Error in XData=get(​get(gca,'c​hildren'),​'XData)

Hie guys, i have an error with the command above.

XData=get(get(gca,'children'),'XData');

YData=get(get(gca,'children'),'YData');

y_BPFO = interp1(XData,YData,BPFO);

I used this codes in my GUI. It works well when i have 1 axes in my GUI. But when i have 2 axes, it prompt me this error log,

??? Error using ==> interp1 at 121

X must be a vector.

Error in ==> maingui>updateAxes at 130

y_BPFO = interp1(XData,YData,BPFO);

Error in ==> gui_mainfcn at 96

        feval(varargin{:});

Error in ==> maingui at 42

    gui_mainfcn(gui_State, varargin{:});

??? Error while evaluating uicontrol Callback

Answer 1

[Paulo Silva]

Instead of gca you should use the handle for the axes that contains the data you want.

If you really want to use gca you can choose what's the current axes before, example:

axes(handles.axes2);

Your code doesn't ensure that there are children and that they contain useful data for interp1.

[Ean Soo]

XData=get(get(gca,'children'),'XData');

Can i know how to choose the axes im using with the command above.

Thanks

[Paulo Silva]

I assume you are using guide, first find out the name of the axe (axesX) you want to get data from and replace gca by handles.axesX where axesX is the name of your axes. If you are not using guide replace gca by the handle of the axe.

[Ean Soo]

Hie there, can i know if this command correct?

y=get(handles.axes3,'ylim');

plot(handles.axes3,[BPFI BPFI],y,'-r');

[Paulo Silva]

y=get(handles.axes3,'ylim');

axes(handles.axes3); %make axes3 the current axes

line([BPFI BPFI],y,'LineStyle','--','Color',[1 0 0]) %draw the line