python 2d数组到dict [英] python 2d array to dict

问题描述

我想创建一个表示为2d数组的对称矩阵的下三角形的dict。例如，如果numpy数组是;

I want to create a dict from lower triangle of a symmetric matrix represented as 2d array. For examples if the numpy array is;

array([[0, 2, 3],
       [2, 0, 4],
       [3, 4, 0]])

然后我想字体看起来像;

then I want the dict to look like;

{('1', '0'): 2, ('2', '0'): 3, ('2', '1'): 4}

post for vector;

There is a similar post for vector;

Fastest way to convert a Numpy array into a sparse dictionary?

我比较新的python所以任何帮助/ suggestoins赞赏。

I am relatively new to python so any help/suggestoins appreciated.

推荐答案

>>> arr =[[0, 2, 3],
          [2, 0, 4],
          [3, 4, 0]]
>>> dict(((j,i), arr[i][j]) for i in range(len(arr)) for j in range(len(arr[0])) if i<j)
{(2, 0): 3, (1, 0): 2, (2, 1): 4}

这篇关于python 2d数组到dict的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！