Python的矩陣，行和列

Question

我有一些問題矩陣：

b= [[-2.5, 0.5],  #b is random matrix 
    [-1.5, -0.5], 
    [-0.5, 0.5]] 

如何通過B獲得：

b=[[[-2.5], [0.5]], [[-1.5], [-0.5]], [[-0.5], [0.5]]] 

非常感謝

Answer 1

>>> b= [[-2.5, 0.5],  #b is random matrix 
    [-1.5, -0.5], 
    [-0.5, 0.5]] 
>>> [[[val] for val in row] for row in b] 
[[[-2.5], [0.5]], [[-1.5], [-0.5]], [[-0.5], [0.5]]] 

---

說明：考慮清單：

>>> oned = [1, 2, 3] 

你可以用一個列表理解重新創建：

>>> [val for val in oned] 
[1, 2, 3] 

然後只是包裝的每個元素在它自己的名單：

>>> [[val] for val in oned] 
[[1], [2], [3]] 

擴展，爲兩個維度。

Answer 2

Claudiu's answer可能更直接，但這是一個遞歸遍歷任何深度列表的列表的替代解決方案。

>>> listify = lambda x: map(listify, x) if isinstance(x, list) else [x] 
>>> listify(b) 
[[[-2.5], [0.5]], [[-1.5], [-0.5]], [[-0.5], [0.5]]]