===
Vacancy PhD student on Real-life datatype-generic programming
Software Technology,
Utrecht University,
The Netherlands.
===
Within the Software Technology group of the Information and Computing
L.Guo wrote:
Hi all:
I already have one matrix of type [[a]] to store one image.
What I want to do is to devide the image into severial small blocks in same
size.
In the sense of dividing an image like
abcd
efgh
ijkl
mnop
into the sequence of images
[
ab
ef
,
cd
gh
,
ij
mn
,
kl
op
]
Henning Thielemann wrote:
On Wed, 13 Jun 2007, L.Guo wrote:
I already have one matrix of type [[a]] to store one image.
What I want to do is to devide the image into severial small blocks in same
size.
To do that, I wrote this tool function.
chop :: Int - [a] - [[a]]
chop _ [] = []
On Wed, 13 Jun 2007, L.Guo wrote:
I already have one matrix of type [[a]] to store one image.
What I want to do is to devide the image into severial small blocks in same
size.
To do that, I wrote this tool function.
chop :: Int - [a] - [[a]]
chop _ [] = []
chop n ls = take n ls :
[Moved to haskell-cafe]
Daniel Mahler schrieb:
Given your reservation regarding LLVM,
you may be interested in vmgen, developed and used as a part of gforth.
It is also claimed that a JVM built with vmgen had performance comparable
to state of the art JITs.
If I remember the author of both
Andrew Coppin wrote:
I'm trying to construct a function
all_trees :: [Int] - [Tree]
such that all_trees [1,2,3] will yield
[
Leaf 1,
Leaf 2,
Leaf 3,
Branch (Leaf 1) (Leaf 2),
Branch (Leaf 1) (Leaf 3),
Branch (Leaf 2) (Leaf 1),
Branch (Leaf 2) (Leaf 3),
Branch (Leaf 3) (Leaf 1),
Hello Malcolm,
Wednesday, June 13, 2007, 1:55:43 PM, you wrote:
In addition, we are in the process of setting up a separate server called
code.haskell.org
thank you, it's all are great news. some questions:
when you plan to make code.haskell.org available?
is its funding will be
In addition, we are in the process of setting up a separate server
called
code.haskell.org
when you plan to make code.haskell.org available?
When it is ready. Wait for further announcements.
is its funding will be reliable? for example, if we don't get money
from Google in 2008
Andrew Coppin wrote:
such that all_trees [1,2,3] will yield
[
Leaf 1,
Leaf 2,
Leaf 3,
Branch (Leaf 1) (Leaf 2),
Branch (Leaf 1) (Leaf 3),
Branch (Leaf 2) (Leaf 1),
Branch (Leaf 2) (Leaf 3),
Branch (Leaf 3) (Leaf 1),
Branch (Leaf 3) (Leaf 2),
Branch (Branch (Leaf 1) (Leaf 2)) (Leaf 3),
Branch
*Andrew Coppin wrote:
*
| I'm trying to construct a function
|
| all_trees :: [Int] - [Tree]
|
| such that all_trees [1,2,3] will yield
:
If you write a helper function that takes an N element list, and returns
all 2^N ways of dividing those elements into 2 lists, e.g.
splits ab --
On Thu, 14 Jun 2007, Tom Pledger wrote:
*Andrew Coppin wrote:
*
| I'm trying to construct a function
|
| all_trees :: [Int] - [Tree]
|
| such that all_trees [1,2,3] will yield
:
If you write a helper function that takes an N element list, and returns
all 2^N ways of dividing
apfelmus wrote:
Explanation and the code:
import Data.List
import Control.Applicative
import qualified Data.Foldable as Foldable
import Data.Traversable as Traversable
import Control.Monad.State
data Tree a = Leaf a | Branch (Tree a) (Tree a) deriving (Show)
Hi
Can you think of a fourth way of redefining disjunct using pattern matching?
vee :: Bool - Bool - Bool
vee _ True = True
vee True _ = True
vee _ _ = False
ve :: Bool - Bool - Bool
ve True True = True
ve True False = True
ve False True = True
ve False False = False
v :: Bool - Bool - Bool
v
PR Stanley [EMAIL PROTECTED] writes:
Hi
Can you think of a fourth way of redefining disjunct using pattern matching?
