I'm trying to program my calculator project to perform operations. It can perform addition and I want it to perform the remaining four (minus, multiplication, division, powers) But I'm stuck because of this error:
C:\Users\Admin\PycharmProjects\venv\Scripts\python.exe
"C:/Users/Admin/PycharmProjects/pythonProject/Calculator GUI v1.0.py"
Exception in Tkinter callback
Traceback (most recent call last):
File "C:\Users\Admin\Python3.9\lib\tkinter\__init__.py", line 1892, in __call__
return self.func(*args)
File "C:\Users\Admin\PycharmProjects\pythonProject\Calculator GUI v1.0.py", line 32, in
button_subtract
e.insert(0, f_num + int(second_number))
NameError: name 'f_num' is not defined
Process finished with exit code 0
My code:
import tkinter as Tk
from tkinter import *
root_var = Tk()
root_var.title("Calculator")
e = Entry(root_var, width=25, borderwidth=5)
e.grid(row=0, column=0, columnspan=3, padx=10, pady=10)
def button_click(number=None):
#e.delete(0, END)
current = e.get()
e.delete(0, END)
e.insert(0, str(current) + str(number) )
def button_clear():
e.delete(0, END)
def button_add():
first_number = e.get()
global f_num
f_num = int(first_number)
e.delete(0, END)
def button_subtract():
second_number = e.get()
e.delete(0, END)
e.insert(0, f_num + int(second_number))
def button_multiply():
third_number = e.get()
e.delete(0, END)
e.insert(0, f_num + int(third_number))
def button_divide():
fourth_number = e.get()
e.delete(0, END)
e.insert(0, f_num + int(fourth_number))
def button_exponents():
fifth_number = e.get()
e.delete(0, END)
e.insert(0, f_num + int(fifth_number))
def button_equal():
sixth_number = e.get()
e.delete(0, END)
e.insert(0, f_num + int(sixth_number))
button_1 = Button(root_var, text="1", padx=50, pady=10, command=lambda: button_click(1))
button_2 = Button(root_var, text="2", padx=50, pady=10, command=lambda: button_click(2))
button_3 = Button(root_var, text="3", padx=50, pady=10, command=lambda: button_click(3))
button_4 = Button(root_var, text="4", padx=50, pady=10, command=lambda: button_click(4))
button_5 = Button(root_var, text="5", padx=50, pady=10, command=lambda: button_click(5))
button_6 = Button(root_var, text="6", padx=50, pady=10, command=lambda: button_click(6))
button_7 = Button(root_var, text="7", padx=50, pady=10, command=lambda: button_click(7))
button_8 = Button(root_var, text="8", padx=50, pady=10, command=lambda: button_click(8))
button_9 = Button(root_var, text="9", padx=50, pady=10, command=lambda: button_click(9))
button_0 = Button(root_var, text="0", padx=50, pady=10, command=lambda: button_click(0))
button_addition = Button(root_var, text="+", padx=50, pady=10, command=button_add)
button_subtraction = Button(root_var, text="-", padx=50, pady=10, command=button_subtract)
button_multiplication = Button(root_var, text="*", padx=50, pady=10, command=button_multiply)
button_division = Button(root_var, text="/", padx=50, pady=10, command=button_divide)
button_exponents = Button(root_var, text="^", padx=50, pady=10, command=button_exponents)
button_equals = Button(root_var, text="=", padx=50, pady=10, command=button_equal)
button_clear = Button(root_var, text="C", padx=50, pady=10, command=button_clear)
button_1.grid(row=3, column=2)
button_2.grid(row=3, column=1)
button_3.grid(row=3, column=0)
button_4.grid(row=2, column=2)
button_5.grid(row=2, column=1)
button_6.grid(row=2, column=0)
button_7.grid(row=1, column=2)
button_8.grid(row=1, column=1)
button_9.grid(row=1, column=0)
button_0.grid(row=4, column=0)
button_addition.grid(row=4, column=1)
button_subtraction.grid(row=4, column=2)
button_multiplication.grid(row=5, column=0)
button_division.grid(row=5, column=1)
button_exponents.grid(row=5, column=2)
button_equals.grid(row=6, column=0)
button_clear.grid(row=6, column=1)
root_var.mainloop()
The addition operation works. I want the other operations to also be able to perform their respective tasks.
