[issue534669] remember to sync trees

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[issue35057] Email header refolding adds additional \r in nested parse trees

R. David Murray added the comment: Thank you for the report. This is a duplicate of #34424, which has a PR. -- resolution: -> duplicate stage: -> resolved status: open -> closed ___ Python tracker

[issue35057] Email header refolding adds additional \r in nested parse trees

New submission from Michael Thies : Email header refolding in email._header_value_parser adds additional carriage return symbols to the end of nested parse trees, when used with an EmailPolicy with linesep='\r\n'. This leads to broken email headers when composing an email with a "To:&qu

Re: loading trees...

On Monday, June 13, 2016 at 6:56:07 AM UTC+12, Fillmore wrote: > I then need to run a program that loads the whole forest in the form of a > dict() where each item will point to a dynamically loaded tree. Store it in JSON form? I like language-neutral solutions. --

Re: loading trees...

Fillmore <fillmore_rem...@hotmail.com> writes: > Hi, problem for today. I have a batch file that creates "trees of data". > I can save these trees in the form of python code or serialize them with > something > like pickle. > > I then need to run a program that

Re: loading trees...

h the data to the right tree for > further processing. > How do you determine which tree is suitable? Does it require knowledge of the whole tree? How big are the trees? How long does pickle take to load those trees? How frequently does data arrive? How long does it take you to determin

loading trees...

Hi, problem for today. I have a batch file that creates "trees of data". I can save these trees in the form of python code or serialize them with something like pickle. I then need to run a program that loads the whole forest in the form of a dict() where each item will point to a d

Re: Trees

On Thursday, January 22, 2015 at 12:46:22 PM UTC+5:30, Paul Rubin wrote: Ian Kelly writes: How do you create a tree containing an even number of elements under this constraint? That's a good point, I've usually seen different definitions of trees, e.g. data Tree a = Leaf | Branch

Re: Trees

On Wednesday, January 21, 2015 at 6:06:06 PM UTC+5:30, Chris Angelico wrote: On Wed, Jan 21, 2015 at 11:09 PM, Rustom Mody wrote: I would like a set to be {1,2,3} or at worst ⦃1,2,3⦄ and a bag to be ⟅1,2,3⟆ Apart from the unicode niceness that Ive described here

Re: Trees

On Wed, Jan 21, 2015 at 9:15 AM, Ian Kelly ian.g.ke...@gmail.com wrote: class MultiSet(MutableSet): In retrospect this probably shouldn't derive from MutableSet, since that carries the expectation that all elements are unique (much like how bool shouldn't be subclassed). For instance,

Re: Trees

On Wed, Jan 21, 2015 at 7:47 AM, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: More irksome that for the second we've to preface with from collections import Counter And still more a PITA that a straightforward standard name like bag (or multiset) is called by such an

Re: Trees

Rustom Mody rustompm...@gmail.com writes: Thats not bfs. That's inorder traversal Oops, you're right. How's this: bfs x = go [x] where go [] = [] go (L x:ts) = x:go ts go (B x lst rst:ts) = x : go (ts ++ [lst, rst]) *Main bfs t [6,2,8,1,4,7,9,3,5] --

Re: Trees

On Tue, Jan 20, 2015 at 6:23 PM, Rustom Mody rustompm...@gmail.com wrote: The Haskell is bullseye¹ in capturing the essense of a tree because conceptually a tree of type t is recursive in the sense that it can contain 2 subtrees -- (B x lst rst) -- or its a base case -- L x. How do you create

Re: Trees

not tried it 2. For n-ary trees its neater 3. In my imaginary language with first-class sets, bags, lists it would be neater still -- https://mail.python.org/mailman/listinfo/python-list

Re: Trees

On Thursday, January 22, 2015 at 4:25:03 AM UTC+5:30, Ian wrote: On Tue, Jan 20, 2015 at 6:23 PM, Rustom Mody wrote: The Haskell is bullseye¹ in capturing the essense of a tree because conceptually a tree of type t is recursive in the sense that it can contain 2 subtrees -- (B x lst rst) --

Re: Trees

of its children are empty trees? -- https://mail.python.org/mailman/listinfo/python-list

