在Python的列表理解中插入tkinter进度栏

Question

Normally i use a simple loop to insert a indeterminate progress bar in tkinter. example

self.pbar_ind = ttk.Progressbar(self, orient="horizontal", length=300, mode="indeterminate")

new_point_in_list = list()
for point in point_in_list:
  self.pbar_ind.step(1)
  self.update()
  if point > 2:
     new_point_in_list.append(point)

Now i am using a List Comprehensions to speed my computation

new_point_in_list = [point for point in point_in_list if point > 2]

i wish to know if it possible to insert in the List Comprehensions the Tkinter progress bar

Answer 1

If you are concerned about performance, remove the call to self.update() . It will slow your loop down by up to three orders of magnitude . At the very least you should call it only every 1,000 iterations or so.

In a quick test, I can do 10,000 simple calculations that result in 1% of the values being appended to a loop in about .0016 seconds. When I add a call to update in the loop, the time expands to 1.0148 seconds.

You said in a comment you have 80 million rows to iterate over. My same code can process 80 million calculations in 12 seconds , versus over 2 hours when I add in a call to update.

Converting your code to using a list comprehension will have a negligible effect compared to removing or reducing the calls to update.