Question

I have a rather simple question and I have found several answers to this question but I simply can’t get my head around it.

I have a list of x-values (for a plot) and a equally long list of y-values. I want to sort the list of y-values and update my x-list accordingly.
Suppose I have these lists

xVars = [1,2,3,4,5]
yVars = [9,7,1,3,5] 

After sorting this is the result I want:

xVars = [3,4,5,2,1]
yVars = [1,3,5,7,9] #this is now sorted

My point in doing this is that I want to plot the max y-values with the associated x-values.

I have encountered the itemgetter() function and the sorted(key=) but I understand neither (that is, they don’t work but thatś rather due to me not understanding them than it is because they wouldn’t work).

Many Thanks in advance!

EDIT: Many Thanks to all of you, I wish I could chose all of you as the correct answer but unfortunately I can. Your explanations have been very helpful and I have learned quite a bit more about python now. Thanks! 🙂

Answer 1

>>> tmp = sorted(zip(xVars, yVars),key=lambda x: x[1])
>>> xVars = [x[0] for x in tmp]
>>> yVars = [x[1] for x in tmp]
>>> xVars
[3, 4, 5, 2, 1]
>>> yVars
[1, 3, 5, 7, 9]