Slow for big entries (SOLVED)

[GoogleCodeExporter]

What steps will reproduce the problem?
1. cat file | pyp "len(pp)"         # for a file with 500000 numbers
2.
3.

What is the expected output? What do you see instead?
the expected output is 500000

The problem is the method: def flatten_list(self, iterables)
it is recursive and does too many list manipulations.

I've rewritten it:

    def flatten_list(self, iterables):
        '''
        returns a list of strings from nested lists
        @param iterables: nested list to flatten
        @type iterables: list<str>
        '''
        out = []
        stack=[[iterables,0,len(iterables)]]
        while stack:
            curIter,pos,limit=stack[0]
            if pos==limit:
                stack.pop(0)
                continue
            if type(curIter[pos]) not in [str, PypStr]:
                stack[0][1]+=1
                stack.insert(0,[curIter[pos],0,len(curIter[pos])])
            else:
                out.append(curIter[pos])
                stack[0][1]+=1

        return out

Today is the first day I've used pyp, it's great but I've found this issue,
I think that would be great to make it faster, could anyone test this method
and maybe patch the source?

Thanks,
C

Original issue reported on code.google.com by deepbit on 16 Sep 2014 at 5:33

[GoogleCodeExporter]

awesome! can you post some speed tests? we'll test and put in if it works as 
expected. We're doing a bunch of stuff next month.

thanks!

Toby

Original comment by tobyro...@gmail.com on 16 Sep 2014 at 6:03

[GoogleCodeExporter]

$ for i in {0..100000}; do echo $i; done > /tmp/numbers
$ time cat numbers | pyp "len(pp)"
100001

real    1m27.045s
user    1m26.166s
sys 0m0.606s

(AFTER CODE PATCH)
$ time cat numbers | pyp "len(pp)"
100001

real    0m0.927s
user    0m0.871s
sys 0m0.050s

Best
C

Original comment by deepbit on 16 Sep 2014 at 9:12

[GoogleCodeExporter]

Because I haven't written complex PYP commands I am not sure wether the patch 
is completely bug free but I am pretty sure you can test it quickly.

Best
C

Original comment by deepbit on 16 Sep 2014 at 9:15

[GoogleCodeExporter]

wow, truly impressive...100 times faster.  We'll test this and get back with 
you.

thanks again!

t

Original comment by tobyro...@gmail.com on 16 Sep 2014 at 9:23

[GoogleCodeExporter]

testing this now. looks ok so far...going to release a big update to pyp 
including this...do you have any further revisions?

thanks!

toby

Original comment by tobyro...@gmail.com on 7 Feb 2015 at 12:17

[GoogleCodeExporter]

it looks like this works great for lists...increase speed by 100x...line by 
line speed is still the same...let me know if you have any ideas...

cheers,

toby

Original comment by tobyro...@gmail.com on 7 Feb 2015 at 1:09

[GoogleCodeExporter]

here is the latest if interested.  pretty close to releasing it.

Original comment by tobyro...@gmail.com on 7 Feb 2015 at 1:45

Attachments:

• pyp_dev_1.3