in which I get the data from a GUI (It works well):

function [GI]=GUI_INP(hObject, eventdata)
%Get the handle of Input_parameters and Geometrical_characteristics
hfig_i_p = findobj('Tag','Initial_parameters');
%If exists (not empty)
if ~isempty(hfig_i_p)
       i_p=guidata(hfig_i_p);
       %ТТХ
       GI.Vpol=i_p.Vpol_value;     
       %Полетные параметры  
       GI.plotn=i_p.plotn_value; %плотность воздуха 
       else
       disp('INGRESE LOS DATOS EN I_P Y G_C');
end
end

And then the code in which I try to retrieve that data:

function [sys,Inp,geom_aircraft]=Z_INP(GI)
%ТТХ
Inp.Vpol=GI.Vpol;
%полетные параметры
Inp.plotn=GI.plotn; %плотность воздуха
end

I will aprecciate the help.

[Nicola Bombace]

If you try to run the file Z_INP.m , it will not know about the Variable GI. After you run the GUI gathering of your data simply use

[sys,Inp,geom_aircraft]=Z_INP(GI);

in a command line or a new script that could look like

[GI]=GUI_INP(hObject, eventdata);
[sys,Inp,geom_aircraft]=Z_INP(GI);

[Oscar Espinosa]

Those are the steps that I am taking, even though I get 'Undefined function or variable 'GI''. Both functions are located in the same path.

[Nicola Bombace]

The question would then be if you see the Variable GI in the workspace after you call the GUI_INP function. If the variable is not there is because this condition ~isempty(hfig_i_p) is false.

[Oscar Espinosa]

Is in the workspace while function executing, then just return ans with the values Vpol and plotn. If I try executing in the Command Window I got 'Undefined function or variable 'hObject''.

[Oscar Espinosa]

Thank for help, I found the problem. The function do not need hObject and eventdata.

function [GI]=GUI_INP(hObject, eventdata)

Answer 1

[Jan]

How do you call these functions?

GI = GUI_INP(hObject, eventdata);
[sys,Inp,geom_aircraft] = Z_INP(GI);

This should work. At least partially, because sys and geom_aircraft are still undefined.

The code will fail, when the wanted figure is not found. Better use error() with a clear message, instead of just a disp(), because the following code will fail with confusing messages.

If you have a lot of open figures containing many objects, this

hfig_i_p = findobj('Tag','Initial_parameters');

will take some time, because it compares the Tags of all GUI-elements. Specify the object type instead:

hfig_i_p = findobj(allchild(groot), 'flat', 'Tag', 'Initial_parameters', 'Type', 'Figure');

Currently this is redundant, because the children of groot are figures only. But maybe this will change in the future.

[Oscar Espinosa]

Actually I'm calling

[sys,Inp,geom_aircraft] = Z_INP(GI);

from another funtion. I'm doing this intermediate step between the data stored in a GUI and the function that needs that data because the function to execute have 8 input, and if I add the hObject, and evenData as 2 more arguments it just does not work.

This is the function which is calling:

function [Result,Inp,lz,nu,str,c_,f0,fk]=m(s_lz,s_nu,s_srt,s_ak,s_c,s_c_k_koef,s_f0,s_fk);
[lz,nu,str,ak,c_,c_k_koef,f0,fk]=INP(s_lz,s_nu,s_srt,s_ak,s_c,s_c_k_koef,s_f0,s_fk);
shet=1;
for s=1:length(lz)
Inp.lz=lz(shet,1);
Inp.nu=nu(shet,1);
Inp.str=str(shet,1);
Inp.a_k=ak(shet,1);
Inp.c_=c_(shet,1);
Inp.c_k_koef=c_k_koef(shet,1);
Inp.f_0=f0(shet,1);
Inp.f_k=fk(shet,1);
[sys,Inp,geom_aircraft]=Z_INP(GI);
...
end

[Oscar Espinosa]

Thank you by the help, I found the problem, posted it lines above. And I will keep in mind the advices that you gave me.