从二维numpy数组创建具有'1'和'-1'元素的索引列表

Question

I created a 2D numpy array and introduced '1' and '-1' 's at random positions over iterations. Now, I want the list of the indices having those ones and minus ones. Here is my code:

import math
import numpy as np
import itertools

def function(
        250,
        10,
        50):


    crystal = np.zeros((250,250))

    defect_concentration = np.zeros(50)
    for k in range(50):


        i= np.random.randint(0,250-1,size =2)
        while crystal[i[0]][i[1]] != 0:
            i = np.random.randint(0,250-1,size =2)
        crystal[i[0]][i[1]] = -1
        j = np.random.randint(0,250-1,size =2)
        while crystal[j[0]][j[1]] !=0:
            j = np.random.randint(0,250-1,size =2)
        crystal[j[0]][j[1]] = 1 

        b = []
        c = []
        dist = math.sqrt(((i[0]-j[0])**2)+((i[1]-j[1])**2))

        if dist <= 10:
            crystal[i[0]][i[1]] = 0
            crystal[j[0]][j[1]] = 0

        else:    

            for x in range(len(crystal)):
                for y in range(len(crystal)):

                    if crystal[x][y] < 0:
                        b.append((x,y))
                     elif crystal[x][y] != 0:
                        c.append((x,y))

but, I am not getting the expected output.

b(1)

--------------------------------------------------------------------------- NameError Traceback (most recent call last) in () ----> 1 b(1)

NameError: name 'b' is not defined

Answer 1

This is not how you define a function:

def function(
        250,
        10,
        50):

You can clean up the crystal indexing:

In [512]: crystal[i[0]][i[1]]=10
In [513]: crystal[i[0]][i[1]]
Out[513]: 10.0

More idiomatic numpy :

In [514]: crystal[i[0], i[1]]
Out[514]: 10.0

or even

In [515]: crystal[tuple(i)]
Out[515]: 10.0

Since i is only 2 numbers these are equivalent, but soon or later the [...][...] style of indexing will bite you.