Python: Sort list with parallel list

Question

I have a list that is filled with HTML elements. I also have a list filled with date/times, which is parallel to the HTML list.

How can I sort the HTML list based on the time/date list? The time/date is in a timestamp format.

Answer 1

You can use zip.

timestamps, elements = zip(*sorted(zip(timestamps, elements)))

The result will be two tuples which you can convert to lists if you prefer.

Answer 2

Zip the two lists up into tuples, sort, then take the HTML back out of the tuple:

zipped = zip(timestamps, htmls)
zipped.sort()
sorted_htmls = [html for (timestamp, html) in zipped]

Answer 3

Enumerate will give you a list of (index,item) tuples for each item in the list. You can sort this using the index to read the sort key from the timestamps list. Then peel off the html elements:

sorted_elems = [elem for i,elem in sorted(enumerate(html_elements), 
                                          key=lambda x:timestamps[x[0]])]

What could be simpler?