Drop Rows Containing Empty Cells from a Pandas Dataframe

Drop rows containing empty cells from a pandas DataFrame

Pandas will recognise a value as null if it is a np.nan object, which will print as NaN in the DataFrame. Your missing values are probably empty strings, which Pandas doesn't recognise as null. To fix this, you can convert the empty stings (or whatever is in your empty cells) to np.nan objects using replace(), and then call dropna()on your DataFrame to delete rows with null tenants.

To demonstrate, we create a DataFrame with some random values and some empty strings in a Tenants column:

>>> import pandas as pd
>>> import numpy as np
>>>
>>> df = pd.DataFrame(np.random.randn(10, 2), columns=list('AB'))
>>> df['Tenant'] = np.random.choice(['Babar', 'Rataxes', ''], 10)
>>> print df

A B Tenant
0 -0.588412 -1.179306 Babar
1 -0.008562 0.725239
2 0.282146 0.421721 Rataxes
3 0.627611 -0.661126 Babar
4 0.805304 -0.834214
5 -0.514568 1.890647 Babar
6 -1.188436 0.294792 Rataxes
7 1.471766 -0.267807 Babar
8 -1.730745 1.358165 Rataxes
9 0.066946 0.375640

Now we replace any empty strings in the Tenants column with np.nan objects, like so:

>>> df['Tenant'].replace('', np.nan, inplace=True)
>>> print df

A B Tenant
0 -0.588412 -1.179306 Babar
1 -0.008562 0.725239 NaN
2 0.282146 0.421721 Rataxes
3 0.627611 -0.661126 Babar
4 0.805304 -0.834214 NaN
5 -0.514568 1.890647 Babar
6 -1.188436 0.294792 Rataxes
7 1.471766 -0.267807 Babar
8 -1.730745 1.358165 Rataxes
9 0.066946 0.375640 NaN

Now we can drop the null values:

>>> df.dropna(subset=['Tenant'], inplace=True)
>>> print df

A B Tenant
0 -0.588412 -1.179306 Babar
2 0.282146 0.421721 Rataxes
3 0.627611 -0.661126 Babar
5 -0.514568 1.890647 Babar
6 -1.188436 0.294792 Rataxes
7 1.471766 -0.267807 Babar
8 -1.730745 1.358165 Rataxes

Delete rows from pandas dataframe if all its columns have empty string

You can do:

# df.eq('') compare every cell of `df` to `''`
# .all(1) or .all(axis=1) checks if all cells on rows are True
# ~ is negate operator.
mask = ~df.eq('').all(1)

# equivalently, `ne` for `not equal`,
# mask = df.ne('').any(axis=1)

# mask is a boolean series of same length with `df`
# this is called boolean indexing, similar to numpy's
# which chooses only rows corresponding to `True`
df = df[mask]

Or in one line:

df = df[~df.eq('').all(1)]

Only remove entirely empty rows in pandas

Check the docs page

df.dropna(how='all')


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