Pairwise indexes from 1D array

pairwise_indexes.py

def pairwise_indexes(array, mode='comb'):
    """
    Get indexes pairwise from array
    
    Params:
        array(list or numpy.array): array with shape(N,) where N is array size
        mode: comb=combinatations or perm=permutations
        
    Returns:
        pairs(numpy.array): array with pair elements
    """
    import itertools as it
    import numpy as np
    
    array = np.array(array)
    
    if mode == 'comb':
        pairs = list(it.combinations(array, 2))
    elif mode == 'perm':
        pairs = list(it.permutations(array, 2))
    
    pairs = np.array(pairs)
    
    return pairs