Scripting: many single operations or few massive?

[eil]

Let's say i have 1000 files to move to folders by their dates. which variant will be faster?
- if script checks each files and moves that one to proper folder
- if script gathers a stack of files with similar date and then moves whole stack to proper folder
..or there is no difference?

[highend]

One command to gather every necessary information, loop over it and on each loop group items, move them and remove them from the pool -> Only as many loops as absolutely required...

[eil]

yep, that's second scenario, but is it really faster, that's what interests me?

[highend]

Em?

You have 1000 files, 20% have the same yyyy-mm-dd, 20% less loops. Ofc this is faster, 20% less move commands^^

[eil]

noob question again: what is the best algorithm for such gathering? i just can't understand how to compare items after they are gathered in variable.(or maybe it's wrong way and there is even better than comparing them one-by-one, say to get all items of similar date).

[highend]

formatlist() with an exclusion filter or regexreplace(), that are the two possibilites. I've used the latter mostly but XY got some speed improvements for really large datasets so that formatlist() is a viable option nowadays.

[eil]

formatlist() with an exclusion filter

get list of items > get date of first/any item > search for all items with similar date > save in variable(to do smt) > formatlist() with filter-exclude of those found > loop with "new smaller" list of items = smt like this?

[highend]

The loop surrounds this

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get date of first/any item > search for all items with similar date > save in variable(to do smt) > formatlist() with filter-exclude of those found

Use a while(true) loop and the first statement is a if (!$listOfItems) { break; }

[eil]

thanks for hints!

[highend]

search for all items with similar date > save in variable(to do smt)

You don't want to do that "search" everytime with a command like quicksearch(), do you?

You gather that information once before the loop and assign it to the "pool" variable.

Like:

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$pool = quicksearch(, "/fn", , "sm"); // Either only "m" or "sm" to see the progress as well

If it is really only a flat structure, report() with a template for modified date would work fine as well and does only contain the information that's necessary

[eil]

well basically with initial question i wanted to understand if i can modify script i was trying to do(or better to say you did) in this topic= viewtopic.php?f=7&t=21686
recently i used a lot, and as it checks file-by-file, say 16Gb of images took me ~15min of time to move them to proper date-folders. that's why i'm searching for a way to make it faster(gather same date items and then move them, seems like most there can be done).

[highend]

Where exactly is the problem now?

Pool of item(s) reducing loop.xys

Why did I use a regexmatches() to find all files with the same date? Because I don't want to match those that have a yyyy-mm-dd date in their path or name...
Something that formatlist() can't do for me...