从Python中的元组中减去元组的元组？

Question

我有一个元组的元组：

nums = ((4, 5, 6), (5, 6, 7), (2, 3)) 

现在我想创造一个每个数字是从“基准”数中减去一个类似的结构。对于元组的基准数字是：

baselines = (1, 0.5, 3) 

所以我想结构将是：

# want: diffs = ((3, 4, 5), (4.5, 5.5, 6.5), (-1, 0)) 

，我们有：

diffs[0] = [x - baselines[0] for x in nums[0]] 
diffs[1] = [x - baselines[1] for x in nums[1]] 
# etc. 

我怎样才能在Python这样做优雅？

Answer 1

使用zip与发电机的表达：

In [66]: nums = ((4, 5, 6), (5, 6, 7), (2, 3)) 

In [67]: baselines = (1, 0.5, 3) 

In [68]: tuple(tuple(val-y for val in x) for x,y in zip (nums,baselines)) 
Out[68]: ((3, 4, 5), (4.5, 5.5, 6.5), (-1, 0)) 

Answer 2

>>> [[x-baselines[i] for x in nums[i]] for i in range(3)] 
[[3, 4, 5], [4.5, 5.5, 6.5], [-1, 0]] 

你可以把它元组，像这样

>>> tuple(tuple(x-baselines[i] for x in nums[i]) for i in range(3)) 
((3, 4, 5), (4.5, 5.5, 6.5), (-1, 0))