how to save a modified .xml back
Hi all,
I want to load a small .xml file, modifiy some nodes and save the .xml with
modifications to another .xml file.
I managed to load and modify a small .xml file using xml.dom.minidom and
xml.dom.pulldom.
However, I don't know how to save it back using any of two modules.
Any suggestion?
Thank you in advance,
**
from xml.dom.pulldom import START_ELEMENT, parse
doc = parse('input.xml')
for event, node in doc:
if event == START_ELEMENT and node.localName == "something_interesting":
doc.expandNode(node)
for an_element in node.childNodes:
do_something()
*
Hyunchul
--
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Re: faster than list.extend()
Thank Tim, Raymond, and all. In my test, Tim's t1 was fastest and Raymond's triple3 is very near to Tim's t1. Anyway both of them took only 6~7% time of my original .extend() version. I think that following n_ple() is a good generalized function that was 1~3% slower than t1() and triple3() for "triple". * from itertools import * def n_ple(inputlist, n): chain_from_iterable = chain.from_iterable; izip = izip return chain_from_iterable(izip(*[inputlist]*n)) * def t2(i): r = range(3) return (x for x in i for _ in r) def t2_1(i): r = range(3) return [x for x in i for _ in r] I didn't know that list(t2(inputlist)) is much faster than t2_1(inputlist), it's gonna be a helpful tip for me. Thank you all. Hyunchul On Tue, Nov 17, 2009 at 7:55 AM, Tim Chase wrote: > Hyunchul Kim wrote: > >> Hi, all. >> >> I want to improve speed of following simple function. >> Any suggestion? >> >> ** >> def triple(inputlist): >> results = [] >> for x in inputlist: >>results.extend([x,x,x]) >> return results >> ** >> > > Several ways occur to me: > > def t1(i): >for x in i: > yield x > yield x > yield x > > def t2(i): >r = range(3) >return (x for x in i for _ in r) > > > I prefer to return generators in case the input is large, but in both > cases, you can just wrap it in list() like > > list(t1(inputlist)) > > or in t2(), you can just change it to use > >return [x for x in i for _ in r] > > -tkc > > > > > -- http://mail.python.org/mailman/listinfo/python-list
faster than list.extend()
Hi, all. I want to improve speed of following simple function. Any suggestion? ** def triple(inputlist): results = [] for x in inputlist: results.extend([x,x,x]) return results ** Thank you in advance, Hyunchul -- http://mail.python.org/mailman/listinfo/python-list
sequential multiple processes
Hi, all How to run multiple processes with sequential input of a thousand of data in a script run? I have a python script and 1,000 independent input data for it. Previously, I divided input data into* n* groups and ran a same python script *n* times to use *n* processors. It's inconvenient. How can I do same thing in a signle script running? Thank you in advance, Hyunchul -- http://mail.python.org/mailman/listinfo/python-list
speed of string chunks file parsing
Hi, all
I have a simple script.
Can you improve algorithm of following 10 line script, with a view point
of speed ?
Following script do exactly what I want but I want to improve the speed.
This parse a file and accumulate lines till a line match a given regular
expression.
Then, when a line match a given regular expression, this function yield
lines before the matched lines.
import re
resultlist = []
cp_regularexpression = re.compile('^a complex regular expression here$)
for line in file(inputfile):
if cp_regularexpression.match(line):
if resultlist != []:
yield resultlist
resultlist = []
resultlist.append(line)
yield resultlist
Thank you in advance,
Hyunchul
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http://mail.python.org/mailman/listinfo/python-list
Re: how to convert from Decimal('1.23456789') to Decimal('1.234')
In that case, I usually use # when rounding is proper, s = '1.23456789' print round(float(s)) or # when cut out is proper, from math import floor print floor(float(s)*1000)/1000 Hyunchul valpa wrote: I only need the 3 digits after '.' Is there any way other than converting from/to string? -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: unbiased benchmark
In the system that I tested, results were different. * System was CPU: AMD Phenom(tm) 9950 Quad-Core Processor, Frequency 2600MHz, L2 cache 512KB Memory 3164MB OS: Ubuntu 8.10 When I tried this benchmark for the first time, i...@pc:~$ time python bench.py real0m0.010s user0m0.008s sys0m0.000s i...@pc:~$ time ruby bench.rb real0m0.108s user0m0.000s sys0m0.004s Python was faster than Ruby 10 times!! As I repeated, results showed shorter times and became stable. After a few repeat, stable results were i...@pc:~$ time python bench.py real0m0.010s user0m0.008s sys0m0.000s i...@pc:~$ time ruby bench.rb real0m0.004s user0m0.004s sys0m0.000s Now, Ruby is faster two times. Have you repeated your benchmark? Your results looks to be over-exaggeration even if this benchmark is fair. Hyunchul Sam Ettessoc wrote: Dear sir, I would like to share a benchmark I did. The computer used was a 2160MHz Intel Core Duo w/ 2000MB of 667MHz DDR2 SDRAM running MAC OS 10.5.6 and a lots of software running (a typical developer workstation). Python benchmark: HAMBURGUESA:benchmark sam$ echo 1+1 > bench.py HAMBURGUESA:benchmark sam$ time python bench.py real0m0.064s user0m0.049s sys 0m0.013s Ruby benchmark: HAMBURGUESA:benchmark sam$ echo 1+1 > bench.rb HAMBURGUESA:benchmark sam$ time ruby bench.rb real0m0.006s user0m0.003s sys 0m0.003s Can you believe it? Ruby is 10 times faster than Python. On a side note, when I subscribed to the Python mailing list, it took less than 200ms before I got the confirmation email. For the Ruby mailing list, it took over 9000ms! Which is 4500% less performant! Sam Ettessoc p.s. I have no affiliation with ruby or python devloppement team. -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
Re: how to find all completely connected sub-graphs?
Dear Odeits, Yes, I meant directly connected to each other. Thanks. Hyunchul odeits wrote: On Mar 2, 10:35 pm, Hyunchul Kim wrote: Hi, all, How can I find all "completely connected subgraphs" in a graph when node and edge data are available? "completely connected subgraph" is a group, all members of which are connected to each other. Thanks, Hyunchul Do you mean all of the member are directly connected to each other? -- http://mail.python.org/mailman/listinfo/python-list -- http://mail.python.org/mailman/listinfo/python-list
how to find all completely connected sub-graphs?
Hi, all, How can I find all "completely connected subgraphs" in a graph when node and edge data are available? "completely connected subgraph" is a group, all members of which are connected to each other. Thanks, Hyunchul -- http://mail.python.org/mailman/listinfo/python-list
How to decompress .Z file?
Hi, all How can .Z file be decompressed? According to python library reference, .Z file might not be supported by python, yet. Best, Hyunchul Kim -- http://mail.python.org/mailman/listinfo/python-list
[python-list] pdf read & write
Dear all, How can I read a pdf file and add invisible comment? I want to make a script which read a pdf file and add tags inside the file invisibly. Then, I will make a script for managing tags of given pdf files. I know "referencer" can manage tags for pdf file but it seems store tag information to additional file outside pdf file. Any suggestion are welcome. Best, Hyunchul Kim -- http://mail.python.org/mailman/listinfo/python-list
[python-list] pdf read & write
Dear all, How can I read a pdf file and add invisible comment? I want to make a script which read a pdf file and add tags inside the file invisibly. Then, I will make a script for managing tags of given pdf files. I know "referencer" can manage tags for pdf file but it seems store tag information to additional file outside pdf file. Any suggestion are welcome. Best, Hyunchul Kim -- http://mail.python.org/mailman/listinfo/python-list