Re: Trees

On Wed, Jan 21, 2015 at 11:56 PM, Ian Kelly ian.g.ke...@gmail.com wrote: Since each element is associated with a node, the question could equally be phrased as How do you create a tree containing an even number of elements under this constraint? Of course I meant to write nodes there, not

Re: Trees

Ian Kelly ian.g.ke...@gmail.com writes: How do you create a tree containing an even number of elements under this constraint? That's a good point, I've usually seen different definitions of trees, e.g. data Tree a = Leaf | Branch a (Tree a) (Tree a) so a Leaf node doesn't have a value

Re: Trees

Stephen Hansen me+pyt...@ixokai.io: On Tue, Jan 20, 2015 at 1:45 AM, Marko Rauhamaa ma...@pacujo.net wrote: Terry Reedy tjre...@udel.edu: Others have answered as to why other special-purpose constrained-structure trees have not been added to the stdlib. Ordered O(log n) mappings

Re: Trees

, and a library (even the standard library) doesn't have to expose which one was picked as long as the performance is good. -- Devin On Tue, Jan 20, 2015 at 12:15 PM, Ken Seehart k...@seehart.com wrote: Exactly. There are over 23,000 different kinds of trees. There's no way you could get all of them to fit

Re: Trees

On Wed, Jan 21, 2015 at 11:55 PM, Tim Chase python.l...@tim.thechases.com wrote: On 2015-01-21 23:35, Chris Angelico wrote: On Wed, Jan 21, 2015 at 11:09 PM, Rustom Mody wrote Its a bit of a nuisance that we have to write set([1,2,3]) for the first Looks like {1,2,3} works for me. That

Re: Trees

On Wednesday, January 21, 2015 at 1:27:39 PM UTC+5:30, Stephen Hansen wrote: On Tue, Jan 20, 2015 at 1:45 AM, Marko Rauhamaa ma...@pacujo.net wrote: Terry Reedy tjr...@udel.edu: Others have answered as to why other special-purpose constrained-structure trees have not been added

Re: Trees

On 2015-01-21 23:35, Chris Angelico wrote: On Wed, Jan 21, 2015 at 11:09 PM, Rustom Mody wrote Its a bit of a nuisance that we have to write set([1,2,3]) for the first Wait, what? rosuav@sikorsky:~$ python Python 2.7.3 (default, Mar 13 2014, 11:03:55) [GCC 4.7.2] on linux2 Type help,

Re: Trees

On Wed, Jan 21, 2015 at 11:09 PM, Rustom Mody rustompm...@gmail.com wrote: I would like a set to be {1,2,3} or at worst ⦃1,2,3⦄ and a bag to be ⟅1,2,3⟆ Apart from the unicode niceness that Ive described here http://blog.languager.org/2014/04/unicoded-python.html Its a bit of a nuisance that

Re: Trees

On Thu, Jan 22, 2015 at 1:26 AM, Tim Chase python.l...@tim.thechases.com wrote: While 2.0 is certainly antiquated, Red Hat Enterprise Linux (RHEL) is often considered the best definition of what's considered oldest supported production environment. RHEL v4 ships with Py2.3 and one can still

Re: Trees

Rustom Mody wrote: On Wednesday, January 21, 2015 at 1:27:39 PM UTC+5:30, Stephen Hansen wrote: [...] Among my teachers of CS, there were two – both brilliant — one taught me Numerical Analysis, the other taught me programming. I wonder just how brilliant the Numerical Analysis guy really

Re: Trees

Hello Terry, It is not play with words. A tree is a recursive - nested - hierachical data structure with the restriction of no cycles or alternate pathways. Python collections whose members are general objects, including collections, can be nested. The resulting structures *are* tree

Re: Trees

On 2015-01-22 00:01, Chris Angelico wrote: On Wed, Jan 21, 2015 at 11:55 PM, Tim Chase Looks like {1,2,3} works for me. That hasn't always worked: the argument's still fairly weak when it's alongside a pipe-dream desire to use specific mathematical Unicode characters in source code,

Re: Trees

On Mon, Jan 19, 2015 at 11:52 PM, Devin Jeanpierre jeanpierr...@gmail.com wrote: On Mon, Jan 19, 2015 at 3:08 PM, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Possibly because they aren't needed

