Convert List In String Format Back To List Of Float Numbers

str = [ 3.82133931e-01 4.27354313e-02 1.94678816e-03 0.00000000e+00 0.00000000e+00 0.00000000e+00 0.00000000e+00 0.00000000e+00 0.00000000e+00 0.00000000e+00

Solution 1:

It seems like you should be able to just strip off the [ and ]:

str = str.replace('[', '').replace(']', '')

And then split the string calling float on each member of the split string:

floats = [float(x) for x in str.split()]

Notice that because python strings are immutable, things like:

str.replace('[', '')

Doesn't change str in place. Instead, it returns a new string with the requested characters removed. Since it returns a new string, we need to give that string a name (I just chose to give it the name str again to avoid using too many names...)

Solution 2:

How about this:

floats = [ float(x) for x in re.findall('\d+\.\d+e[+\-]\d\d', str)]

Solution 3:

You should be storing your numbers in your database as floats rather than strings.

If you're using postgres you can make use of the ArrayField

from django.contrib.postgres.fields import ArrayField
my_floats = ArrayField(models.FloatField())

If you're not, you should still store them as numbers but it may require a different relational model.