I have a weird issue of python when i am trying to use pycharm

Question

I wrote a length converter with python, here are the codes:

active = True
while active:
    option = input('please choose：\na:centimetre to inch \nb:inch to centimetre：')
    if option == "a":
        centimetre = input('Please enter centimetre:')
        centimetre= float (centimetre)
        inch = centimetre / 2.54
        print(str(centimetre) + ' centimetre equals' + str(inch) + ' inches')

    elif option == "b": 
        inch = input('Please enter inch:')
        inch = float ( inch )
        centimetre = inch * 2.54
        print(str(inch) + ' inch equals ' + str(centimetre) + ' centimetre')

    else:
        print("sorry you entered wrong option。please enter 'a'or'b': ")
        continue  

    status = input('continue？ yes/no ：')
    if status == 'no':
        active = False

It's ok when these codes run with notepad++ and http://www.pythontutor.com/

but when I try to use pycharm, it got error:

line 6, in <module>
centimetre= float (centimetre)
ValueError: could not convert string to float:

not sure where is the problems. Has anyone met this issue?

I am guessing they are configured to use different python versions. Which ones are you using? — FlyingTeller, Jul 27 '18 at 08:42
`pi_float = float(pi_string)` [LINK](https://stackoverflow.com/questions/38350482/how-to-convert-string-into-float) — R. García, Jul 27 '18 at 08:45
@R.García Not very helpful as the code itself as posted is correct — FlyingTeller, Jul 27 '18 at 08:55

score 1 · Answer 1 · answered Mar 16 '21 at 21:33

You could try checking if the input is able to be converted into a float, using try:.
And, also, if it's an issue with Python not recognizing commas as a decimal point, and maybe periods as a thousands separator, then you could check for if the number with commas and periods swapped (using the .replace() method).

An example of this is:

x = '2.3'
y = '3,4'


def isnumber(num):
    try:
        float(num)
        return True
    except ValueError:
        try:
            float(num.replace(',', 'A').replace('.', 'B').replace('A', '.').replace('B', ','))
            return True
        except ValueError:
            return False


if isnumber(x):
    print(f'The number {x} is valid.')
else:
    print(f'The number {x} is not valid.')

print()

if isnumber(y):
    print(f'The number {y} is valid.')
else:
    print(f'The number {y} is not valid.')

Peter Majko · Answer 2 · 2018-07-27T09:02:12.793

0

You are probably using wrong decimal separator on input. Perhaps comma "," instead of full stop "."

You need to replace that or catch the error (or both together). I suggest:

try:
    centimetre = float(centimetre.replace(',', '.'))
except ValueError:
    print('Input is not a valid number or in invalid format!')

edited Jul 27 '18 at 09:02

answered Jul 27 '18 at 08:52

Peter Majko

1,241
11
22

I tried it out by myself: >>> a = input() >>> a '1,3' >>> float(a) Traceback (most recent call last): File "", line 1, in ValueError: could not convert string to float: '1,3' – Peter Majko Jul 27 '18 at 08:56

score 0 · Answer 3 · answered Aug 01 '18 at 00:57

0

i tried days to fix it and have solved this issue
i created a brand new project in pycharm and put the code in a new file.
it works now
if you just copy and paste the code to existed pycharm project, it might not work
not sure why, but at least it's not my codes' fault and it works now.

answered Aug 01 '18 at 00:57

james shaw

7
2

One word (probably): encoding :-) – Peter Majko Oct 27 '18 at 14:17

score -1 · Answer 4 · answered Jul 27 '18 at 08:44

-1

Try this:

centimetre = float(input('Please enter centimetre:'))

answered Jul 27 '18 at 08:44

Hayat

1,539
4
18
32

1

Question Repeated: https://stackoverflow.com/questions/38350482/how-to-convert-string-into-float – R. García Jul 27 '18 at 08:45
There is no difference if you first save it into a variable and then convert or convert directly – FlyingTeller Jul 27 '18 at 08:54
@FlyingTeller the code is was working fine at my end. – Hayat Jul 27 '18 at 09:43

I have a weird issue of python when i am trying to use pycharm

4 Answers4