From: Michael Orlitzky <michael@orlitzky.com>
Date: Wed, 14 Sep 2011 13:30:44 +0000 (-0400)
Subject: Add transpose_zx and z_slice3 functions to MRI.
X-Git-Tag: 0.0.1~135
X-Git-Url: http://gitweb.michael.orlitzky.com/?p=spline3.git;a=commitdiff_plain;h=97117af7a6b89e64b84ac0d1a74734dd6ee9fa6c

Add transpose_zx and z_slice3 functions to MRI.
---

diff --git a/src/MRI.hs b/src/MRI.hs
index 2dd6f65..52be3f7 100644
--- a/src/MRI.hs
+++ b/src/MRI.hs
@@ -139,3 +139,22 @@ blue_dbl_data =
 z_slice :: Elt a => Int -> Array DIM3 a -> Array DIM2 a
 z_slice n arr =
   slice arr (Any :. n :. All :. All)
+
+
+transpose_zx :: Elt a => Array DIM3 a -> Array DIM3 a
+transpose_zx arr =
+  traverse arr
+           (\(Z :. zdim :. ydim :. xdim) -> (Z :. xdim :. ydim :. zdim))
+           (\_ -> (\(Z :. z :. y :. x) -> arr ! (Z :. x :. y :. z)))
+
+
+z_slice3 :: Elt a => Int -> Array DIM3 a -> Array DIM3 a
+z_slice3 n arr
+  | n == 0 = transpose_zx $ current R.++ next
+  | n == zdim-1 = transpose_zx $ previous R.++ current
+  | otherwise = transpose_zx $ previous R.++ current R.++ next
+  where
+    (Z :. zdim :. _ :. _) = extent arr
+    previous = transpose_zx $ reshape mri_slice3d (z_slice (n-1) arr)
+    current = transpose_zx $ reshape mri_slice3d (z_slice n arr)
+    next = transpose_zx $ reshape mri_slice3d (z_slice (n+1) arr)