Question

This is part of the code I’m using – problem is detailed below. I am creating a simple savings calculator using Python 3.2 and tkinter on Mint Linux Nadia. Advice welcome!
Thanks
Tom

    Button(self,
           text = "Click for savings calculations",
           command = self.show_result
           ).grid(row = 6, column = 0, sticky = W)

    self.result_txt = Text(self, width = 75, height = 10, wrap = WORD)
    self.result_txt.grid(row = 7, column = 0, columnspan = 4)

def show_result(self):

    curacct = int(self.curacct_ent.get())

    isa = int(self.isa_ent.get())

    av = int(self.av_ent.get())
    avu = int(self.avu_ent.get())

    a = int(curacct + isa)
    b = int(av*avu)



    result = "Your savings total is £", (a)
    result += "and the A shares are worth £", (b)
    result += "Your total savings is £", (a+b)





    self.result_txt.delete(0.0, END)
    self.result_txt.insert(0.0, result)

# main
root = Tk()
root.title("Savings Calculator")
app = Application(root)
root.mainloop()

When I run the program the text prints fine, however it contains curly braces around the text:
{Your savings total is £} 10 {and the A shares are worth £} 25 {Your total savings is £} 35

I can’t understand why there are curly braces, but I want them gone. Does anyone know how I can do this? BTW I’m just an enthusiast learning python and loving it so far. I’ve only included the section of the code that I think is relevant.

Answer 1

With

result = "Your savings total is £", (a)

you are creating a 2-element tuple (“Your savings total is £”, a).

Then you add new elements to the tuple with += operator.

result_txt.insert expects a string as a second argument, not a tuple (docs), so you want to use string formatting instead:

result = ("Your savings total is £{} "
          "and the A shares are worth £{} "
          "Your total savings is £{}").format(a, b, a+b)

(see Python docs explaining format)