Update.

[pytorch.git] / eingather.py

diff --git a/eingather.py b/eingather.py
index f8b3e89..734edbe 100755 (executable)
--- a/eingather.py
+++ b/eingather.py
@@ -15,52 +15,42 @@ def eingather(op, src, *indexes):
     s_indexes = re.findall("\(([^)]*)\)", s_src)
     s_src = re.sub("\([^)]*\)", "_", s_src)
 
-    shape = tuple(src.size(s_src.index(v)) for v in s_dst)
-
-    idx = []
-    n_index = 0
-
-    for i in range(src.dim()):
-        v = s_src[i]
-        if v == "_":
-            index, s_index = indexes[n_index], s_indexes[n_index]
-            n_index += 1
-
-            sub_idx = []
-
-            for i in range(index.dim()):
-                v = s_index[i]
+    all_sizes = tuple(d for s in (src,) + indexes for d in s.size())
+    s_all = "".join([s_src] + s_indexes)
+    shape = tuple(all_sizes[s_all.index(v)] for v in s_dst)
+
+    def do(x, s_x):
+        idx = []
+        n_index = 0
+
+        for i in range(x.dim()):
+            v = s_x[i]
+            if v == "_":
+                idx.append(do(indexes[n_index], s_indexes[n_index]))
+                n_index += 1
+            else:
                 j = s_dst.index(v)
                 a = (
-                    torch.arange(index.size(i))
+                    torch.arange(x.size(i))
                     .reshape((1,) * j + (-1,) + (1,) * (len(s_dst) - j - 1))
                     .expand(shape)
                 )
-                sub_idx.append(a)
+                idx.append(a)
 
-            index = index[sub_idx]
-            idx.append(index)
-        else:
-            j = s_dst.index(v)
-            a = (
-                torch.arange(src.size(i))
-                .reshape((1,) * j + (-1,) + (1,) * (len(s_dst) - j - 1))
-                .expand(shape)
-            )
-            idx.append(a)
+        return x[idx]
 
-    return src[idx]
+    return do(src, s_src)
 
 
 #######################
 
-src = torch.rand(3, 5, 7, 11, 13)
-index1 = torch.randint(src.size(2), (src.size(4), src.size(1), src.size(4)))
+src = torch.rand(3, 5, 7, 11)
+index1 = torch.randint(src.size(2), (src.size(3), src.size(1), src.size(3)))
 index2 = torch.randint(src.size(3), (src.size(1),))
 
-# I want result[a, c, e] = src[c, a, index1[e, a, e], index2[a], e]
+# result[a, c, e] = src[c, a, index1[e, a, e], index2[a]]
 
-result = eingather("ca(eae)(a)e -> ace", src, index1, index2)
+result = eingather("ca(eae)(a) -> ace", src, index1, index2)
 
 # Check
 
@@ -69,6 +59,6 @@ error = 0
 for a in range(result.size(0)):
     for c in range(result.size(1)):
         for e in range(result.size(2)):
-            error += (result[a, c, e] - src[c, a, index1[e, a, e], index2[a], e]).abs()
+            error += (result[a, c, e] - src[c, a, index1[e, a, e], index2[a]]).abs()
 
 print(error.item())