[Haskell-cafe] BLAS Solve Example

[Alberto Ruiz]

Darrin Thompson wrote:
> I'm stuck on something that I thought would be easy.
> 
> I have a matrix and a vector.
> 
>> module Main where
>> import Data.Vector.Dense
>> import Data.Matrix.Dense
>> import BLAS.Matrix.Solve
>>
>> m = listMatrix (2, 3) ([1, 2, 3, 4, 5, 6]::[Double])
>> v = listVector 2 ([1, 2]::[Double])
>>
>> main = do ???
> 
> Can I use one of the haskell libraries to solve that system? My goal
> is to automate some tedium on small exercises from the Linear Algebra
> text by Jim Heffron.
> 
> --
> Darrin

Using hmatrix:

 > import Numeric.LinearAlgebra
 >
 > m = (2><3) [1, 2, 3,
 >             4, 5, 6]
 >
 > v = 2 |> [1, 2 :: Double]
 >
 > sol = m <\> v

$ ghci solve.hs
*Main> sol
3 |> [-5.555555555555511e-2,0.11111111111111113,0.2777777777777776]

Best regards,

Alberto