Mar-11-2018, 06:14 PM
(This post was last modified: Mar-11-2018, 06:14 PM by TheRedFedora.)
Hello everyone,
I had the plan to make a calculator for my schoolproject. Everything I did seemed fine until the point that I actually ran the whole thing. Then the error occurred.
*Quick edit, the GUI is working, the error occurres after I put in my first variable and press on any of the options from equate. Then it doesn't type numbers anymore and gives an error when I hit the "="
TheRedFedora
I had the plan to make a calculator for my schoolproject. Everything I did seemed fine until the point that I actually ran the whole thing. Then the error occurred.
Error:line 33, in equate
self.result = float(self.var1) - float(self.var2)
ValueError: could not convert string to float:
this is my code: from tkinter import * master = Tk() display = Entry(master, width=20, justify='right', bd=0, bg='lightgrey') master.title("calculator") class Calculator: def __init__ (self): self.var1 = "" self.var2 = "" self.result = 0 self.current = 0 self.operator = 0 def number_button(self, index): if self.current is 0: self.var1 = str(self.var1) + str(index) display.delete(0, END) display.insert(0,string=self.var1) else: self.var1 = str(self.var2) + str(index) display.delete(0, END) display.insert(0, string=self.var2) def equate(self): if self.operator is 0: self.result = float(self.var1) + float(self.var2) elif self.operator is 1: self.result = float(self.var1) - float(self.var2) elif self.operator is 2: self.result = float(self.var1) * float(self.var2) elif self.operator is 3: self.result = float(self.var1) / float(self.var2) display.delete(0, END) display.insert(0, string=self.result) def set_op(self, op): self.operator = op display.delete(0, END) if self.current is 0: self.current = 1 else: self.equate() self.var2="" def clear(self): self.__init__() display.delete(0, END) calc = Calculator() b0 = Button(master, text="0", command=lambda: calc.number_button(0)) b1 = Button(master, text="1", command=lambda: calc.number_button(1)) b2 = Button(master, text="2", command=lambda: calc.number_button(2)) b3 = Button(master, text="3", command=lambda: calc.number_button(3)) b4 = Button(master, text="4", command=lambda: calc.number_button(4)) b5 = Button(master, text="5", command=lambda: calc.number_button(5)) b6 = Button(master, text="6", command=lambda: calc.number_button(6)) b7 = Button(master, text="7", command=lambda: calc.number_button(7)) b8 = Button(master, text="8", command=lambda: calc.number_button(8)) b9 = Button(master, text="9", command=lambda: calc.number_button(9)) b_dot = Button(master, text=".", command=lambda: calc.number_button(".")) plus = Button(master, text="+", command=lambda: calc.set_op(0)) minus = Button(master, text="-", command=lambda: calc.set_op(1)) times = Button(master, text="x", command=lambda: calc.set_op(2)) divide = Button(master, text="/", command=lambda: calc.set_op(3)) equals = Button (master, text="=", command=calc.equate) clear = Button (master, text="c", command=calc.clear) display.place(x=0, y=2) b7.grid(row=1, column=0) b8.grid(row=1, column=1) b9.grid(row=1, column=2) b4.grid(row=2, column=0) b5.grid(row=2, column=1) b6.grid(row=2, column=2) b1.grid(row=3, column=0) b2.grid(row=3, column=1) b3.grid(row=3, column=2) b0.grid(row=4, column=0) b_dot.grid(row=4, column=1) clear.grid(row=4, column=2) plus.grid(row=1, column=3) minus.grid(row=2, column=3) times.grid(row=3, column=3) divide.grid(row=4, column=3) equals.grid(row=4, column=3) master.mainloop()The problem seems to be coming out of the "equate" section. Is there a way to fix it or is there maybe an alternative code that would do the trick?
*Quick edit, the GUI is working, the error occurres after I put in my first variable and press on any of the options from equate. Then it doesn't type numbers anymore and gives an error when I hit the "="
TheRedFedora