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How to Check Column Nulls and Replace: Pandas

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Here is a post that shows how to count Nulls and replace them with the value you want in the Pandas Dataframe. We have explained the process in two steps - Counting and Replacing the Null values. Count null values (column-wise) in Pandas ## count null values column-wise null_counts = df.isnull(). sum() print(null_counts) ``` Output: ``` Column1    1 Column2    1 Column3    5 dtype: int64 ``` In the above code, we first create a sample Pandas DataFrame `df` with some null values. Then, we use the `isnull()` function to create a DataFrame of the same shape as `df`, where each element is a boolean value indicating whether that element is null or not. Finally, we use the `sum()` function to count the number of null values in each column of the resulting DataFrame. The output shows the count of null values column-wise. to count null values column-wise: ``` df.isnull().sum() ``` ##Code snippet to count null values row-wise: ``` df.isnull().sum(axis=1) ``` In the above code, `df` is the Panda
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How to Use Help Command in HDFS

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Sometimes as a Hadoop developer it is difficult to remember all the Hadoop commands. The HELP command useful to know the correct syntax.

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How to List all HDFS Commands

hadoop
hadoop fs   ==> Enter

This will list all Hadoop commands.

Help Command in HDFS

Hadoop commands are the flavor of UNIX. If you want to see each Command description, you can go for Hadoop help command. You can use the below command for help.

hadoop fs -hlep ls 

Deleting a File in Hadoop HDFS

The below command helps   how to delete a file from Hadop cluster.

hadoop fs -rm exmaple.txt

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