`numpy.linalg:outer`

Signature

def outer ( x1 , x2 , / )

Compute the outer product of two vectors.

This function is Array API compatible. Compared to np.outer it accepts 1-dimensional inputs only.

x1 : (M,) array_like: One-dimensional input array of size N. Must have a numeric data type.
x2 : (N,) array_like: One-dimensional input array of size M. Must have a numeric data type.

Make a (*very* coarse) grid for computing a Mandelbrot set:

rl = np.linalg.outer(np.ones((5,)), np.linspace(-2, 2, 5))
rl
im = np.linalg.outer(1j*np.linspace(2, -2, 5), np.ones((5,)))
im
grid = rl + im
grid

✓

An example using a "vector" of letters:

x = np.array(['a', 'b', 'c'], dtype=object)
np.linalg.outer(x, [1, 2, 3])