Python中的2D对象数组

我正在将一些
java代码转换为python代码,我最终难以理解如何将
Java中的2D对象数组转换为python.

Java代码：

private Node nodes[][] = new Node[rows][columns];

我怎么能在python中这样做？

解决方法

我想这就是你想要的

nodes = [[Node() for j in range(cols)] for i in range(rows)]

但是,初始化列表并不总是一个好习惯.对于矩阵,它可能是有道理的.

如果你想知道：关于list comprehensions的文档

演示代码：

>>> class Node:
      def __repr__(self):
        return "Node: %s" % id(self)
>>> cols = 3
>>> rows = 4
>>> nodes = [[Node() for j in range(cols)] for i in range(rows)]
>>> from pprint import pprint
>>> pprint(nodes)
[[Node: 41596976,Node: 41597048,Node: 41596904],[Node: 41597120,Node: 41597192,Node: 41597336],[Node: 41597552,Node: 41597624,Node: 41597696],[Node: 41597768,Node: 41597840,Node: 41597912]]