Drop all data in a pandas dataframe
PythonPython 2.7PandasPython Problem Overview
I would like to drop all data in a pandas dataframe, but am getting TypeError: drop() takes at least 2 arguments (3 given). I essentially want a blank dataframe with just my columns headers.
import pandas as pd
web_stats = {'Day': [1, 2, 3, 4, 2, 6],
'Visitors': [43, 43, 34, 23, 43, 23],
'Bounce_Rate': [3, 2, 4, 3, 5, 5]}
df = pd.DataFrame(web_stats)
df.drop(axis=0, inplace=True)
print df
Python Solutions
Solution 1 - Python
You need to pass the labels to be dropped.
df.drop(df.index, inplace=True)
By default, it operates on axis=0.
You can achieve the same with
df.iloc[0:0]
which is much more efficient.
Solution 2 - Python
My favorite:
df = df.iloc[0:0]
But be aware df.index.max() will be nan. To add items I use:
df.loc[0 if math.isnan(df.index.max()) else df.index.max() + 1] = data
Solution 3 - Python
My favorite way is:
df = df[0:0]
Solution 4 - Python
Overwrite the dataframe with something like that
import pandas as pd
df = pd.DataFrame(None)
or if you want to keep columns in place
df = pd.DataFrame(columns=df.columns)
Solution 5 - Python
If your goal is to drop the dataframe, then you need to pass all columns. For me: the best way is to pass a list comprehension to the columns kwarg. This will then work regardless of the different columns in a df.
import pandas as pd
web_stats = {'Day': [1, 2, 3, 4, 2, 6],
'Visitors': [43, 43, 34, 23, 43, 23],
'Bounce_Rate': [3, 2, 4, 3, 5, 5]}
df = pd.DataFrame(web_stats)
df.drop(columns=[i for i in check_df.columns])
Solution 6 - Python
This code make clean dataframe:
df = pd.DataFrame({'a':[1,2], 'b':[3,4]})
#clean
df = pd.DataFrame()