**NumPy Library **

NumPy is a library in python that is created to work efficiently with arrays in python. It is fast, easy to learn, and provides efficient storage. It also provides a better way of handling data for the process. We can create an n-dimensional array in NumPy. To use NumPy simply have to import it in our program and then we can easily use the functionality of NumPy in our program.

NumPy is a Python library that is frequently used for scientific and statistical analysis. NumPy arrays are grids of the same datatype’s values.

**Numpy matrix.trace() Function:**

We can find the sum of all the diagonal elements of a matrix using the matrix.trace() method of the Numpy module.

**Syntax:**

matrix.trace()

**Return Value:**

The sum of all the diagonal elements of a given matrix is returned by the trace() function.

## Numpy matrix.trace() Function in Python

**For 2-Dimensional (2D) Matrix**

**Approach:**

- Import numpy module using the import keyword
- Create a matrix(2-Dimensional) using the matrix() function of numpy module by passing some random 2D matrix as an argument to it and store it in a variable
- Apply trace() function on the given matrix to get the sum of all the diagonal elements of a given matrix
- Store it in another variable
- Print the sum of all the diagonal elements of a given matrix.
- The Exit of the Program.

**Below is the implementation:**

# Import numpy module using the import keyword import numpy as np # Create a matrix(2-Dimensional) using the matrix() function of numpy module by passing # some random 2D matrix as an argument to it and store it in a variable gvn_matrx = np.matrix('[2, 1; 6, 3]') # Apply trace() function on the given matrix to get the sum of all the diagonal # elements of a given matrix # Store it in another variable rslt = gvn_matrx.trace() # Print the sum of all the diagonal elements of a given matrix print("The sum of all the diagonal elements of a given matrix:") print(rslt)

**Output:**

The sum of all the diagonal elements of a given matrix: [[5]]

**For 3-Dimensional (3D) Matrix**

**Approach:**

- Import numpy module using the import keyword
- Create a matrix(3-Dimensional) using the matrix() function of numpy module by passing some random 3D matrix as an argument to it and store it in a variable
- Apply trace() function on the given matrix to get the sum of all the diagonal elements of a given matrix
- Store it in another variable
- Print the sum of all the diagonal elements of a given matrix.
- The Exit of the Program.

**Below is the implementation:**

# Import numpy module using the import keyword import numpy as np # Create a matrix(3-Dimensional) using the matrix() function of numpy module by passing # some random 3D matrix as an argument to it and store it in a variable gvn_matrx = np.matrix('[2, 4, 1; 8, 7, 3; 10, 9, 5]') # Apply trace() function on the given matrix to get the sum of all the diagonal # elements of a given matrix # Store it in another variable rslt = gvn_matrx.trace() # Print the sum of all the diagonal elements of a given matrix print("The sum of all the diagonal elements of a given matrix:") print(rslt)

**Output:**

The sum of all the diagonal elements of a given matrix: [[14]]