When one of the operators is clicked, you need to save the current input number to f_num and the operator to another variable, for example opr.
Then when = is clicked, do the calculation based on the saved opr, f_num and current input value.
Below is an example based on your code:
from tkinter import *
root_var = Tk()
root_var.title("Calculator")
e = Entry(root_var, width=25, borderwidth=5)
e.grid(row=0, column=0, columnspan=3, padx=10, pady=10)
f_num = opr = None
def button_click(number=None):
current = e.get()
e.delete(0, END)
e.insert(0, current+str(number))
def button_opr(op):
global f_num, opr
# save the first number and operator
try:
f_num = int(e.get())
opr = op
# clear the entry
e.delete(0, END)
except Exception as ex:
print(ex)
def button_clear():
global f_num, opr
e.delete(0, END)
# reset first number and operator
f_num = opr = None
def button_equal():
global f_num, opr
if f_num and opr:
try:
current = int(e.get())
e.delete(0, END)
if opr == "+":
e.insert(0, f_num+current)
elif opr == "-":
e.insert(0, f_num-current)
elif opr == "*":
e.insert(0, f_num*current)
elif opr == "/":
e.insert(0, f_num/current)
elif opr == "^":
e.insert(0, f_num**current)
except Exception as ex:
print(ex)
# reset first number and operator
f_num = opr = None
button_1 = Button(root_var, text="1", padx=50, pady=10, command=lambda: button_click(1))
button_2 = Button(root_var, text="2", padx=50, pady=10, command=lambda: button_click(2))
button_3 = Button(root_var, text="3", padx=50, pady=10, command=lambda: button_click(3))
button_4 = Button(root_var, text="4", padx=50, pady=10, command=lambda: button_click(4))
button_5 = Button(root_var, text="5", padx=50, pady=10, command=lambda: button_click(5))
button_6 = Button(root_var, text="6", padx=50, pady=10, command=lambda: button_click(6))
button_7 = Button(root_var, text="7", padx=50, pady=10, command=lambda: button_click(7))
button_8 = Button(root_var, text="8", padx=50, pady=10, command=lambda: button_click(8))
button_9 = Button(root_var, text="9", padx=50, pady=10, command=lambda: button_click(9))
button_0 = Button(root_var, text="0", padx=50, pady=10, command=lambda: button_click(0))
button_addition = Button(root_var, text="+", padx=50, pady=10, command=lambda: button_opr("+"))
button_subtraction = Button(root_var, text="-", padx=50, pady=10, command=lambda: button_opr("-"))
button_multiplication = Button(root_var, text="*", padx=50, pady=10, command=lambda: button_opr("*"))
button_division = Button(root_var, text="/", padx=50, pady=10, command=lambda: button_opr("/"))
button_exponents = Button(root_var, text="^", padx=50, pady=10, command=lambda: button_opr("^"))
button_equals = Button(root_var, text="=", padx=50, pady=10, command=button_equal)
button_clear = Button(root_var, text="C", padx=50, pady=10, command=button_clear)
button_1.grid(row=3, column=2, sticky="ew")
button_2.grid(row=3, column=1, sticky="ew")
button_3.grid(row=3, column=0, sticky="ew")
button_4.grid(row=2, column=2, sticky="ew")
button_5.grid(row=2, column=1, sticky="ew")
button_6.grid(row=2, column=0, sticky="ew")
button_7.grid(row=1, column=2, sticky="ew")
button_8.grid(row=1, column=1, sticky="ew")
button_9.grid(row=1, column=0, sticky="ew")
button_0.grid(row=4, column=0, sticky="ew")
button_addition.grid(row=4, column=1, sticky="ew")
button_subtraction.grid(row=4, column=2, sticky="ew")
button_multiplication.grid(row=5, column=0, sticky="ew")
button_division.grid(row=5, column=1, sticky="ew")
button_exponents.grid(row=5, column=2, sticky="ew")
button_equals.grid(row=6, column=0, sticky="ew")
button_clear.grid(row=6, column=1, sticky="ew")
root_var.mainloop()