One-Hot Encode Categories

Convert categorical labels into a binary indicator matrix with one column per category, in the order given by categories.

Implement solve(values, categories).

Returns. Return an integer NumPy array of shape (len(values), len(categories)). A label that is not in categories raises KeyError.

Examples

Example 1

Input:

solve(['a', 'c', 'b'], ['a', 'b', 'c'])

Output:

[[1, 0, 0], [0, 0, 1], [0, 1, 0]]

Example 2

Input:

solve(['x', 'x'], ['x', 'y'])

Output:

[[1, 0], [1, 0]]