What have I done wrong? - Printable Version

What have I done wrong? - Printable Version

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What have I done wrong? - Gandalf - Sep-23-2019

So I am new to learning Phyton and I don't know what I did wrong here, I would appreciate it if you could help me and also if you could simplify your explanation a bit.

This is the code:

birthyear = input(' in what year were you born? ')
age = 2019 - int(birthyear)
print(' you are ' + age + ' years old. ')

And this is the error I get:

Error:Traceback (most recent call last):
  File "C:/Users/alicf/PycharmProjects/NOOB/yildan yas hesabi/erdo.py", line 3, in <module>
    print(' you are ' + age + ' years old. ')
TypeError: can only concatenate str (not "int") to str

RE: What have I done wrong? - micseydel - Sep-23-2019

The problem is that the + operator can't be used between a string (' you are ') and an int, such as age. So you need to either convert the int to a string before using the plus operator, like this:

print(' you are ' + str(age) + ' years old. ')

or better yet, use string formatting

print(' you are {} years old. '.format(age))

or if you're using the latest version of Python, you can even do this

print(f' you are {age} years old. ')

RE: What have I done wrong? - Gandalf - Sep-23-2019

Thanks for your help, and what does the f stand for on your last example?

RE: What have I done wrong? - perfringo - Sep-23-2019

(Sep-23-2019, 02:07 AM)Gandalf Wrote: Thanks for your help, and what does the f stand for on your last example?

f stands for 'formatted (string literal)'. It's available from Python 3.6 and you can read about in PEP 498 -- Literal String Interpolation

RE: What have I done wrong? - Gandalf - Sep-23-2019

Got it thanks again for your help.