Find numpy array with don't cares in a numpy array

I would like to find a numpy array with don’t cares like:

b = np.array(
    [
        [0,0,-1,-1]
    ]
    , dtype=np.int8
)

where -1 is the don’t care, and find it in arrays like:

a = np.array(
    [
        [1,2,0,0],
        [0,1,2,0],
        [0,0,1,2],
        [2,0,0,1],
        [3,4,0,0],
        [0,3,4,0],
        [0,0,3,4],
        [4,0,0,3]
    ]
    , dtype=np.int8
)

and return the row index’s 2 and 6 for the above sample

the a array are normally around 1000 rows shape(~1000, 4)

note the b array can have don’t cares any where or none, examples:

b = np.array(
    [
        [0,3,4,-1]
    ]
    , dtype=np.int8
)

# --OR--

b = np.array(
    [
        [2,-1,0,1]
    ]
    , dtype=np.int8
)

# --OR--

b = np.array(
    [
        [2,-1,-1,-1]
    ]
    , dtype=np.int8
)
# etc...

>Solution :

You could replace values in the main array with -1 where you have -1 in your sub array. Then you can just find where b==a

np.where(np.all(np.where((b==-1),-1,a)==b, axis=1))

Output

(array([2, 6], dtype=int64),)