apl: Phase 3 reshape ⍴ / transpose ⍉ — 27/27 structural tests green

Add apl-reshape (dyadic ⍴, cycling), apl-transpose (monadic ⍉, reverse axes), apl-transpose-dyadic (dyadic ⍉, permutation), plus helpers apl-strides / apl-flat->multi / apl-multi->flat. lib/apl/tests/structural.sx: 27 new tests covering ravel, reshape, monadic/dyadic transpose across scalar/vector/matrix/3-D cases. test.sh now runs structural.sx via its own inline framework (skips stale tests/runtime.sx which targeted a pre-Phase-2 list-based API). Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
2026-05-06 18:36:43 +00:00
parent 2314735431
commit be26f77410
3 changed files with 289 additions and 4 deletions
--- a/lib/apl/runtime.sx
+++ b/lib/apl/runtime.sx
@@ -347,3 +347,92 @@
          build
          (fn (i acc) (if (< i 1) acc (build (- i 1) (cons i acc)))))
        (apl-vector (build n (list)))))))
+
+(define
+  apl-strides
+  (fn
+    (shape)
+    (map
+      (fn (i) (reduce * 1 (drop shape (+ i 1))))
+      (range 0 (len shape)))))
+
+(define
+  apl-flat->multi
+  (fn
+    (flat shape strides)
+    (map
+      (fn (i) (mod (floor (/ flat (nth strides i))) (nth shape i)))
+      (range 0 (len shape)))))
+
+(define
+  apl-multi->flat
+  (fn (coords strides) (reduce + 0 (map * coords strides))))
+
+(define
+  apl-reshape
+  (fn
+    (shape-arr data-arr)
+    (let
+      ((new-shape (if (scalar? shape-arr) (list (disclose shape-arr)) (get shape-arr :ravel)))
+        (src-ravel
+          (if
+            (scalar? data-arr)
+            (list (disclose data-arr))
+            (get data-arr :ravel))))
+      (let
+        ((new-size (reduce * 1 new-shape)) (src-len (len src-ravel)))
+        (let
+          ((new-ravel (if (= new-size 0) (list) (if (= src-len 0) (map (fn (i) 0) (range 0 new-size)) (map (fn (i) (nth src-ravel (mod i src-len))) (range 0 new-size))))))
+          (make-array new-shape new-ravel))))))
+
+(define
+  apl-transpose
+  (fn
+    (arr)
+    (let
+      ((shape (get arr :shape)) (ravel (get arr :ravel)))
+      (if
+        (< (len shape) 2)
+        arr
+        (let
+          ((new-shape (reverse shape)) (strides (apl-strides shape)))
+          (let
+            ((new-strides (apl-strides new-shape)) (new-size (len ravel)))
+            (make-array
+              new-shape
+              (map
+                (fn
+                  (new-flat)
+                  (let
+                    ((new-coords (apl-flat->multi new-flat new-shape new-strides)))
+                    (nth
+                      ravel
+                      (apl-multi->flat (reverse new-coords) strides))))
+                (range 0 new-size)))))))))
+
+(define
+  apl-transpose-dyadic
+  (fn
+    (perm-arr data-arr)
+    (let
+      ((perm (map (fn (p) (- p apl-io)) (get perm-arr :ravel)))
+        (shape (get data-arr :shape))
+        (ravel (get data-arr :ravel)))
+      (let
+        ((new-shape (map (fn (k) (nth shape k)) perm))
+          (strides (apl-strides shape)))
+        (let
+          ((inv-perm (map (fn (j) (index-of perm j)) (range 0 (len perm))))
+            (new-strides (apl-strides new-shape))
+            (new-size (len ravel)))
+          (make-array
+            new-shape
+            (map
+              (fn
+                (new-flat)
+                (let
+                  ((new-coords (apl-flat->multi new-flat new-shape new-strides)))
+                  (let
+                    ((old-coords (map (fn (i) (nth new-coords (nth inv-perm i))) (range 0 (len shape)))))
+                    (nth ravel (apl-multi->flat old-coords strides)))))
+              (range 0 new-size))))))))