Will - 10 months ago 37

Python Question

I have 4 individual numpy vectors with the shape (10, ), and I want to join them together to form a matrix (10, 4).

What is this transformation called?

Answer

It's called `stack`

.

```
> import numpy as np
> a = np.arange(10)
> b = np.stack((a, a, a, a), axis=1)
> np.shape(b)
(10, 4)
> b
array([[0, 0, 0, 0],
[1, 1, 1, 1],
[2, 2, 2, 2],
[3, 3, 3, 3],
[4, 4, 4, 4],
[5, 5, 5, 5],
[6, 6, 6, 6],
[7, 7, 7, 7],
[8, 8, 8, 8],
[9, 9, 9, 9]])
```

You could also (in this case) use e.g. `np.array([a, a, a, a]).T`

.

Source (Stackoverflow)