Tkinter label textvariable not changing

Question

I read 4 entry boxes and store them as 4 elements of a matrix (numpy), then when a button is clicked, a function (convert) runs and a matrix is stored in z (z is declared as glo

Answer 1

You can't use a normal variable as a textvariable. It must be an instance of one of the special tkinter variables (eg: StringVar). To cause the label to update you could then call the set method of that variable.