Python Flask division error

Question

I need help with my Python Flask application. I'm trying to give a user the result of a division that they specify, but it's not working. When the user submits "5" and "2" for example, it returns "2" instead of "2.5". I have no idea why it would do this.

Below is my code... can anybody figure out why this would happen?

from flask import Flask, session, render_template, request
app = Flask(__name__)
app.secret_key = 'wlFw0WP7SrNmAMF1wJaUSjWMTYdTay8EDIA3FPQhbo9c7wQ9rIdQrzJRzcN1o3mp'

@app.route('/',methods=['GET','POST'])
def index():
    [...]
    if request.method == 'POST':
        a = int(request.form['a'])
        b = int(request.form['b'])
        result = a/b
        return render_template('index.html',session=session,result=result)
    return render_template('index.html',session=session)

# Other routes omitted

if __name__ == '__main__':
    app.run(host='0.0.0.0')

possible duplicate of [Python division](http://stackoverflow.com/questions/2958684/python-division) — gengkev, Apr 26 '15 at 02:44

score 4 · Accepted Answer · answered Nov 20 '14 at 02:45

4

In Python 2, dividing an int by another int will perform integer division.

To get around this, you can multiply a by 1.0, converting it to a float, before dividing by b:

result = a*1.0/b

This should give you the expected 2.5 instead of 2.

answered Nov 20 '14 at 02:45

sdamashek

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Or you can initialize a,b=.0,.0 without multiplying by 1.0, in other ords, u should make it as a float – user3001937 Nov 20 '14 at 02:48

score 0 · Answer 2 · answered Nov 20 '14 at 02:47

0

add this line at the beginning of ur source code.

from __future__ import division

answered Nov 20 '14 at 02:47

user3001937

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http://stackoverflow.com/questions/7075082/what-is-future-in-python-used-for-and-how-when-to-use-it-and-how-it-works – user3001937 Nov 20 '14 at 09:19

score -1 · Answer 3 · edited Oct 23 '17 at 21:13

-1

Depending on the version of Python you are using, the results may be different. See this question for more details. But in a nutshell, it looks like, in order for you to see a float result, you will need convert the numbers into floats first as the below

a = float(request.form["a"])
a = float(request.form["b"])

edited Oct 23 '17 at 21:13

Suhas

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answered Oct 23 '17 at 18:19

Jjagwe Dennis

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Python Flask division error

3 Answers3