Re: Trees

Terry Reedy tjre...@udel.edu: Others have answered as to why other special-purpose constrained-structure trees have not been added to the stdlib. Ordered O(log n) mappings are not special-purpose data structures. I'd say strings and floats are much more special-purpose than ordered mappings

Re: Trees

On Tuesday, January 20, 2015 at 7:03:56 PM UTC+5:30, Rustom Mody wrote: On Tuesday, January 20, 2015 at 11:38:27 AM UTC+5:30, Terry Reedy wrote: On 1/19/2015 5:06 PM, Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Sequences nested withing sequences can

Re: Trees

On 20/01/2015 05:19, Marko Rauhamaa wrote: Mark Lawrence breamore...@yahoo.co.uk: On 19/01/2015 22:06, Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Probably because you'd never get agreement as to which specific tree and which specific implementation

Re: Trees

On Tuesday, January 20, 2015 at 7:46:02 PM UTC+5:30, Marko Rauhamaa wrote: Rustom Mody : Yeah python has trees alright. Does Python balance them for you? No Does python support a menagerie of lists like C - singly linked, doubly linked, with header, without header etc? Or access

Re: Trees

On Tuesday, January 20, 2015 at 11:38:27 AM UTC+5:30, Terry Reedy wrote: On 1/19/2015 5:06 PM, Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Sequences nested withing sequences can be regarded as trees, and Python has these. I regard Lisp as a tree

Re: Trees

On Mon, Jan 19, 2015 at 6:46 PM, Mark Lawrence breamore...@yahoo.co.uk wrote: I don't know if you've seen this http://kmike.ru/python-data-structures/ but maybe of interest. I haven't read but also possibly of interest: Data Structures and Algorithms in Python by Michael T. Goodrich, Roberto

Re: Trees

Rustom Mody rustompm...@gmail.com: Yeah python has trees alright. Does Python balance them for you? Marko -- https://mail.python.org/mailman/listinfo/python-list

Re: Trees

On Tue, Jan 20, 2015 at 6:33 AM, Rustom Mody rustompm...@gmail.com wrote: from enum import Enum class TreeTag(Enum): I = 0 # An internal node L = 1 # A leaf node def __repr__(self): return self.name I = TreeTag.I L = TreeTag.L Explicitly tagging nodes as internal or leaves

Re: Trees

Marko Rauhamaa ma...@pacujo.net writes: As I said, I use ordered mappings to implement timers... The downside of heapq is that canceled timers often flood the heapq structure..., GvR mentioned a periodic garbage collection as a potentially effective solution. You could look up the timer

Re: Trees

= TreeTag.L Explicitly tagging nodes as internal or leaves is kind of ugly and also prone to getting out of sync with the reality, which is that a node is a leaf if it doesn't have any other nodes hanging off of it. Yeah... Just demoing a technique for more variegated trees eg an AST for some toy

Re: Trees

On Tuesday, January 20, 2015 at 11:46:11 PM UTC+5:30, Rustom Mody wrote: On Tuesday, January 20, 2015 at 10:51:13 PM UTC+5:30, Ian wrote: On Tue, Jan 20, 2015 at 6:33 AM, Rustom Mody wrote: # Converting to generators is trivial = :-) Less trivial than I

Re: Trees

Marko Rauhamaa ma...@pacujo.net writes: So in my Python software (both at work and at home) needs, I use a Python AVL tree implementation of my own. My use case is timers. (GvR uses heapq for the purpose.) Have you benchmarked your version against heapq or even the builtin sorting functions?

