September 2017 Update

Task/Matrix-arithmetic/Forth/matrix-arithmetic.fth

@@ -0,0 +1,38 @@
+S" fsl-util.fs" REQUIRED
+S" fsl/dynmem.seq" REQUIRED
+[UNDEFINED] defines [IF] SYNONYM defines IS [THEN]
+S" fsl/structs.seq" REQUIRED
+S" fsl/lufact.seq" REQUIRED
+S" fsl/dets.seq" REQUIRED
+S" permute.fs" REQUIRED
+
+VARIABLE the-mat
+: add-perm ( p0 p1 p2 ... pn n s -- )
+  DROP  \ sign
+  1E
+  1 DO
+    the-mat @ SWAP 1- I 1- }} F@ F*
+  LOOP
+  DROP  \ Dummy element because we're using 1-based indexing
+  F+ ;
+: permanent ( len mat -- ) ( F: -- perm )
+  the-mat !
+  0E
+  ['] add-perm perms ;
+
+3 SET-PRECISION
+2 2 float matrix m2{{
+1e 2e  3e 4e  2 2 m2{{ }}fput
+lumatrix lmat
+3 3 float matrix m3{{
+2e 9e 4e  7e 5e 3e  6e 1e 8e  3 3 m3{{ }}fput
+
+lmat 2 lu-malloc
+m2{{ lmat lufact
+lmat det F. 2 m2{{ permanent F. CR
+lmat lu-free
+
+lmat 3 lu-malloc
+m3{{ lmat lufact
+lmat det F. 3 m3{{ permanent F. CR
+lmat lu-free