How to use numpy.random.choice in a list of tuples?

Question

I need to do a random choice with a given probability for selecting a tuple from a list.

EDIT: The probabiliy for each tuple is in probabilit list I do not know forget the parameter replacement, by default is none The same problem using an array instead a list

The next sample code give me an error:

import numpy as np

probabilit = [0.333, 0.333, 0.333]
lista_elegir = [(3, 3), (3, 4), (3, 5)]

np.random.choice(lista_elegir, 1, probabilit)

And the error is:

ValueError: a must be 1-dimensional

How can i solve that?

Answer 1

According to the function's doc,

a : 1-D array-like or int
    If an ndarray, a random sample is generated from its elements.
    If an int, the random sample is generated as if a was np.arange(n)

So following that

lista_elegir[np.random.choice(len(lista_elegir),1,p=probabilit)]

should do what you want. (p= added as per comment; can omit if values are uniform).

It is choosing a number from [0,1,2], and then picking that element from your list.