Re: Trees

the tree structure is immutable and you insert or delete nodes in O(log n) operations, by creating new trees that share almost all their data with the old tree. Once you release the old root, garbage collection frees any nodes that were in the old tree but not the new one. Use case inspired by Haskell's

Re: Trees

Exactly. There are over 23,000 different kinds of trees. There's no way you could get all of them to fit in a library, especially a standard one. Instead, we prefer to provide people with the tools they need to grow their own trees. http://caseytrees.org/programs/planting/ctp/ http

Re: Trees

. -- Devin On Tue, Jan 20, 2015 at 12:15 PM, Ken Seehart k...@seehart.com wrote: Exactly. There are over 23,000 different kinds of trees. There's no way you could get all of them to fit in a library, especially a standard one. Instead, we prefer to provide people with the tools they need

Re: Trees

On Wed, Jan 21, 2015 at 7:15 AM, Ken Seehart k...@seehart.com wrote: Exactly. There are over 23,000 different kinds of trees. There's no way you could get all of them to fit in a library, especially a standard one. Instead, we prefer to provide people with the tools they need to grow their own

Re: Trees

On 20/01/15 01:49, Dan Stromberg wrote: I think probably the most common need for a tree is implementing a cache, That is probably true, at least if you're a squirrel. -- https://mail.python.org/mailman/listinfo/python-list

Re: Trees

In article d34dbfbe-fe82-47dc-8bc3-c8773e2b7...@googlegroups.com, rustompm...@gmail.com says... Yeah python has trees alright. Heres' some simple tree-code Didn't you just demonstrate that Python has no trees and instead you have to implement them yourself (or use a third-party

Re: Trees

Rustom Mody rustompm...@gmail.com writes: ## The depth first algorithm dfs (L x) = [x] dfs (B x lst rst) = [x] ++ dfs lst ++ dfs rst Cute. I can't resist posting the similar breadth first algorithm: bfs (L x) = [x] bfs (B x lst rst) = bfs lst ++ [x] ++ bfs rst *Main dfs t

Re: Trees

On Wednesday, January 21, 2015 at 7:19:39 AM UTC+5:30, Paul Rubin wrote: Rustom Mody writes: ## The depth first algorithm dfs (L x) = [x] dfs (B x lst rst) = [x] ++ dfs lst ++ dfs rst Cute. I can't resist posting the similar breadth first algorithm: bfs (L x) = [x] bfs (B x

Re: Trees

On 20 January 2015 at 04:21, Dan Stromberg drsali...@gmail.com wrote: On Mon, Jan 19, 2015 at 6:46 PM, Mark Lawrence breamore...@yahoo.co.uk wrote: I don't know if you've seen this http://kmike.ru/python-data-structures/ but maybe of interest. I've seen it. It's a nice page. I attempted

Re: Trees

On Wednesday, January 21, 2015 at 3:18:03 AM UTC+5:30, Mario wrote: rustompmody says... Yeah python has trees alright. Heres' some simple tree-code Didn't you just demonstrate that Python has no trees and instead you have to implement them yourself (or use a third-party

Re: Trees

On 21/01/2015 01:22, Joshua Landau wrote: On 20 January 2015 at 04:21, Dan Stromberg drsali...@gmail.com wrote: On Mon, Jan 19, 2015 at 6:46 PM, Mark Lawrence breamore...@yahoo.co.uk wrote: I don't know if you've seen this http://kmike.ru/python-data-structures/ but maybe of interest. I've

Re: Trees

On 1/20/2015 4:47 PM, Mario wrote: In article d34dbfbe-fe82-47dc-8bc3-c8773e2b7...@googlegroups.com, rustompm...@gmail.com says... Yeah python has trees alright. Heres' some simple tree-code Didn't you just demonstrate that Python has no trees and instead you have to implement them yourself

Re: Trees

On Tue, Jan 20, 2015 at 5:22 PM, Joshua Landau jos...@landau.ws wrote: On 20 January 2015 at 04:21, Dan Stromberg drsali...@gmail.com wrote: On Mon, Jan 19, 2015 at 6:46 PM, Mark Lawrence breamore...@yahoo.co.uk wrote: I don't know if you've seen this http://kmike.ru/python-data-structures/

Re: Trees

On Tue, Jan 20, 2015 at 1:45 AM, Marko Rauhamaa ma...@pacujo.net wrote: Terry Reedy tjre...@udel.edu: Others have answered as to why other special-purpose constrained-structure trees have not been added to the stdlib. Ordered O(log n) mappings are not special-purpose data structures. I'd

Re: Trees

Paul Rubin no.email@nospam.invalid: Marko Rauhamaa ma...@pacujo.net writes: So in my Python software (both at work and at home) needs, I use a Python AVL tree implementation of my own. My use case is timers. (GvR uses heapq for the purpose.) Have you benchmarked your version against heapq

