How to convert a ' ' to an int?-CodePudding

I have a dataframe with a column that is objects. When i check for null values the data set says it has no null values but there is one row thats has a ' ' for age. I want to convert the column from object to int but that 1 value is giving me a hard time.

Here is what i have tried:

df['perpetrator_age'].replace('', '0', regex=True)
df.head()

Which does not replace the value.

df['perpetrator_age'].astype(int)

ValueError: invalid literal for int() with base 10: ' '

After some searching i thought maybe try convert it to a float first but :

df['perpetrator_age'].astype(float).astype(int)

ValueError: could not convert string to float: ''

Any help appreciated!

CodePudding user response：

As I mentioned in my comment, I guess the assingment is missing.

Here is a very basic example with an '' string.

import pandas as pd

df = pd.DataFrame({'a':[1,2,3,'',4,5]})
df['a'].replace('',0, inplace=True)
# df['a'] = df['a'].replace('',0) as an equivilant
>>> df.head()
   a
0  1
1  2
2  3
3  0
4  4
5  5

CodePudding user response：

try: df['perpetrator_age'].astype('int')

Don't forget the ' '

CodePudding user response：

Based on this error message ValueError: invalid literal for int() with base 10: ' ' the issue that you have is that there is a field with one space, not an empty string. This is why the replace is failing. If you run df['perpetrator_age'].replace(' ', '0', regex=True) this will work.

CodePudding user response：

Well friends, it turns out a simple inplace=True solved all of my problems!

df['perpetrator_age'].replace(' ', 0, regex=False, inplace=True)

df['perpetrator_age'].astype(int)

Thank you everyone for your help :)