To convert a column that includes a mixture of float and NaN values to int, first replace NaN values with zero on pandas DataFrame and then use astype() to convert. Use DataFrame. fillna() to replace the NaN values with integer value zero. Yields below output.
Since a float is bigger than int, you can convert a float to an int by simply down-casting it e.g. (int) 4.0f will give you integer 4. By the way, you must remember that typecasting just get rid of anything after the decimal point, they don't perform any rounding or flooring operation on the value.
Python also has a built-in function to convert floats to integers: int() . In this case, 390.8 will be converted to 390 . When converting floats to integers with the int() function, Python cuts off the decimal and remaining numbers of a float to create an integer.
parameter dtype allows a pass a dictionary of column names and target types like dtype = {"my_column": "Int64"} parameter converters can be used to pass a function that makes the conversion, for example changing NaN's with 0. converters = {"my_column": lambda x: int(x) if x else 0}
To modify the float output do this:
df= pd.DataFrame(range(5), columns=['a'])
df.a = df.a.astype(float)
df
Out[33]:
a
0 0.0000000
1 1.0000000
2 2.0000000
3 3.0000000
4 4.0000000
pd.options.display.float_format = '{:,.0f}'.format
df
Out[35]:
a
0 0
1 1
2 2
3 3
4 4
Use the pandas.DataFrame.astype(<type>)
function to manipulate column dtypes.
>>> df = pd.DataFrame(np.random.rand(3,4), columns=list("ABCD"))
>>> df
A B C D
0 0.542447 0.949988 0.669239 0.879887
1 0.068542 0.757775 0.891903 0.384542
2 0.021274 0.587504 0.180426 0.574300
>>> df[list("ABCD")] = df[list("ABCD")].astype(int)
>>> df
A B C D
0 0 0 0 0
1 0 0 0 0
2 0 0 0 0
EDIT:
To handle missing values:
>>> df
A B C D
0 0.475103 0.355453 0.66 0.869336
1 0.260395 0.200287 NaN 0.617024
2 0.517692 0.735613 0.18 0.657106
>>> df[list("ABCD")] = df[list("ABCD")].fillna(0.0).astype(int)
>>> df
A B C D
0 0 0 0 0
1 0 0 0 0
2 0 0 0 0
Considering the following data frame:
>>> df = pd.DataFrame(10*np.random.rand(3, 4), columns=list("ABCD"))
>>> print(df)
... A B C D
... 0 8.362940 0.354027 1.916283 6.226750
... 1 1.988232 9.003545 9.277504 8.522808
... 2 1.141432 4.935593 2.700118 7.739108
Using a list of column names, change the type for multiple columns with applymap()
:
>>> cols = ['A', 'B']
>>> df[cols] = df[cols].applymap(np.int64)
>>> print(df)
... A B C D
... 0 8 0 1.916283 6.226750
... 1 1 9 9.277504 8.522808
... 2 1 4 2.700118 7.739108
Or for a single column with apply()
:
>>> df['C'] = df['C'].apply(np.int64)
>>> print(df)
... A B C D
... 0 8 0 1 6.226750
... 1 1 9 9 8.522808
... 2 1 4 2 7.739108
This is a quick solution in case you want to convert more columns of your pandas.DataFrame
from float to integer considering also the case that you can have NaN values.
cols = ['col_1', 'col_2', 'col_3', 'col_4']
for col in cols:
df[col] = df[col].apply(lambda x: int(x) if x == x else "")
I tried with else x)
and else None)
, but the result is still having the float number, so I used else ""
.
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With