Re: Trees

Paul Rubin no.email@nospam.invalid: You could look up the timer wheel approach used by the Linux kernel and by Erlang. It's less general than an ordered map, but probably faster in practice. https://lkml.org/lkml/2005/10/19/46 Has some info. I think the kernel uses a different method

Re: Trees

On 01/19/2015 04:08 PM, Steven D'Aprano wrote: Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Possibly because they aren't needed? Under what circumstances would you use a tree instead of a list or a dict or combination of both? That's not a rhetorical

Re: Trees

On Mon, Jan 19, 2015 at 3:08 PM, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Possibly because they aren't needed? Under what circumstances would you use a tree instead of a list or a dict

Re: Trees

On Mon, Jan 19, 2015 at 2:06 PM, Zachary Gilmartin zacharygilmar...@gmail.com wrote: Why aren't there trees in the python standard library? Trees are kind of specialized datastructures; no one type of tree solves all tree-related problems suitably well. I think probably the most common need

Re: Trees

On Mon, Jan 19, 2015 at 6:46 PM, Mark Lawrence breamore...@yahoo.co.uk wrote: On 20/01/2015 00:49, Dan Stromberg wrote: On Mon, Jan 19, 2015 at 2:06 PM, Zachary Gilmartin zacharygilmar...@gmail.com wrote: Why aren't there trees in the python standard library? Trees are kind of specialized

Re: Trees

Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Possibly because they aren't needed? Under what circumstances would you use a tree instead of a list or a dict or combination of both? That's not a rhetorical question. I am genuinely curious, what task do you have

Re: Trees

On 2015-01-19 16:19, Michael Torrie wrote: On 01/19/2015 04:08 PM, Steven D'Aprano wrote: Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Possibly because they aren't needed? Under what circumstances would you use a tree instead of a list or a dict

Re: Trees

On 19/01/2015 22:06, Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Probably because you'd never get agreement as to which specific tree and which specific implementation was the most suitable for inclusion. -- My fellow Pythonistas, ask not what our

Re: Trees

, Zachary Gilmartin zacharygilmar...@gmail.com wrote: Why aren't there trees in the python standard library? Trees are kind of specialized datastructures; no one type of tree solves all tree-related problems suitably well. I think probably the most common need for a tree

Re: Trees

In article mailman.17862.1421705173.18130.python-l...@python.org, zacharygilmar...@gmail.com says... Why aren't there trees in the python standard library? I don't know much about python development process and strategies, but I suspect it shouldn't be much different from any other language

Re: Trees

On 20/01/2015 00:49, Dan Stromberg wrote: On Mon, Jan 19, 2015 at 2:06 PM, Zachary Gilmartin zacharygilmar...@gmail.com wrote: Why aren't there trees in the python standard library? Trees are kind of specialized datastructures; no one type of tree solves all tree-related problems suitably

Re: Trees

On 1/19/2015 5:06 PM, Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Sequences nested withing sequences can be regarded as trees, and Python has these. I regard Lisp as a tree processing languages, as it must be to manipulate, for example, code with nested

Re: Trees

Mark Lawrence breamore...@yahoo.co.uk: On 19/01/2015 22:06, Zachary Gilmartin wrote: Why aren't there trees in the python standard library? Probably because you'd never get agreement as to which specific tree and which specific implementation was the most suitable for inclusion. Most

Trees

Why aren't there trees in the python standard library? -- https://mail.python.org/mailman/listinfo/python-list

Re: Trees

Zachary Gilmartin zacharygilmar...@gmail.com writes: Why aren't there trees in the python standard library? What sort of answer are you looking for? There are many ways that question could be intended. If you're asking about what could be keeping a particular tree implementation out

Re: Trees

On Tue, Jan 20, 2015 at 9:16 AM, Ben Finney ben+pyt...@benfinney.id.au wrote: If you're asking because you think all data structures magically appear in the standard library by wishing it so, I think you over-estimate the powers of the standard library maintainers. Oh come on Ben. Guido has a

