Re: [Haskell-cafe] Programming Chalenges: The 3n+1 problem
2011/4/14 Sebastian Fischer fisc...@nii.ac.jp The advantage of this complicated definition is that you get a memoized version of the `fibonacci` function simply by using `fixmemo` instead of `fix`: Wow. I think something about 'fix' just made sense thanks to your post, though I had read a few blog posts about it. David. ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Programming Chalenges: The 3n+1 problem
On Thu, Apr 14, 2011 at 8:02 PM, Luke Palmer lrpal...@gmail.com wrote: For this problem, it is too slow to memoize everything; you have to use a bounded memo table. That's why I use a combinator-based memo approach as opposed to the type-directed approach used in eg. MemoTrie. The memo table you need is something like switch (10^6) integral id I think because of the definition of `Data.Function.fix` fix f = let x = f x in x which uses sharing, the definition fibonacci = fix (switch (10^6) integral id . fib) chaches results even of independent global calls. If `fix` would be defined as fix f = f (fix f) it would only cache the recursive calls of each individual call. Do you agree? Here is a fixpoint combinator that is parameterized by a memo combinator: fixmemo :: Memo a - ((a - b) - (a - b)) - (a - b) fixmemo memo f = fix (memo . f) If I use fixmemo (switch (=10^6) integral id) collatz the computation of the maximum Collatz length between 1 and 10^6 takes around 16 seconds (rather than 4 seconds without memoization). But when using fixmemo (arrayRange (1,10^6)) collatz memoization actually pays off and run time goes down to around 3 seconds. I uploaded the program underlying my experiments to github (spoiler alert): https://gist.github.com/921469 I knew that memocombinators are more flexible than a type-based MemoTrie but it is nice to see that they also lead to more efficient implementations and allow to define the other array-based implementation from this thread in a modular way. Sebastian ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] build fails due to sem_close...
Hi all, I've got error listed below when I've tried to build ghc-7.0.2 on ppc64 arch. I 've tested patch from Debian (-pthread option) but this didn't fix the issue. Any idea what's wrong? Thanks for any tip/help. Jiri used packages: glibc: 2.12.90, 2.13.90 (tested for both) gcc: 4.6.0 I use these options for ppc64 arch in build.mk %ifarch ppc64 GhcUnregisterised=YES GhcWithNativeCodeGen=NO SplitObjs=NO GhcWithInterpreter=NO GhcNotThreaded=YES SRC_HC_OPTS+=-optc-mminimal-toc SRC_CC_OPTS+=-mminimal-toc -Wa,--noexecstack %endif error log: configure: Building in-tree ghc-pwd /usr/bin/ld: /usr/lib64/ghc-7.0.2/unix-2.4.2.0/libHSunix-2.4.2.0.a(Semaphore.o): undefined reference to symbol 'sem_close@@GLIBC_2.3' /usr/bin/ld: note: 'sem_close@@GLIBC_2.3' is defined in DSO /lib64/libpthread.so.0 so try adding it to the linker command line /lib64/libpthread.so.0: could not read symbols: Invalid operation collect2: ld returned 1 exit status configure: error: Building ghc-pwd failed ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] build fails due to sem_close...
Hi, Am Freitag, den 15.04.2011, 13:31 +0200 schrieb Jiri Skala: Hi all, I've got error listed below when I've tried to build ghc-7.0.2 on ppc64 arch. I 've tested patch from Debian (-pthread option) but this didn't fix the issue. Any idea what's wrong? Thanks for any tip/help. it should help :-). Have you run autoconf after changing configure.in, and have you rebuilt unix afterwards? We have: # ghc-pkg field unix extra-libraries extra-libraries: rt util dl pthread Greetings, Joachim -- Joachim nomeata Breitner mail: m...@joachim-breitner.de | ICQ# 74513189 | GPG-Key: 4743206C JID: nome...@joachim-breitner.de | http://www.joachim-breitner.de/ Debian Developer: nome...@debian.org signature.asc Description: This is a digitally signed message part ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Cairo and Haskell
Hi, I would like to use Haskell to generate automatically a poster. I guess that would be using Cairo so I can have a 2d canvas to draw in and maybe even preview before exporting to PDF. However, I can't find any documentation on Cairo with Haskell or any code examples related to what I want to do. Any suggestions? Cheers, -- PMatos ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Cairo and Haskell
Have a look at http://hackage.haskell.org/package/diagrams and http://hackage.haskell.org/package/Hieroglyph On Fri, Apr 15, 2011 at 2:54 PM, Paulo J. Matos pocma...@gmail.com wrote: Hi, I would like to use Haskell to generate automatically a poster. I guess that would be using Cairo so I can have a 2d canvas to draw in and maybe even preview before exporting to PDF. However, I can't find any documentation on Cairo with Haskell or any code examples related to what I want to do. Any suggestions? Cheers, -- PMatos ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Cairo and Haskell
Haskell has Cairo bindings as part of gtk2hs. The package on Hackage is called 'cairo'. You can certainly preview on the screen, but I'm less sure about exporting to PDF, since the bindings were intended for GUI programming. At least PNG output is possible, though; PDF may be, as well. http://hackage.haskell.org/package/cairo ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Cairo and Haskell
