X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/8cf06c7f74ccb33646dabf1553c4fdbbe030ae6a..d02fe47dd3be7310d1bfd6e802d1fac2ea5f5e9d:/lisp/calc/calc-vec.el

diff --git a/lisp/calc/calc-vec.el b/lisp/calc/calc-vec.el
index e85d1259b5..c079e8985e 100644
--- a/lisp/calc/calc-vec.el
+++ b/lisp/calc/calc-vec.el
@@ -1,7 +1,7 @@
 ;;; calc-vec.el --- vector functions for Calc
 
 ;; Copyright (C) 1990, 1991, 1992, 1993, 2001, 2002, 2003, 2004,
-;;   2005, 2006, 2007 Free Software Foundation, Inc.
+;;   2005, 2006, 2007, 2008 Free Software Foundation, Inc.
 
 ;; Author: David Gillespie <daveg@synaptics.com>
 ;; Maintainer: Jay Belanger <jay.p.belanger@gmail.com>
@@ -10,7 +10,7 @@
 
 ;; GNU Emacs is free software; you can redistribute it and/or modify
 ;; it under the terms of the GNU General Public License as published by
-;; the Free Software Foundation; either version 2, or (at your option)
+;; the Free Software Foundation; either version 3, or (at your option)
 ;; any later version.
 
 ;; GNU Emacs is distributed in the hope that it will be useful,
@@ -32,6 +32,10 @@
 (require 'calc-ext)
 (require 'calc-macs)
 
+;; Declare functions which are defined elsewhere.
+(declare-function math-read-expr-level "calc-aent" (exp-prec &optional exp-term))
+
+
 (defun calc-display-strings (n)
   (interactive "P")
   (calc-wrapper
@@ -475,6 +479,11 @@
   (calc-wrapper
    (calc-binary-op "cros" 'calcFunc-cross arg)))
 
+(defun calc-kron (arg)
+  (interactive "P")
+  (calc-wrapper
+   (calc-binary-op "kron" 'calcFunc-kron arg)))
+
 (defun calc-remove-duplicates (arg)
   (interactive "P")
   (calc-wrapper
@@ -1462,6 +1471,41 @@
     (math-reject-arg a "*Three-vector expected")))
 
 
+;;; Compute a Kronecker product
+(defun calcFunc-kron (x y &optional nocheck)
+  "The Kronecker product of objects X and Y.
+The objects X and Y may be scalars, vectors or matrices.
+The type of the result depends on the types of the operands;
+the product of two scalars is a scalar,
+of one scalar and a vector is a vector,
+of two vectors is a vector.
+of one vector and a matrix is a matrix,
+of two matrices is a matrix."
+  (unless nocheck
+    (cond ((or (math-matrixp x)
+               (math-matrixp y))
+           (unless (math-matrixp x)
+             (setq x (if (math-vectorp x)
+                         (list 'vec x)
+                       (list 'vec (list 'vec x)))))
+           (unless (math-matrixp y)
+             (setq y (if (math-vectorp y)
+                         (list 'vec y)
+                       (list 'vec (list 'vec y))))))
+          ((or (math-vectorp x)
+               (math-vectorp y))
+           (unless (math-vectorp x)
+             (setq x (list 'vec x)))
+           (unless (math-vectorp y)
+             (setq y (list 'vec y))))))
+  (if (math-vectorp x)
+      (let (ret)
+        (dolist (v (cdr x))
+          (dolist (w (cdr y))
+            (setq ret (cons (calcFunc-kron v w t) ret))))
+        (cons 'vec (nreverse ret)))
+    (math-mul x y)))
+
 
 ;; The variable math-rb-close is local to math-read-brackets, but
 ;; is used by math-read-vector, which is called (directly and
@@ -1593,5 +1637,5 @@
 
 (provide 'calc-vec)
 
-;;; arch-tag: 7902a7af-ec69-440a-8635-ebb4db263402
+;; arch-tag: 7902a7af-ec69-440a-8635-ebb4db263402
 ;;; calc-vec.el ends here