[Haskell-cafe] Optimizing queries in Haskell

2013-04-14 Thread Jan Stolarek
Dear list, list comprehensions and SQL-like generalized comprehensions can be used to write queries in Haskell. Does anyone know of any work focused on optimizing such queries? A quick google didn't show up anything meaningful. Janek ___ Haskell-Ca

[Haskell-cafe] yi-editor for emacer

2013-04-14 Thread Junior White
Hi Cafe, I'm glad to announce my fork of yi-editor. As a emacer, I made yi-editor more emacs like, including the following change: 1. ido-mode like file find and buffer find 2. support more color in vty 3. automatic search tags file in parents's directory 4. change some keymap The fol

Re: [Haskell-cafe] [Announcement] Sparse matrix Conjugate Gradient Solver

2013-04-14 Thread Daniel Díaz Casanueva
Nice! I will look at your implementation to see if I can learn something from this. :) On Sun, Apr 14, 2013 at 9:59 PM, Levent Erkok wrote: > I'm happy to announce the first release of conjugateGradient, implementing > the Conjugate Gradient algorithm for solving linear systems of equations > o

[Haskell-cafe] customizing haskeline?

2013-04-14 Thread Evan Laforge
I tried to colorize a haskeline prompt by putting control characters in it, but line editing was hopelessly confused, presumably because haskeline doesn't understand control characters and thought the prompt was longer than it really was. From looking at Haskeline.promptedInput, it seems like ther

Re: [Haskell-cafe] Building the Haskell Platform in Linux

2013-04-14 Thread Albert Y. C. Lai
On 13-04-14 08:12 PM, Daniel Díaz Casanueva wrote: By the way, a random question, what's the memory of the computer you used to build the Platform? I have always used my laptop with 3GB RAM. I have not measured how much is actually needed, or what happens if I provide less.

[Haskell-cafe] [Announcement] Sparse matrix Conjugate Gradient Solver

2013-04-14 Thread Levent Erkok
I'm happy to announce the first release of conjugateGradient, implementing the Conjugate Gradient algorithm for solving linear systems of equations over sparse matrices: http://hackage.haskell.org/package/conjugateGradient The conjugate gradient algorithm only applies to the cases when the in

Re: [Haskell-cafe] NaN as Integer value

2013-04-14 Thread Kim-Ee Yeoh
On Sun, Apr 14, 2013 at 3:28 PM, wren ng thornton wrote: > Whereas the problematic > values due to infinities are overspecified, so no matter which answer you > pick it's guaranteed to be the wrong answer half the time. > > Part of this whole problem comes from the fact that floats *do* decide to

Re: [Haskell-cafe] Building the Haskell Platform in Linux

2013-04-14 Thread Daniel Díaz Casanueva
Hello Albert! Oh! I didn't find that one when searching for info! That would have helped me a lot! By the way, a random question, what's the memory of the computer you used to build the Platform? On Sun, Apr 14, 2013 at 6:54 PM, Albert Y. C. Lai wrote: > On 13-04-13 12:19 AM, Daniel Díaz Casa

Re: [Haskell-cafe] Building the Haskell Platform in Linux

2013-04-14 Thread Albert Y. C. Lai
On 13-04-13 12:19 AM, Daniel Díaz Casanueva wrote: Hi cafe! Probably you all know how to do this, but I myself found confused when building the Haskell Platform in Linux for my first time. I was using Linux for my first time too! The first problem I encountered was to decide what linux packages

Re: [Haskell-cafe] multivariate normal distribution in Haskell?

2013-04-14 Thread Ben Gamari
Bas de Haas writes: > Dear List, > > I’m implementing a probabilistic model for recognising musical chords in > Haskell. This model relies on a multivariate normal distribution. I’ve > been searching the internet and mainly hackage for a Haskell library to > do this for me, but so far I’ve been u

[Haskell-cafe] Unbound: rebind and unrebind

2013-04-14 Thread Eric Dobson
I am working at reimplementing the library Unbound to understand how it works. One issue I have come up with is that an equation that I thought held true doesn't. The equation is: Forall e::Rebind a b, e `aeq` (uncurry rebind . unrebind $ e) => True. That is that spliting the binding of a rebind an

Re: [Haskell-cafe] multivariate normal distribution in Haskell?

