# How to Convert a 1D List to a 2D List in Python?

To convert a 1D list to a 2D list in Python, you can use list comprehension or nested loops to split the elements of the 1D list into separate rows of the 2D list. Here’s an example using list comprehension:

``````list_1d = [1, 2, 3, 4, 5, 6]
num_columns = 3

list_2d = [list_1d[i:i+num_columns] for i in range(0, len(list_1d), num_columns)]

print(list_2d)``````

In the code above, we have a 1D list called `list_1d` with elements `[1, 2, 3, 4, 5, 6]`. We also specify the number of columns for the resulting 2D list using `num_columns`.

Using list comprehension, we iterate over the `list_1d` and create slices of length `num_columns` starting from index `i` and incrementing `i` by `num_columns` in each iteration. This allows us to split the 1D list into rows of the desired length.

The resulting 2D list `list_2d` will have rows with `num_columns` elements, and any remaining elements will form the last row.

The output will be:

``[[1, 2, 3], [4, 5, 6]]``

In this example, the 1D list `[1, 2, 3, 4, 5, 6]` is converted to a 2D list with two rows and three columns.