What is fancy indexing in NumPy?

What is fancy indexing in NumPy?

Fancy indexing in NumPy allows you to access and modify array elements using arrays of indices.

Can you give me an example of fancy indexing?

Sure! If you have an array arr = np.array([10, 20, 30, 40, 50]), you can access elements using arr[[1, 3]] to get [20, 40].

What happens if I use fancy indexing on a 2D array?

In a 2D array, you can use two arrays of indices. For example, arr[[0, 1], [1, 0]] will return elements from the first row, second column and the second row, first column.

Are there any performance considerations with fancy indexing?

Yes, fancy indexing can be less efficient than regular indexing, especially for large arrays, as it creates copies of the data.