src/overload/matrices.lisp

   1
   2 (in-package :lineal.overload)
   3
   4 (defstruct mtrix
   5   (dimdom 0 :type integer)
   6   (dimcodom 0 :type integer)
   7   (elems nil :type list))
   8
   9 (defun make-mtrix-like (a elems)
  10   (make-mtrix
  11     :dimdom (mtrix-dimdom a)
  12     :dimcodom (mtrix-dimcodom a)
  13     :elems elems))
  14
  15 (defmethod over-transpose ((u tuple))
  16   (make-mtrix
  17     :dimdom (tuple-dim u)
  18     :dimcodom 1
  19     :elems (list (tuple-elems u))))
  20
  21 ; Return the transpose of a given matrix.V
  22 (defmethod over-transpose ((a mtrix))
  23   (make-mtrix
  24     :dimdom (mtrix-dimcodom a)
  25     :dimcodom (mtrix-dimdom a)
  26     :elems (mtrix-transpose (mtrix-elems a))))
  27
  28 (defmethod add2n ((a mtrix) (b mtrix))
  29   (if (and (= (mtrix-dimdom a) (mtrix-dimdom b))
  30            (= (mtrix-dimcodom a) (mtrix-dimcodom b)))
  31     (make-mtrix-like
  32       a (mtrix-addn (mtrix-elems a)
  33                     (mtrix-elems b)))))
  34
  35 (defmethod subtr2n ((a mtrix) (b mtrix))
  36   (if (and (= (mtrix-dimdom a) (mtrix-dimdom b))
  37            (= (mtrix-dimcodom a) (mtrix-dimcodom b)))
  38     (make-mtrix-like
  39       a (mtrix-subtrn (mtrix-elems a)
  40                       (mtrix-elems b)))))
  41
  42 (defmethod mult2n ((a number) (b mtrix))
  43   (make-mtrix-like
  44     b (scalar-mtrix-multn a (mtrix-elems b))))
  45
  46 (defmethod mult2n ((a mtrix) (b number))
  47   (make-mtrix-like
  48     a (scalar-mtrix-multn b (mtrix-elems a))))
  49
  50 (defmethod mult2n ((a mtrix) (b tuple))
  51   (if (= (mtrix-dimdom a) (tuple-dim b))
  52     (make-tuple
  53       :dim (mtrix-dimcodom a) :elems
  54       (mtrix-coltuple-multn
  55         (mtrix-elems a) (tuple-elems b)))
  56     (throw 'over-ex "Bad dimensions for matrix-vector multiplication.")))
  57
  58 (defmethod mult2n ((a tuple) (b mtrix))
  59   (if (= (tuple-dim a) (mtrix-dimcodom b))
  60     (make-tuple
  61       :dim (mtrix-dimdom b) :elems
  62       (car (mtrix-mult2n
  63              (list (tuple-elems a)) (mtrix-elems b))))
  64     (throw 'over-ex "Bad dimensions for vector-matrix multiplication.")))
  65
  66 (defmethod mult2n ((a mtrix) (b mtrix))
  67   (if (= (mtrix-dimdom a) (mtrix-dimcodom b))
  68     (make-mtrix
  69       :dimdom (mtrix-dimdom b)
  70       :dimcodom (mtrix-dimcodom a) :elems
  71       (mtrix-mult2n (mtrix-elems a) (mtrix-elems b)))
  72     (throw 'over-ex "Mismatched dimensions for matrix multiplication.")))
  73
  74 (defmethod divis2n ((a mtrix) (b number))
  75   (make-mtrix-like
  76     a (scalar-mtrix-multn
  77         (/ b) (mtrix-elems a))))
  78