Array Arithmetic and Broadcasting
In NumPy, you can perform math directly on arrays without writing loops.
This is called element-wise operations, and it is both fast and concise.
Array Arithmetic
When two arrays have the same size, NumPy applies operations element by element.
Array Arithmetic
a = np.array([1, 2, 3])
b = np.array([10, 20, 30])
print(a + b) # [11 22 33]
print(a * b) # [10 40 90]
You can also subtract, divide, or raise to powers: a - b, a / b, a ** 2
Broadcasting
When arrays are not the same shape, NumPy uses broadcasting to make them compatible.
This means smaller arrays are “stretched” so the operation can still work.
Broadcasting Example
a = np.array([1, 2, 3])
b = 10
print(a + b) # [11 12 13]
NumPy adds 10 to each element in a.
Broadcasting can also work between 2D and 1D arrays in many cases, which you will practice later.
Summary
- Use
+,-,*,/,**directly on arrays - Operations are applied element by element
- Broadcasting allows arrays of different shapes to work together
Want to learn more?
Join CodeFriends Plus membership or enroll in a course to start your journey.