To answer my own email, yes, PDF support is there. On Apr 15, 2011 8:17 AM, Chris Smith cdsm...@gmail.com wrote: Haskell has Cairo bindings as part of gtk2hs. The package on Hackage is called 'cairo'. You can certainly preview on the screen, but I'm less sure about exporting to PDF, since the bindings were intended for GUI programming. At least PNG output is possible, though; PDF may be, as well. http://hackage.haskell.org/package/cairo ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] timsort
hello -- has anyone every implemented (and benchmarked) timsort in haskell? http://bugs.python.org/file4451/timsort.txt it is a stable mergesort-like algorithm, seems like a good fit for haskell. best, ben ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Cairo and Haskell
On Fri, Apr 15, 2011 at 08:19:02AM -0600, Chris Smith wrote: On Apr 15, 2011 8:17 AM, Chris Smith cdsm...@gmail.com wrote: Haskell has Cairo bindings as part of gtk2hs. The package on Hackage is called 'cairo'. You can certainly preview on the screen, but I'm less sure about exporting to PDF, since the bindings were intended for GUI programming. At least PNG output is possible, though; PDF may be, as well. To answer my own email, yes, PDF support is there. You can also take a look at the demo programs in the cairo package: bash $ mkdir /tmp/uncabal cd /tmp/uncabal bash $ cabal unpack cairo bash $ cd /tmp/uncabal/cairo-*/demo bash $ runghc StarAndRing.hs The gtk2hs bindings are generaly pretty dumb and just mimic the original C behaviour. So the best source of documentation is the original cairo website: http://cairographics.org/documentation/ regards, /john ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] timsort
On Friday 15 April 2011 16:42:22, Ben wrote: hello -- has anyone every implemented (and benchmarked) timsort in haskell? http://bugs.python.org/file4451/timsort.txt it is a stable mergesort-like algorithm, seems like a good fit for haskell. best, ben From a short look, it seems similar to the algorithm used in Data.List.sort (except for the minrun stuff, which I think is not much of a concern for linked lists). ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Cairo and Haskell
Thanks I will take a look at those. On 15/04/11 15:12, Robert Wills wrote: Have a look at http://hackage.haskell.org/package/diagrams and http://hackage.haskell.org/package/Hieroglyph ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Cairo and Haskell
On 15/04/11 15:19, Chris Smith wrote: To answer my own email, yes, PDF support is there. Great, I assume it would also allow me to preview it on a GTK canvas, right? -- PMatos ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Cairo and Haskell
On 15/04/11 16:13, John Obbele wrote: bash $ mkdir /tmp/uncabal cd /tmp/uncabal bash $ cabal unpack cairo bash $ cd /tmp/uncabal/cairo-*/demo bash $ runghc StarAndRing.hs The gtk2hs bindings are generaly pretty dumb and just mimic the original C behaviour. So the best source of documentation is the original cairo website: http://cairographics.org/documentation/ Awesome, just tried it and it worked! Will start off based on that! :) -- PMatos ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] ANN: bindings to xfconf-4.8.0.0
Hi all, I'm very happy to announce my first hackageDB package: xfconf[0], a Haskell binding to the XFCE xfconfd configuration dæmon. It's mainly a pet project I have done to learn Haskell using the FFI and QuickCheck but if someone can find it useful or instructive I would be happy. This package allows easy access to your favorite XFCE desktop settings (wallpaper, colors, police, etc.) and easier synchronisations between the configuration backend and your own Gtk+2 widget properties (a feature missing in gconf but now part of gsettings). A practical use of this binding can be found in hThemes[1], a quickdirty front-end to switch between pre-defined desktop themes (eg. switching from a light-white theme for daytime to a dark-black one for your nightly hack sessions). [0.a]: http://hackage.haskell.org/package/xfconf [0.b]: http://patch-tag.com/r/obbele/xfconf/home [1]: http://patch-tag.com/r/obbele/hThemes/home Thanks to Andy Stewart and Axel Simon for their help in integrating xfconf to the gtk2hs stack. Any comments on this first work are welcomed ,-) regards, /John ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] Haskell Platform 2011.2.0.1 now available
We're pleased to announce the 2011.2.0.1 release of the Haskell Platform: a single, standard Haskell distribution for everyone. Download the Haskell Platform 2011.2.0.1: http://haskell.org/platform/ This release adds support for GHC 7.0.3, and significant improvements for Mac OS X users. The specification, along with installers (including Windows, Mac and Unix installers for a full Haskell environment) are available. The Haskell Platform is a single, standard Haskell distribution for every system, in the form of a blessed library and tool suite for Haskell distilled from the thousands of libraries on Hackage, along with installers for a wide variety of systems. It saves developers work picking and choosing the best Haskell libraries and tools to use for a task. When you install the Haskell Platform, you get the latest stable compiler, an expanded set of core libraries, additional development tools, and cabal-install – so you can download anything else you need from Hackage. This release ships with GHC 7.0.3. What you get is specified here: http://hackage.haskell.org/platform/contents.html Thanks! -- The Platform Infrastructure Team P.S. a big thanks to Mark Lentczner and Mikhail Glushenkov who built the Mac and Windows installers! ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell Platform 2011.2.0.1 now available
