What is the situation regarding statically dimension-checked linear algebra libraries? It seems that Frederik Eaton was working on one in 2006 (see the paper "Statically typed linear algebra in Haskell"), and he produced the Vectro library from this, based on GSLHaskell.

Are there any more recent efforts into this, particularly using the new TFs? If not, I might have a go at it, as a thin wrapper for hmatrix.

The BLAS bindings I wrote use phantom types to make sure the dimensions are consistent. See, for example the functions to get row and column views of a matrix: http://hackage.haskell.org/packages/archive/blas/0.6/doc/html/Data-Matrix-De... Also, the multiplication routines: http://hackage.haskell.org/packages/archive/blas/0.6/doc/html/BLAS-Matrix-Im... I've found that phantom types are a good trade off: they provide enough type safety to catch common mistakes without being too much of a hassle to use. Another benefit (which I didn't anticipate) is that they help a *lot* with documentation. I'm skeptical of value that comes from stronger typing. At some point the types become too much of a hassle to be worth using. Even phantom types get in the way sometimes and require use of either GADTs, unsafeCoerce, or both, which is annoying. I'd be interested to hear about any developments you make in this area. Patrick p.s. If you're interested in trying it out, the version of blas on hackage doesn't compile with ghc-6.10.1, but the version in the darcs repository at http://stat.stanford.edu/~patperry/code/blas does.