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how to make a calculator in python
gatorade322 (92)

This is going to be a tutorial for beginners who know the basics of python. That is floats, and input and print. So, were going to start with two lines of code:

import math
while True:
    math = input()

This will get the computer the information for it to know if we are going to do multiplication, division, addition, or subtraction. We will start with addition:

    if d == “plus”:
        digit_1 = input()
        digit_2 = input()

This will get us all the inputs we need. If you want, you can add a + or plus in there, but I just just put nothing. This is what it would look like if there was a plus:

    if d == “plus”:
         digit_1 = input()
         digit_2 = input(“plus or +”)

Next we need to add it together. We can’t do answer = digit_1 + digit_2, or that would be monkey math (which would be funny, but we don’t want it in our calculator). You can do that if you want. So we will just add float(digit_1) + float(digit_2) instead:

answer = float(digit_1) + float(digit_2)
print(answer)

The rest of the code is basically the same, but with -, *, and /. So just copy and paste this all in to your repl:

    elif d == "minus":
        a = input()
        b = input()
        c = float(a) - float(b)
        print(c)

    elif d == "square":
        a = input()
        b = float(a) * float(a)
        print(b)

    elif d == "divide":
        a = input()
        b = input()
        if b == "0":
            print("infinity")
        else:
             c = float(a) / float(b)
             print(c)
    
    elif d == "times":
        a = input()
        b = input()
        c = float(a) * float(b)
        print(c)

It’s pretty simple. I’ll just explain the infinity filter. If you divide anything by zero it’s infinity. If you don’t add the filter, there will be a divide by zero error. So we just check if it’s zero, and if it is, it will print infinity. Also simple!

I hope you liked this tutorial. It was really fun to make. I also hope this influences future coding, and I hope you have fun coding!
Goodbye.

Comments
hotnewtop
XanderEhlert (144)

you can do this in one line:

print('Your calculation comes to {0}.'.format(eval(input('What do you want to calculate?'))))
gatorade322 (92)

I'll try that. I might not be able to post the new version though. Upvote for the seggustion! :D

XanderEhlert (144)

@gatorade322 good tutorial, ill give you an upvote

one more thing: you never say what d is

gatorade322 (92)

you're right. That's an error. At the top, just assume math is d. Thanks for the upvote though!

ANoobpro (1)

it says line 4 invalid syntax

Codemonkey51 (923)

Cool! This is a great tutorial for anyone who wants to make a calculator

gatorade322 (92)

I just posted part one of 2D minecraft. You should check it out. It should be one of the first things in the learn section

Denalgus2 (0)

guys, can someone help? It says that line 4 is invalid. I have tried everthing but It doesnt help

neimat (0)

For some reason my calculator is only adding? I'm not sure where the error is.

https://repl.it/join/ncnmyjmg-neimat

gatorade322 (92)

@neimat I don't know, did you use all the code?

patricksutherla (0)

no me sirve me manda codigo de error