Just a quick Question

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September 23rd, 2012, 05:11 PM

Nick Wyden

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Just a quick Question

So I am trying to do a conditional statement using boolean logic my code is

Rock = True

Goth = False

Pop = True

music = input ("what is your fav music ")

if music == True:

print ("That is Good Music")

else:
print (" No that sucks")

However when I run this script every time I input Rock , or I input Pop the programs prints the function assigned to else

what am I doing wrong?

September 23rd, 2012, 05:54 PM

b49P23TIvg

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The answer depends upon whether you're using python 3 or an earlier version.

In python 3 input returns a string which is never equal to the Boolean data type value True and so the else event always happens.

In python 2 input evaluates the string you type, and returns that. Thus, in python2 the entries of
True
or
1
would cause the true branch of the if statement to execute.

(or if you happen to have a variable named a with the value of 1 assigned to it you could enter a as well.)

[edit] false sentence removed [/edit]

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Last edited by b49P23TIvg : September 24th, 2012 at 04:10 PM.

September 23rd, 2012, 08:27 PM

Nick Wyden

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Quote:

Originally Posted by b49P23TIvg

alright thanks

two quick things 1) I got a book called python 3 for absolute beginners is this good for learning and 2) so I would have to convert the string into a numerical data string right

Comments on this post

b49P23TIvg agrees: I apologize for earlier negative remarks.

September 23rd, 2012, 08:38 PM

b49P23TIvg

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Yes, exactly.

Oh, you are using python3. Reading this with a python3 point of view I've inserted the error trapped eval statement

Code:

Rock = True
Goth = False 
Pop = True
string = input ("what is your fav music ")

try:
    music = eval(string)
except:
    music = False

if music == True:
    print ("That is Good Music") 
else: 
    print (" No that sucks")