2 files changed, 14 insertions, 0 deletions

diff --git a/lib/Data/Packed/Internal/Matrix.hs b/lib/Data/Packed/Internal/Matrix.hs
index 63ebddf..e76500b 100644
--- a/lib/Data/Packed/Internal/Matrix.hs
+++ b/lib/Data/Packed/Internal/Matrix.hs
@@ -24,6 +24,8 @@ import Complex
 import Control.Monad(when)
 import Data.List(transpose,intersperse)
 import Data.Maybe(fromJust)
+import Foreign.C.String
+import Foreign.C.Types
 
 -----------------------------------------------------------------
 
@@ -371,6 +373,16 @@ fromComplex z = (r,i) where
 comp :: Vector Double -> Vector (Complex Double)
 comp v = toComplex (v,constant 0 (dim v))
 
+-- | loads a matrix efficiently from formatted ASCII text file (the number of rows and columns must be known in advance).
+fromFile :: FilePath -> (Int,Int) -> IO (Matrix Double)
+fromFile filename (r,c) = do
+    charname <- newCString filename
+    res <- createMatrix RowMajor r c
+    c_gslReadMatrix charname // mat dat res // check "gslReadMatrix" []
+    --free charname  -- TO DO: free the auxiliary CString
+    return res
+foreign import ccall "aux.h matrix_fscanf" c_gslReadMatrix:: Ptr CChar -> TM
+
 -------------------------------------------------------------------------
 
 -- Generic definitions
diff --git a/lib/Data/Packed/Internal/aux.h b/lib/Data/Packed/Internal/aux.h
index 83111e5..73334e3 100644
--- a/lib/Data/Packed/Internal/aux.h
+++ b/lib/Data/Packed/Internal/aux.h
@@ -26,3 +26,5 @@ int diagR(KRVEC(d),RMAT(r));
 int diagC(KCVEC(d),CMAT(r));
 
 const char * gsl_strerror (const int gsl_errno);
+
+int matrix_fscanf(char*filename, RMAT(a));