This release adds support for GHC 7.0.3, and significant improvements for Mac OS X users. Enticing! What are these significant improvements for Mac OS X users? - Conal On Fri, Apr 15, 2011 at 3:44 PM, Don Stewart don...@gmail.com wrote: We're pleased to announce the 2011.2.0.1 release of the Haskell Platform: a single, standard Haskell distribution for everyone. Download the Haskell Platform 2011.2.0.1: http://haskell.org/platform/ This release adds support for GHC 7.0.3, and significant improvements for Mac OS X users. The specification, along with installers (including Windows, Mac and Unix installers for a full Haskell environment) are available. The Haskell Platform is a single, standard Haskell distribution for every system, in the form of a blessed library and tool suite for Haskell distilled from the thousands of libraries on Hackage, along with installers for a wide variety of systems. It saves developers work picking and choosing the best Haskell libraries and tools to use for a task. When you install the Haskell Platform, you get the latest stable compiler, an expanded set of core libraries, additional development tools, and cabal-install – so you can download anything else you need from Hackage. This release ships with GHC 7.0.3. What you get is specified here: http://hackage.haskell.org/platform/contents.html Thanks! -- The Platform Infrastructure Team P.S. a big thanks to Mark Lentczner and Mikhail Glushenkov who built the Mac and Windows installers! ___ Libraries mailing list librar...@haskell.org http://www.haskell.org/mailman/listinfo/libraries ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
[Haskell-cafe] 64 bit generic link warning on every compile
GHC 7 compiles fine, but there's an additional warning during linking. $ system_profiler SPSoftwareDataType | grep System Version System Version: Mac OS X 10.6.7 (10J869) $ ghc --version The Glorious Glasgow Haskell Compilation System, version 7.0.2 $ cat hello.hs #!/usr/bin/env runhaskell module Main where main :: IO () main = putStrLn Hello World $ ghc --make hello.hs [1 of 1] Compiling Main ( hello.hs, hello.o ) Linking hello ... ld: warning: -read_only_relocs cannot be used with x86_64 $ ./hello Hello World Cheers, Andrew Pennebaker www.yellosoft.us ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] Haskell Platform 2011.2.0.1 now available
XCode 4 works, amongst other things: http://www.haskell.org/ghc/docs/7.0.3/html/users_guide/release-7-0-3.html Cheers, Don On Fri, Apr 15, 2011 at 7:15 PM, Conal Elliott co...@conal.net wrote: This release adds support for GHC 7.0.3, and significant improvements for Mac OS X users. Enticing! What are these significant improvements for Mac OS X users? - Conal On Fri, Apr 15, 2011 at 3:44 PM, Don Stewart don...@gmail.com wrote: We're pleased to announce the 2011.2.0.1 release of the Haskell Platform: a single, standard Haskell distribution for everyone. Download the Haskell Platform 2011.2.0.1: http://haskell.org/platform/ This release adds support for GHC 7.0.3, and significant improvements for Mac OS X users. The specification, along with installers (including Windows, Mac and Unix installers for a full Haskell environment) are available. The Haskell Platform is a single, standard Haskell distribution for every system, in the form of a blessed library and tool suite for Haskell distilled from the thousands of libraries on Hackage, along with installers for a wide variety of systems. It saves developers work picking and choosing the best Haskell libraries and tools to use for a task. When you install the Haskell Platform, you get the latest stable compiler, an expanded set of core libraries, additional development tools, and cabal-install – so you can download anything else you need from Hackage. This release ships with GHC 7.0.3. What you get is specified here: http://hackage.haskell.org/platform/contents.html Thanks! -- The Platform Infrastructure Team P.S. a big thanks to Mark Lentczner and Mikhail Glushenkov who built the Mac and Windows installers! ___ Libraries mailing list librar...@haskell.org http://www.haskell.org/mailman/listinfo/libraries ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
Re: [Haskell-cafe] 64 bit generic link warning on every compile
I get this too. I've heard that it is resolved in 7.0.3 but I can't recall where. (System Version: Mac OS X 10.6.7 (10J869), The Glorious Glasgow Haskell Compilation System, version 7.0.2) On Sat, Apr 16, 2011 at 10:47 AM, Andrew Pennebaker andrew.penneba...@gmail.com wrote: GHC 7 compiles fine, but there's an additional warning during linking. $ system_profiler SPSoftwareDataType | grep System Version System Version: Mac OS X 10.6.7 (10J869) $ ghc --version The Glorious Glasgow Haskell Compilation System, version 7.0.2 $ cat hello.hs #!/usr/bin/env runhaskell module Main where main :: IO () main = putStrLn Hello World $ ghc --make hello.hs [1 of 1] Compiling Main ( hello.hs, hello.o ) Linking hello ... ld: warning: -read_only_relocs cannot be used with x86_64 $ ./hello Hello World Cheers, Andrew Pennebaker www.yellosoft.us ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe ___ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
