How to filter a DataFrame
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Here is how you can apply a filter on a pandas DataFrame.
We define a sample DataFrame
You can download it here if the above script doesn't work for you and read it like so
One conditional statement mask
A condition within squared brackets
it is also possible to it in one-line
N conditional statements
It is possible to add more than one conditional statement like so
Or the oneliner :
What can you filter for?
Where text equals
Where text contains
There is a similar method for filtering where the text contains a string.
That might be useful when you are trying to filter out a specific email out of an email list and knows the prefix before the @ sign.
Filter for specific dates
Here is how to filter for dates that start on a specific date and end on another specific date.
# we import the library
import pandas as pd
dates = pd.date_range(start="2021-01-01", end="2022-01-02", freq="D")
# we create the sample dataframe with dates
df = pd.DataFrame({"date": dates,
"col1":range(len(dates))})
# We filter for rows that starts on the 2021-06-01 and ends on the 2021-07-01
df[(df["date"] >= "2021-06-01") & (df["date"] <= "2021-07-01")]
Boolean filter
# we import the Pandas library
import pandas as pd
dates = pd.date_range(start="2021-01-01", end="2022-01-02", freq="D")
# we create the sample dataframe with dates
df = pd.DataFrame({"date": dates,
"col1":range(len(dates))})
# We filter for rows that starts on the 2021-06-01 and ends on the 2021-07-01
df[(df["date"] >= "2021-06-01") & (df["date"] <= "2021-07-01")]
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A proven roadmap to prepare for $75K+ entry-level data roles. Perfect for Data Scientist ready to level up their career.
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