2 files changed, 23 insertions, 0 deletions

diff --git a/lib/Numeric/LinearAlgebra/Instances.hs b/lib/Numeric/LinearAlgebra/Instances.hs
index c8bf126..8e11d78 100644
--- a/lib/Numeric/LinearAlgebra/Instances.hs
+++ b/lib/Numeric/LinearAlgebra/Instances.hs
@@ -48,6 +48,24 @@ instance (Show a, Storable a) => (Show (Vector a)) where
 
 ------------------------------------------------------------------
 
+instance (Element a, Read a) => Read (Matrix a) where
+    readsPrec _ s = [((rows><cols) . read $ listnums, rest)]
+        where (thing,rest) = breakAt ']' s
+              (dims,listnums) = breakAt ')' thing
+              cols = read . init . fst. breakAt ')' . snd . breakAt '<' $ dims
+              rows = read . snd . breakAt '(' .init . fst . breakAt '>' $ dims
+
+instance (Element a, Read a) => Read (Vector a) where
+    readsPrec _ s = [((d |>) . read $ listnums, rest)]
+        where (thing,rest) = breakAt ']' s
+              (dims,listnums) = breakAt '>' thing
+              d = read . init . fst . breakAt '|' $ dims
+
+breakAt c l = (a++[c],tail b) where
+    (a,b) = break (==c) l
+
+------------------------------------------------------------------
+
 adaptScalar f1 f2 f3 x y
     | dim x == 1 = f1   (x@>0) y
     | dim y == 1 = f3 x (y@>0)
diff --git a/lib/Numeric/LinearAlgebra/Tests.hs b/lib/Numeric/LinearAlgebra/Tests.hs
index 31ba2ff..7b28075 100644
--- a/lib/Numeric/LinearAlgebra/Tests.hs
+++ b/lib/Numeric/LinearAlgebra/Tests.hs
@@ -174,6 +174,11 @@ runTests n = do
     test (\u -> sin u ** 2 + cos u ** 2 |~| (1::RM))
     test (\u -> cos u * tan u |~| sin (u::RM))
     test (\u -> (cos u * tan u) |~| sin (u::CM))
+    putStrLn "------ read . show"
+    test (\m -> (m::RM) == read (show m))
+    test (\m -> (m::CM) == read (show m))
+    test (\m -> toRows (m::RM) == read (show (toRows m)))
+    test (\m -> toRows (m::CM) == read (show (toRows m)))
     putStrLn "------ some unit tests"
     runTestTT $ TestList
         [ utest "1E5 rots" rotTest