vee :: Bool - Bool - Bool
vee _ True = True
vee True _ = True
vee _ _ = False
In the same spirit:
f False False = False
f _ _ = True
[mailto:[EMAIL PROTECTED] On Behalf Of PR Stanley
Hi
Can you think of a fourth way of redefining disjunct using
pattern matching?
vee :: Bool - Bool - Bool
vee _ True = True
vee True _ = True
vee _ _ = False
How many ways do you want? I think this is correct, and is only strict
in the
On Wed, Jun 13, 2007 at 02:37:37PM +0100, PR Stanley wrote:
Hi
Can you think of a fourth way of redefining disjunct using pattern matching?
vee :: Bool - Bool - Bool
vee _ True = True
vee True _ = True
vee _ _ = False
ve :: Bool - Bool - Bool
ve True True = True
ve True False = True
ve
Mirko Rahn wrote:
apfelmus wrote:
data Tree a = Leaf a | Branch (Tree a) (Tree a) deriving (Show)
permTrees xs = concat . takeWhile (not . null) . map
(flip evalStateT xs . Traversable.sequence) $ trees select
where
select = StateT $ \xs -
Hi all,
We've had a discussion on #haskell about how we can make a function
that reads in serialized values of an open data type, such as
class (Show a, Read a) = MyClass a where
typeTag :: a - String
... operations on the open data type...
data Obj = forall a. MyClass a = Obj { unObj ::
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA1
Benja Fallenstein wrote:
Hi all,
We've had a discussion on #haskell about how we can make a function
that reads in serialized values of an open data type, such as
[...]
However, this is still kind of boring. Is there a better way? If not,
is its funding will be reliable? for example, if we don't get money
from Google in 2008 year?
in irc some time ago i brought up the topic of something like the
freebsd or wikimedia foundations, but for haskell. if you can give me
a secure and trustworthy method of payment, and as a bonus, a tax
Hi Isaac,
2007/6/13, Isaac Dupree [EMAIL PROTECTED]:
Since Show instances can overlap (e.g. (show (1::Int)) == (show
(1::Integer))), we need to tag with the type.
Indeed. But that's the easy part :-)
Reminds me of Typeable.
Since GHC lets us derive Typeable with a guarantee of different
is its funding will be reliable? for example, if we don't get money
from Google in 2008 year?
in irc some time ago i brought up the topic of something like the
freebsd or wikimedia foundations, but for haskell. if you can give me
a secure and trustworthy method of payment, and as a bonus, a
is its funding will be reliable? for example, if we don't get money from
Google in 2008 year?
Some hosting companies, like http://turtol.com/ offer pay once, keep
forever. Would that be an option?
Thanks,
Greg
___
Haskell-Cafe mailing list
Bryan Burgers wrote:
Similarly, the Perl community has a foundation, and I believe giving
to it is tax-deductible. You could look in to how they do it.
Setting up a 501(c)(3) foundation is a morass of paperwork. If people
within the US are interested in writing tax deductible cheques, a far
Hello Benja,
Wednesday, June 13, 2007, 6:12:25 PM, you wrote:
We've had a discussion on #haskell about how we can make a function
that reads in serialized values of an open data type, such as
look at Data.Generics.Text which may be implements exactly what you
need
--
Best regards,
Bulat
Hi Bulat,
2007/6/13, Bulat Ziganshin [EMAIL PROTECTED]:
We've had a discussion on #haskell about how we can make a function
that reads in serialized values of an open data type, such as
look at Data.Generics.Text which may be implements exactly what you
need
Unfortunately not.
Jon Fairbairn wrote:
I'm trying to construct a function
all_trees :: [Int] - [Tree]
such that all_trees [1,2,3] will yield
[
Leaf 1,
Leaf 2,
Leaf 3,
Branch (Leaf 1) (Leaf 2),
Branch (Leaf 1) (Leaf 3),
Branch (Leaf 2) (Leaf 1),
Branch (Leaf 2) (Leaf 3),
Branch (Leaf 3) (Leaf 1),
Branch (Leaf
Colin DeVilbiss wrote:
On 6/12/07, Andrew Coppin [EMAIL PROTECTED] wrote:
Based on the sample output, I'm guessing that the desired output is
every tree which, when flattened, gives a permutation of a non-empty
subset of the supplied list. This limits the output to trees with up
to n leaves.
