NumPy for ML: Tutorial 4

NumPy Tutorial 4

Concept: Math Without Loops

This is the "magic" of NumPy. In standard Python, you cannot add a number to a list directly (it causes an error). In NumPy, the number is "broadcast" to every item instantly.

Python List
data = [1, 2, 3]
data + 5
ERROR: Can only concatenate list to list.

NumPy Array
data = np.array([1, 2, 3])
print(data + 5)
Output: [6, 7, 8]

Activity: Match the Result

Drag the Python/NumPy operation on the left to the correct mathematical result on the right.

Operations:

np.array([2, 4]) * 2

np.array([10, 20]) + 5

np.array([10, 10]) / 2

Results:

Result: [15, 25]

Drop Addition Here

Result: [4, 8]

Drop Multiplication Here

Result: [5., 5.]

Drop Division Here

Knowledge Check

What happens if you run np.array([1, 2, 3]) * 0?

A. It deletes the array.

B. It returns [0, 0, 0].

C. It returns an Error.