create second column in matrix in python

To create a second column in a matrix in Python, you can either create a new matrix with the desired values in the second column or you can modify an existing matrix to add a second column.

Here's an example of creating a new matrix with a second column:

main.py
# Create a matrix with a single column
matrix = [[1], [2], [3]]

# Create a new matrix with a second column
new_matrix = [[row[0], 0] for row in matrix]

print(new_matrix)
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Output:

main.py
[[1, 0], [2, 0], [3, 0]]
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2 lines

In this example, we iterate over each row in the original matrix and create a new row in the new matrix with the values from the original row in the first column and a value of 0 in the second column.

If you want to modify an existing matrix to add a second column, you can use the following code:

main.py
# Modify an existing matrix to add a second column
matrix = [[1], [2], [3]]

for row in matrix:
    row.append(0)

print(matrix)
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Output:

main.py
[[1, 0], [2, 0], [3, 0]]
25 chars
2 lines

In this example, we iterate over each row in the matrix and use the .append() method to add a value of 0 to the end of each row, effectively adding a second column.

Remember to modify the code according to your specific requirements and data.