Hi,

Specifically I mean loops introduced in the labs,

```
cost = 0.
for i in range(m):
f_wb_i = np.dot(X[i], w) + b #(n,)(n,)=scalar, see np.dot
cost = cost + (f_wb_i - y[i])**2 #scalar
```

here, the dot product is used, however it is inside a loop. Is it possible to write this loop as a vector product?