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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

3 Best Methods to Read Files in Python

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Python supports three specific methods to read files- read, readline, readlines. All these you use on files. Each has its unique purpose. Below are the best examples. 3 Methods to read file read readline readlines Method-1: read It reads records from file in sequence. Here, file.txt is sample file with single row. file.txt abcdefghijk file_object.read(2) ==> you will get 'ab' file_object.read(4)  ===> you will get 'cdef' Here, the multiple read methods read the data in sequence. The read(x) method will read only the number of characters that mentioned in the read method. Again, if you give multiple read methods then it will read in sequence. Method-2: readline It reads the file line by line. Here, file.txt is a file with single row. file.txt abcdefghijk f ile_object.readline() ==> you will get ' abcdefghijk ' Here, it reads the file line by line. Method-3: readlines It reads all the records at a time. Here, file.txt is a file with two rows. file.txt ab