# Replacing diagonals with zero

In this thread, we will discuss different ways of replacing the diagonals of DataFrame with 0. Replacing the diagonal with zero can be used for many reasons. A few common applications are:

• To identify clusters or communities of nodes that are strongly connected to each other during network analysis.
• To remove any bias or `noise` that may be present in the data.

There are various methods that can be used to replace both diagonals of a Pandas DataFrame with zeros:

#### 1. Using the "NumPy" function:

One of the easiest ways to replace both diagonals of a Pandas DataFrame with zeros involves using the fill_diagonal() function from NumPy. This function is capable of setting the values of the diagonal of a 2D array to any given value. To accomplish this, you can first convert the DataFrame to a NumPy array by accessing its values attribute. Then, you can apply fill_diagonal() to the array to replace both diagonals with zeros. Finally, you can create a new DataFrame using the pd.DataFrame() constructor to convert the modified array back to a DataFrame.

#### 2. Using the "diagonal()" method:

Another way to replace both diagonals of a Pandas DataFrame with zeros is to use the `diagonal()` method of NumPy arrays. This method returns a copy of the specified diagonal of a `2D array`. You can use this method to replace both diagonals of your DataFrame with zeros by iterating over the rows of the DataFrame and replacing the values on the diagonal with zeros.

#### 3. Using the "apply()" method:

Another way to replace both diagonals of a Pandas DataFrame with zeros is to use the `apply()` method. You can define a custom function that replaces the diagonal of a row with zeros, and then apply this function to each row of the DataFrame using `apply()` .