Inputing boolean values with python

Question

I am building a simple program to pre-screen tenants for my rental properties. The program asks them a series of questions - some of which require a "yes" or "no" answer which would be a boolean (true/false).

The problem is, no matter what you answer for the boolean inputs it records as "1".

I'm using sqlite3 locally to store the data, here's the code:

def enter_dynamic_data():
     fname = input("First Name? ")
     lname = input("Last Name? ")
     email = input("Email? ")
     phone = input("Phone? ")
     criminal = bool(input("Have you ever been convicted of a crime? "))
     evicted = bool(input("Have you ever been evicted? "))
     income = bool(input("Do you have verifiable income of at least 3x the rent amount? "))
     ref = bool(input("Do you have good rental references? "))

     c.execute("INSERT INTO tenant_screening (firstname, lastname, email, phone, criminal, evicted, income, ref) VALUES (?, ?, ?, ?, ?, ?, ?, ?)", (fname, lname, email, phone, criminal, evicted, income, ref))

It's because bool() function evaluates everything to True (1) except things like empty lists/tuples, None, False, or empty strings. Saying bool("anything") is always evaluated to True, because there is something. — Nf4r, Oct 02 '16 at 23:56
Pretty much what the duplicate is stating is that sqllite3 bools are stored as 0, 1. *SQLite does not have a separate Boolean storage class*. [doc](http://www.sqlite.org/datatype3.html) for reference — idjaw, Oct 02 '16 at 23:58
As easy as: answer = input().lower() == "yes";. You can also do other checking as: answer = int(input()) > 100; etc.. — dinomoth, Jul 05 '17 at 22:06

score 1 · Answer 1 · answered Oct 03 '16 at 00:01

In Python any non-empty string is considered True so regardless of the user's input all non-empty strings entered by the user will be True when converted to boolean.

>>> bool('true')
True
>>> bool('false')
True
>>> bool('')
False

So you need to compare the value entered by the user against a set of values that represent True, e.g.

YES_VALUES = {'y', 'yes', 'ok'}

criminal = input("Have you ever been convicted of a crime? ").lower() in YES_VALUES

This converts the user's input to lower case and then checks whether that value is in the set YES_VALUES. The result of x in y is already a boolean, so explicit conversion via bool is not required.

score 0 · Accepted Answer · answered Oct 03 '16 at 00:08

0

Wrapping the input in Boolean will always return True if the input is not None. Instead you could do something like:

response = False if raw_input("The yesno question? ").lower() == 'no' else True

answered Oct 03 '16 at 00:08

Matz

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Inputing boolean values with python

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