Re: Haskell Matrix Library...

On Tue, 14 Jun 2005, Bulat Ziganshin wrote:

Hello Keean,

Tuesday, June 14, 2005, 3:54:08 PM, you wrote:

KS> class Functor m where KS> fmap :: a -> b -> m a -> m b

KS> But the type of "mmap" is

KS> mmap :: e -> e -> Matrix a i e -> Matrix a i e

KS> in other words we map values to the same type, not a different type.

mmap should be

mmap :: (e -> e1) -> Matrix a i e -> Matrix a i e1

for example, we can map matrix of strings to matrix of its lengths

... or a real valued matrix to a complex valued one.