Paul Johnson wrote:
Marc A. Ziegert wrote:
http://xkcd.com/c248.html
( join /= coreturn )
IMHO this could be a beautiful and easy way to explain monads.
comments?
I read it as a take on Godel Escher Bach, especially the stuff about
counterfactual situations. But you are right. Actually
ghc-pkg list says a package is installed, but ghci won't load its
module (HDBC-ODBC)
Any advice?
[EMAIL PROTECTED] ~/haskellInstalls/HDBC-odbc-1.0.1.0
$ ghc-pkg list
c:/ghc/ghc-6.6.1\package.conf:
Cabal-1.1.6.2, GLUT-2.1.1, HAppS-0.8.4, HDBC-1.0.1,
HDBC-odbc-1.0.1.0, HUnit-1.1.1,
This doesn't enumerate them in the order you want, but maybe it doesn't
matter.
module Trees where
combinations :: [a] - [[a]]
combinations [] = [[]]
combinations (x:xs)
= combinations xs ++ [ x:xs' | xs' - combinations xs ]
data Tree = Leaf Int | Branch Tree Tree
deriving (Show)
trees
Andrew Coppin [EMAIL PROTECTED] writes:
Jon Fairbairn wrote:
I'm trying to construct a function
all_trees :: [Int] - [Tree]
such that all_trees [1,2,3] will yield
[
Leaf 1,
Leaf 2,
Leaf 3,
Branch (Leaf 1) (Leaf 2),
Branch (Leaf 1) (Leaf 3),
Branch (Leaf 2) (Leaf 1),
On Wed, Jun 13, 2007 at 05:12:25PM +0300, Benja Fallenstein wrote:
However, this is still kind of boring. Is there a better way? If not,
would it be a good idea to have compiler support for building this
kind of type table?
The compiler does build exactly such a table - it's called a symbol
2007/6/14, Stefan O'Rear [EMAIL PROTECTED]:
On Wed, Jun 13, 2007 at 05:12:25PM +0300, Benja Fallenstein wrote:
However, this is still kind of boring. Is there a better way? If not,
would it be a good idea to have compiler support for building this
kind of type table?
The compiler does build
Hi everyone,
As we all know, FiniteMap was deprecated, and with GHC-6.6 Data.Map
must be used instead. Some function names in Data.Map clash with names
in prelude, and Map is usually imported qualified.
Happy generates GLR parsers (-l), but the templates it uses keep calling
FiniteMap
On Thu, Jun 14, 2007 at 12:38:27AM +0200, Iván Pérez Domínguez wrote:
Hi everyone,
As we all know, FiniteMap was deprecated, and with GHC-6.6 Data.Map
must be used instead. Some function names in Data.Map clash with names
in prelude, and Map is usually imported qualified.
Happy
Marc asked:
http://xkcd.com/c248.html
( join /= coreturn )
IMHO this could be a beautiful and easy way to explain monads.
comments?
I'll eat my hat if there isn't a formal way of looking at this. I'm
not qualified to put it together coherently but it goes something like
this: modal logic has
Hi, Henning Thielemann.
Thanks for your help. That is usful.
I have wrote the target function like this, and tested.
mkBlocks (w,h) = map concat . concat . transpose . chop h . map (chop w)
Hi, Dr. Janis Voigtlaender.
This is not a homework, though likely to be one.
I just use Haskell to
I wanted to point out:
http://exitlist.torproject.org/
written in Haskell. I haven't seen any announcements or info on this list
(apologies if someone else mentioned it already). For the record, I'm not
affiliated with the project in any way.
Tim Newsham
newsham:
I wanted to point out:
http://exitlist.torproject.org/
written in Haskell. I haven't seen any announcements or info on this list
(apologies if someone else mentioned it already). For the record, I'm not
affiliated with the project in any way.
Is the source available?
--
I wanted to point out:
http://exitlist.torproject.org/
Is the source available?
Yup. It's all there on the page:
You can download the current revision from the hidden service or from
a local mirror. It's probably wise to check out the current version from
the darcs repository
41 matches
Mail list logo
