How can I parse a string number to a float python

Question

from excel I have a number in the following type: "22.024.833,02 ", so I've been trying .strip(), .replace() among others but I couldn't get a float from my code.

for columna, fila in mav.iterrows():
    comitente = fila['Comit.']
    moneda = fila['Especie']
    m = fila['Operado'].strip()
    m2 = m.replace('.', '')
    monto = float(m2)

Result: monto = float(m2) ValueError: could not convert string to float: '22024833,02'

Does this answer your question? [How can I convert a string with dot and comma into a float in Python](https://stackoverflow.com/questions/6633523/how-can-i-convert-a-string-with-dot-and-comma-into-a-float-in-python) — Renat, Dec 23 '21 at 20:19
@Renat, it looks like OP is using the dot for separating digits and the comma for the decimal point, so that answer doesn't quite get there. — CoffeeTableEspresso, Dec 23 '21 at 20:20
@CoffeeTableEspresso, it's still a number in a localized format, which is addressed in that question — Renat, Dec 23 '21 at 20:26
@Renat you're correct, I did not see the answer that dealt with this initially when looking at that question — CoffeeTableEspresso, Dec 23 '21 at 20:28
Answered here https://stackoverflow.com/a/56114791/11687201 just set additional parameters for the file reading with pandas. — ai2ys, Dec 23 '21 at 20:31
Does this answer your question? [How to convert a string to a number if it has commas in it as thousands separators?](https://stackoverflow.com/questions/1779288/how-to-convert-a-string-to-a-number-if-it-has-commas-in-it-as-thousands-separato) — mkrieger1, Dec 23 '21 at 20:36

CoffeeTableEspresso · Answer 1 · 2021-12-23T20:24:39.923

2

My answer is assuming you're using . for digit separator and , for the decimal point.

m = fila['Operado'].strip()    # m = "22.024.833,02"
m = m.replace('.', '')         # m = "22024833,02"
m = m.replace(',', '.')        # m = "22024833.02"
monto = float(m)               # monto = 22024833.02

Python's float expects no digit separator (the . in your example), and the decimal point to be a . (not a , as in your input).

edited Dec 23 '21 at 20:24

answered Dec 23 '21 at 20:19

CoffeeTableEspresso

2,614
1
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The answer is about string->float conversion, not about getting a single string from a csv file's row. Btw I found really usefull to read the comments next to your code to better understand what the OP was really asking. +1 – FLAK-ZOSO Dec 23 '21 at 21:00
@FLAK-ZOSO You're right, reading from the file is not important at all, I just formatted it this way to align with what was in OPs post. – CoffeeTableEspresso Dec 24 '21 at 06:03

score 1 · Answer 2 · answered Dec 23 '21 at 20:27

1

I think this is what you are looking for

m = float(fila['Operado'].strip().replace(".","").replace(",","."))

Its better to use . for decimal places and , for the whole number part.

answered Dec 23 '21 at 20:27

Rachit Kawar

74
5

I had also tried replacing "," for "." but it didnt work guys, i tried it again and it worked! I appreciatate your comments , thank you guys!!! – leandro stimoli Dec 23 '21 at 21:04

FLAK-ZOSO · Answer 3 · 2021-12-23T20:30:31.257

In Python you should use . instead of , as decimal separator.

good_float = 1.44
not_a_float = 1,22 # This will be stored as a tuple

If your input string is written with , as decimal separator, you can use String.replace() method.

>>> '3,14'.replace(',', '.')
'3.14'

If you are also using . as digit separator, you can replace it with the same method.

>>> '1.203,14'.replace('.', ' ').replace(',', '.')
'1203,14'

Then you can finely convert the string to a float using the float built-in function.

>>> float('3,14'.replace('.', ' ').replace(',', '.'))
3.14

Remember to always write .replace('.', ' ') before .replace(',', '.') to avoid a mess with periods.

Your code should work now:

>>> float(fila['Operado'].strip().replace('.', ' ').replace(',', '.'))

How can I parse a string number to a float python

3 Answers3