2013-04-14 Thread Clark Gaebel
Is [1] what you're looking for (see the 'multinormal' function)? monte-carlo's pretty great... :) - Clark [1] http://hackage.haskell.org/packages/archive/monte-carlo/0.4.2/doc/html/Control-Monad-MC-Class.html#t:RNG On Sat, Apr 13, 2013 at 9:26 AM, Bas de Haas wrote: > Dear List, > > I’m im

Re: [Haskell-cafe] -inplace is shadowed by package -

2013-04-14 Thread Niklas Hambüchen
Hi, I just got the same thing with attoparsec GIT: Preprocessing benchmark 'benchmarks' for attoparsec-0.10.4.0... Building benchmark benchmarks... creating dist/build/benchmarks creating dist/build/benchmarks/benchmarks-tmp /home/niklas/opt/haskell-7.4/bin/ghc --make -fbuilding-cabal-package -O

[Haskell-cafe] Invitation to connect on LinkedIn

2013-04-14 Thread Chatura Roche
LinkedIn Chatura Roche requested to add you as a connection on LinkedIn: -- Steve, I'd like to add you to my professional network on LinkedIn. - Chatura Accept invitation from Chatura Roche http://www.linkedin.com/e/-j6322o-hfici7

Re: [Haskell-cafe] Fwd: [Haskell-beginners] Monad instances and type synonyms

2013-04-14 Thread Steffen Schuldenzucker
The point in not allowing partially applied type synonym instances is that it'd make deciding whether a type is an instance of a class much harder. Cf. here[1] for a similar question with the Category class. -- Steffen [1] Attached message. Couldn't find it on the archives.. On 04/14/2013 0

Re: [Haskell-cafe] Fwd: [Haskell-beginners] Monad instances and type synonyms

2013-04-14 Thread Daniil Frumin
Oh, I see that I'm late to the party, sorry, wasn't able to push my mail for some time  — On Sun, Apr 14, 2013 at 3:09 PM, Daniil Frumin wrote: > Maybe you can try "curried" definition: > type Adjustment = (->) SaleVariables > I had a similar problem awhile ago. > Hth > — > On Sun, Apr 14, 2013

Re: [Haskell-cafe] Fwd: [Haskell-beginners] Monad instances and type synonyms

2013-04-14 Thread Daniil Frumin
Maybe you can try "curried" definition: type Adjustment = (->) SaleVariables I had a similar problem awhile ago. Hth — On Sun, Apr 14, 2013 at 9:11 AM, Christopher Howard mailto:christopher.how...@frigidcode.com";>> wrote: I asked this question in Haskell-beginners, but I haven't heard a

Re: [Haskell-cafe] Fwd: [Haskell-beginners] Monad instances and type synonyms

2013-04-14 Thread Erik Hesselink
On Sun, Apr 14, 2013 at 9:28 AM, Chris Wong wrote: > On Sun, Apr 14, 2013 at 5:10 PM, Christopher Howard > wrote: >> type Adjustment a = SaleVariables -> a >> >> [...] >> >> instance Monad Adjustment where >> >> (>>=) = ... >> return = ... > > Essentially, you can't partially apply type synon

Re: [Haskell-cafe] Fwd: [Haskell-beginners] Monad instances and type synonyms

2013-04-14 Thread Johan Holmquist
It does not really make sense to make a type synonym an instance of some class, because a type synonym is just just what is says -- another name for some type. So making a type synonym for some type T an instance of a class would be the same as making T itself an instance of the class. Typically y

Re: [Haskell-cafe] NaN as Integer value

2013-04-14 Thread wren ng thornton
On 4/13/13 1:18 PM, Jerzy Karczmarczuk wrote: > This is not a Haskell problem. For Ints, ALL representations are valid > numbers, a NaN is a specific float object, unless I'm mistaken, so the > introduction of such an abnormal number would require some serious > modifications of the representation.

Re: [Haskell-cafe] Fwd: [Haskell-beginners] Monad instances and type synonyms

2013-04-14 Thread Chris Wong
On Sun, Apr 14, 2013 at 5:10 PM, Christopher Howard wrote: > type Adjustment a = SaleVariables -> a > > [...] > > instance Monad Adjustment where > > (>>=) = ... > return = ... Essentially, you can't partially apply type synonyms. I don't recall the exact reasoning, but if this sort of thing