Re: Balanced trees

discount the possibility of worst-case ordering. In fact, Dan himself said unbalanced trees performed so badly he couldn't test them satisfactorily. Marko -- https://mail.python.org/mailman/listinfo/python-list

Re: Balanced trees

performance. In fact, Dan himself said unbalanced trees performed so badly he couldn't test them satisfactorily. You're misrepresenting what Dan said. What he actually said was that unbalanced trees perform second only to dicts with random data, only with sorted data do they perform badly. His exact

Re: Balanced trees

Steven D'Aprano steve+comp.lang.pyt...@pearwood.info: Please re-read what I wrote. I didn't say if your data comes to you fully randomized. I said if you are in a position to randomize the data before storing it. In other words, if you actively randomize the data yourself. Yes, you could

Re: Balanced trees

are obviously not random, and using them as a keys in a balanced tree would give you sub-optimum performance. This is not a hypothetical scenario. Songza uses MongoDB as our database. The indexes are balanced trees. One of our biggest collections has a multi-component key, one of the components being

Re: Balanced trees

run against each data structure. How about this test program: I used to do essentially this, but it was time-prohibitive and produced harder-to-read graphs - harder to read because the enormous values of the bad trees were dwarfing the values of the good trees. A log graph may be the solution

Re: Balanced trees

On Tue, 18 Mar 2014 21:45:52 -, Dan Stromberg drsali...@gmail.com wrote: blist.sorteddict was able to do 65536 operations on a dictionary before taking more than 120 seconds to complete - it took 77.3 seconds to do 65536 operations. 65536 is a suspiciously round number. You might want

Re: Balanced trees

On Wed, Mar 19, 2014 at 7:16 PM, Rhodri James rho...@wildebst.org.uk wrote: 65536 is a suspiciously round number. You might want to double- check that there's no 16-bit overflow causing something unexpected. It's because I'm using powers of 2. All the numbers in the report are round in hex.

Re: Balanced trees

On 18 March 2014 01:01, Daniel Stutzbach stutzb...@google.com wrote: I would love to have include macro-benchmarks. I keep waiting for the PyPy benchmark suite to get ported to Python 3... *grins* Delete a slice is fudged from its inclusion of multiplication, which is far faster on blists.

Re: Balanced trees

On Mon, Mar 17, 2014 at 3:05 PM, Marko Rauhamaa ma...@pacujo.net wrote: Joshua Landau jos...@landau.ws: The thing we really need is for the blist containers to become stdlib (but not to replace the current list implementation). Very interesting. Downloaded blist but didn't compile it yet. It

Re: Balanced trees

Dan Stromberg drsali...@gmail.com: The results are at http://stromberg.dnsalias.org/~strombrg/python-tree-and-heap-comparison/2014-03/ Unfortunately I'm having a hard time understanding the results. The 50/50 get/set ratio is most interesting to me. I'm seeing (under cpython-3.3):

Re: Balanced trees

are in the dictionary. I used to run all the dictionaries for as long as it took to do 4 million operations, but for (EG) unbalanced binary trees, that would take far too long in the ordered tests, so I changed the code to try a given tree type until the time for an operation became prohibitive. If you

Re: Balanced trees

Dan Stromberg drsali...@gmail.com: dict was able to do 1048576 operations on a dictionary before taking more than 120 seconds to complete - it took 75.3 seconds to do 1048576 operations. AVL_tree was able to do 262144 operations on a dictionary before taking more than 120 seconds to

Re: Balanced trees

this, but it was time-prohibitive and produced harder-to-read graphs - harder to read because the enormous values of the bad trees were dwarfing the values of the good trees. Imagine doing 1 operation tests for the unbalanced binary tree. For a series of random keys, it would do quite well (probably

Re: Balanced trees

used to do essentially this, but it was time-prohibitive and produced harder-to-read graphs - harder to read because the enormous values of the bad trees were dwarfing the values of the good trees. Imagine doing 1 operation tests for the unbalanced binary tree. For a series of random

Re: Balanced trees

On Tue, Mar 18, 2014 at 1:55 PM, Marko Rauhamaa ma...@pacujo.net wrote: Dan Stromberg drsali...@gmail.com: The results are at http://stromberg.dnsalias.org/~strombrg/python-tree-and-heap-comparison/2014-03/ Size: 1048576, duration: 75.3, dictionary type: dict [...] Size:

