Since I brought this up (search haskell' list) I should probably volunteer to help. If people agree I can coordinate an effort to build a mathematically sound hierarchy. Unfortunately my mathematical knowledge is less than ideal for this purpose (I am actively remedying this at university). However, if there is an administrative burden I volunteer to shoulder it. On a related note I have written a binding to Matlab data files and arrays if anyone is interested, and I am embarking on a project to bind to CBLAS and CLAPack. Vivian

Jacques Carette wrote:

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perhaps i was mistaken in thinking that there is a group of math-interested haskellers out there discussing, developing, and documenting the area? or perhaps that group needs introductory tutorials presenting its work? My guess is that there are a number of people "waiting in

the wings",

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waiting for a critical mass of features to show up before really diving in. See http://www.cas.mcmaster.ca/plmms07/ for my reasons for being both interested and wary).

Probably the simplest test case is the difficulties that people are (still) encountering doing matrix/vector algebra in Haskell. One either quickly encounters efficiency issues (although PArr might help), or typing issues (though many tricks are known, but not necessarily simple). Blitz++ and the STL contributed heavily to C++ being taken seriously by people in the scientific computation community. Haskell has even more _potential_, but it is definitely unrealised potential.

I am one of those mathematicians "waiting in the wings." Haskell looked very appealing at first, and the type system seems perfect, especially for things like multilinear algebra where currying and duality is fundamental. I too was put off by the Num issues though--strange mixture of sophisticated category theory and lack of a sensible hierarchy of algebraic objects.

However, I've decided I'm more interested in helping to fix it than wait; so count me in on an effort to make Haskell more mathematical. For me that probably starts with the semigroup/group/ring setup, and good arbitrary-precision as well as approximate linear algebra support.

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I've been watching this thread for quite a while now, and it seems to me that there is quite a bit of interest in at least working on a new Prelude. I've also noticed a 'The Other Prelude' page on the wiki [http://haskell.org/haskellwiki/The_Other_Prelude] and they seem to have a start on this. So it seems that we should actually start this, because people will contribute. Can somebody with good Cabal skills and maybe access to darcs.haskell.org start a new library for people to start patching?

Bryan Burgers

On Apr 2, 2007, at 3:24 PM, Andrzej Jaworski wrote:

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I too was put off by the Num issues though--strange mixture of sophisticated category theory and lack of a sensible hierarchy of algebraic objects.

Perhaps we should replace CT with lattice theoretic thinking (e.g. functor = monotonic function) before cleaning up the type-related mess? See: http://citeseer.ist.psu.edu/269479.html

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so count me in on an effort to make Haskell more mathematical. For me that probably starts with the semigroup/group/ring setup, and good arbitrary-precision as well as approximate linear algebra support.

I agree: semigoups like lattices are everywhere. Then there could be a uniform treatment of linear algebra, polynomial equations, operator algebra, etc. So, perhaps haste is not a good advice here?

-Andrzej