;;; Lisplab, level1-array.lisp
;;; Lisp array methods.

;;; Copyright (C) 2009 Joern Inge Vestgaarden
;;;
;;; This program 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 of the License, or
;;; (at your option) any later version.
;;;
;;; This program is distributed in the hope that it will be useful,
;;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
;;; GNU General Public License for more details.
;;;
;;; You should have received a copy of the GNU General Public License along
;;; with this program; if not, write to the Free Software Foundation, Inc.,
;;; 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

(in-package :lisplab)

(defmethod matrix-p ((a array))
  "True for an array of rank 2"
  (= (rank a) 2))

(defmethod vector? ((a array))
  "True for any array through row-major-aref"
  t)

(defmethod dim ((a array) &optional axis)
  (if axis
      (array-dimension a axis)
      (array-dimensions a)))

(defmethod size ((a array))
  (reduce #'* (dim a)))

(defmethod rank ((a array))
  (array-rank a))

(defmethod rows ((a array))
  (array-dimension a 0))

(defmethod cols ((a array))
  (array-dimension a 1))

(defmethod element-type ((a array))
  "Gets the element type of the array"
  (array-element-type a))

(defmethod mref ((a array) row col)
  "Row major order"
  (aref a row col))

(defmethod (setf mref) (value (a array) row col)
  (setf (aref a row col) (convert value (element-type a)))) 

(defmethod vref ((a array) idx)
  "Row major order"
  (row-major-aref a idx))

(defmethod (setf vref) (value (a array) idx)
  (setf (row-major-aref a idx) value)) 

(defmethod make-matrix-instance ((x (eql 'array)) dim value)
  (make-array dim :initial-element value))

(defmethod copy ((a array))
  ;; TODO move to level2 
  (if (vectorp a)
      (copy-seq a)
      (let ((y (make-array (dim a) :element-type (element-type a))))
	(dotimes (i (size a))
	  (setf (row-major-aref y i)
		(row-major-aref a i)))
	y)))