Python：对列表列表进行排序

Question

I have a list of lists that looks something like this:

testList = 
[[(480.0, 349.0), (459.0, 354.0), (467.0, 343.0)] 
[(467.0, 343.0), (455.0, 344.0), (462.0, 334.0)] 
[(459.0, 354.0), (480.0, 349.0), (483.0, 366.0)] ...]

Each list represents triangles that I am trying to draw with a line. I have an unrelated drawing method that draws a line from first vertex to second to third and back to first vertex (thereby drawing a triangle). I also want to connect these triangles together without drawing new lines, and so I want to consecutively sequence the testList[i][0]s.

And so, I would like to reorder the vertices within the list AND testList , to something like this:

testList = 
[[(480.0, 349.0), (459.0, 354.0), (467.0, 343.0)] 
[(480.0, 349.0), (459.0, 354.0),  (483.0, 366.0)] 
[(467.0, 343.0), (455.0, 344.0), (462.0, 334.0)]...]

where testList[2] jumps up to testList[1] , and testList[1][0] and testList[1][1] switch.

Thanks to Alfonso Jiménez , here is the approach I have so far:

for subList in testList1:
    subList.sort()
testList1.sort()

which works pretty well, except I still do notice in the complete testList parts like:

...[(215.0, 737.0), (298.0, 633.0), (317.0, 660.0)]
[(317.0, 660.0), (333.0, 599.0), (394.0, 660.0)]
[(298.0, 633.0), (317.0, 660.0), (333.0, 599.0)]
[(282.0, 75.0), (316.0, 74.0), (336.0, 71.0)]...

that could be rearranged to have identical testList[i][0s] but don't (notice the (317.0, 660.0) vertex not moving to position [0]. You may see the complete output here

I am a beginner in python so any help would be incredibly appreciated. Thank you!

Answer 1

You question is little confusing, is this what you want :

I tried recursive approach , it will chuck and reorder 3-3 items from your list :

testList = [[(480.0, 349.0), (459.0, 354.0), (467.0, 343.0)],
[(467.0, 343.0), (455.0, 344.0), (462.0, 334.0)],
[(459.0, 354.0), (480.0, 349.0), (483.0, 366.0)]]
def  triangles(test_line):
    updated_list=[]
    if not test_line:
        return 0
    else:

        for index,item in enumerate(test_line[:3]):
            if index==0:
                updated_list.insert(index,test_line[index])
            if index==1:


                updated_list.insert(2,test_line[index])
            if index==2:
                test_line[index][0], test_line[index][1] = test_line[index][1], test_line[index][0]

                updated_list.insert(1,test_line[index])


        print(updated_list)
        return triangles(test_line[3:])

print(triangles(testList))

output:

[[(480.0, 349.0), (459.0, 354.0), (467.0, 343.0)], [(480.0, 349.0), (459.0, 354.0), (483.0, 366.0)], [(467.0, 343.0), (455.0, 344.0), (462.0, 334.0)]]

Test case with your updated long list:

testList = [[(480.0, 349.0), (459.0, 354.0), (467.0, 343.0)],
[(467.0, 343.0), (455.0, 344.0), (462.0, 334.0)],
[(459.0, 354.0), (480.0, 349.0), (483.0, 366.0)],
[(215.0, 737.0), (298.0, 633.0), (317.0, 660.0)],
[(317.0, 660.0), (333.0, 599.0), (394.0, 660.0)],
[(298.0, 633.0), (317.0, 660.0), (333.0, 599.0)]]

output:

[[(480.0, 349.0), (459.0, 354.0), (467.0, 343.0)], [(480.0, 349.0), (459.0, 354.0), (483.0, 366.0)], [(467.0, 343.0), (455.0, 344.0), (462.0, 334.0)]]
[[(215.0, 737.0), (298.0, 633.0), (317.0, 660.0)], [(317.0, 660.0), (298.0, 633.0), (333.0, 599.0)], [(317.0, 660.0), (333.0, 599.0), (394.0, 660.0)]]