def drop_entry(data, p):
    for i in range(len(data)):
        for j in range(len(data[i])):
            if (np.random.random_sample() < p):
                data[i][j] = 0
            else:
                data[i][j] = data[i][j]
    return data
def drop_entry(data, p):
    for i in range(len(data)):
        for j in range(len(data[i])):
            if (np.random.random_sample() < p):
                data[i][j] = 0
            else:
                data[i][j] = data[i][j]
    return data