Converting a list of strings to a list of floats

Question

Given a list of strings

['2.13', '4.67', '-6.1']

is there a way to convert this list into a list of floats?

convert it when you read it from the file using the `float` function — Paul H, Apr 05 '21 at 15:24
Also you can iterate directly on the `filehandle` to go over the file line-by-line. You should be sure to check for if the line is empty as well, because may programs will end the file with a blank line. — Aaron, Apr 05 '21 at 15:29

score 1 · Answer 1 · answered Apr 05 '21 at 15:29

You can convert strings into floats using float(string_value).

>>> value = '3.14159'
>>> float(value)
3.14159

Edit: some more info:

Note that if string_value is not a valid float, Python will raise a ValueError:

>>> value = 'not a float'
>>> float(value)
ValueError: could not convert string to float: 'not a float'

So if there's a chance your file has invalid values in it, it may be worth doing:

try:
    float_value = float(value)
except ValueError:
    # Handle errors here

Asker · Answer 2 · 2021-04-05T17:37:24.223

-1

my_float_list = list(map(float, ['2.13', '4.67', '-6.1']))

Relevant docs:

edited Apr 05 '21 at 17:37

answered Apr 05 '21 at 16:04

Asker

score -2 · Answer 3 · edited Apr 05 '21 at 18:41

-2

Try this simple loop:

my_string_list = ['2.13', '4.67', '-6.1']
my_float_list = []
for item in my_string_list:
    my_float_list.append(float(item))

edited Apr 05 '21 at 18:41

Frightera

answered Apr 05 '21 at 16:38

daniele crespini

3 Answers3