Re: Balanced trees

On Wed, 19 Mar 2014 01:11:33 +0200, Marko Rauhamaa wrote: Dan Stromberg drsali...@gmail.com: Rather than throw out unbalanced binary tree altogether, it makes more sense to run it until it gets too slow. I disagree strongly. You should throw out unbalanced binary trees and linked lists

Re: Balanced trees

this test program: I used to do essentially this, but it was time-prohibitive and produced harder-to-read graphs - harder to read because the enormous values of the bad trees were dwarfing the values of the good trees. A log graph may be the solution to that: graph the log of the time rather

Re: Balanced trees

) *dst-- = *src--; Personally, I find it a bit odd to place lists at the center of the proposal and have trees come out as a side effect. I would rather see it the other way round: sorteddict - sortedset et al. * It reduces demand for trees: I would hope it would satisfy the demand

Re: Balanced trees

On 17 March 2014 21:16, Daniel Stutzbach stutzb...@google.com wrote: On Fri, Mar 14, 2014 at 6:13 PM, Joshua Landau jos...@landau.ws wrote: Now, I understand there are downsides to blist. Particularly, I've looked through the benchmarks and they seem untruthful. I worked hard to make those

blist in standard library (was Re: Balanced trees)

significant. This is very useful when considering usage as a multi-purpose data structure, and removes demand for explicit linked lists (which have foolishly been reimplemented loads of times). * It reduces demand for trees: * There are efficient implementations of sortedlist, sortedset

Re: Balanced trees

considering usage as a multi-purpose data structure, and removes demand for explicit linked lists (which have foolishly been reimplemented loads of times). * It reduces demand for trees: * There are efficient implementations of sortedlist, sortedset and sorteddict. * Slicing, slice assignment

Re: Balanced trees

On Mon, Mar 10, 2014 at 11:34 AM, Marko Rauhamaa ma...@pacujo.net wrote: The main thing is there are use cases where order is essential. That's why I have had to implement the AVL tree in Python myself. No biggie, but a C implementation would probably be much faster. Also, a standard version

Re: Balanced trees

On Mon, 10 Mar 2014 19:34:48 +0200, Marko Rauhamaa wrote: With a high level language like Python, using the provided hash table will almost always cream any hand-built tree, no matter how advantageous the data is to the tree. The main thing is there are use cases where order is essential.

Re: Balanced trees

On Thu, Mar 13, 2014 at 4:57 PM, Steven D'Aprano steve+comp.lang.pyt...@pearwood.info wrote: On Mon, 10 Mar 2014 19:34:48 +0200, Marko Rauhamaa wrote: With a high level language like Python, using the provided hash table will almost always cream any hand-built tree, no matter how advantageous

Re: Balanced trees

On Thu, 13 Mar 2014 20:12:41 -0700, Dan Stromberg wrote: Sorting the same (slightly tweaked) data inside of a tight loop is rarely a good idea - despite the fact that the sort itself tends to be O(n) with Python's rather awesome builtin sorting algorithm. This is because sorting inside a

Re: Balanced trees

Op 11-03-14 00:24, Roy Smith schreef: In article 8761nmrnfk@elektro.pacujo.net, Marko Rauhamaa ma...@pacujo.net wrote: Anyway, this whole debate is rather unnecessary since every developer is supposed to have both weapons in their arsenal. The problem with having a choice is that it

[issue13331] Packaging cannot install resource directory trees specified in setup.cfg

Éric Araujo added the comment: This is an issue for d2to1 / pbr / a new wheel PEP. -- resolution: - out of date stage: needs patch - committed/rejected status: open - closed ___ Python tracker rep...@bugs.python.org http://bugs.python.org/issue13331

Re: Balanced trees

On Mon, 10 Mar 2014 19:24:07 -0400, Roy Smith wrote: In article 8761nmrnfk@elektro.pacujo.net, Marko Rauhamaa ma...@pacujo.net wrote: Anyway, this whole debate is rather unnecessary since every developer is supposed to have both weapons in their arsenal. The problem with having a

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