-------------------------------------------------------------------------------
-- Title      : Matrix Math package for type REAL
-- Project    : 
-------------------------------------------------------------------------------
-- File       : real_matrix_pkg.vhdl
-- Author     : David Bishop  <dbishop@vhdl.org>
-- Company    : 
-- Created    : 2010-04-15
-- Last update: 2010-04-26
-- Platform   : 
-- Standard   : VHDL'93
-------------------------------------------------------------------------------
-- Description: Matrix math package for type REAL
-------------------------------------------------------------------------------
-- Copyright (c) 2010 
-------------------------------------------------------------------------------
-- Revisions  :
-- Date        Version  Author  Description
-- 2010-04-15  1.0      l435385 Created
-------------------------------------------------------------------------------

--

package real_matrix_pkg is

  -- Define arrays of vectors
  -- %%% "real_vector" is defined in VHDL-2008
  type real_vector is array (NATURAL range <>) of REAL;  -- array
  type real_matrix is array (NATURAL range <>, NATURAL range <>) of REAL;  -- real matrix

  -- purpose: matrix multiply
  function "*" (
    l, r : real_matrix)
    return real_matrix;

  -- purpose: matrix by vector
  function "*" (
    l : real_matrix;
    r : real_vector)
    return real_vector;

  -- purpose: multiply a vector by a matrix
  function "*" (
    l : real_vector;
    r : real_matrix)
    return real_vector;

  -- purpose: Multiply a vector by a vector to get a matrix
  function "*" (
    l, r : real_vector)
    return real_matrix;

  -- purpose: multiply a scalar by a matrix
  function "*" (
    l : REAL;
    r : real_matrix)
    return real_matrix;

  -- purpose: multiply a scalar by a matrix
  function "*" (
    l : real_matrix;
    r : REAL)
    return real_matrix;

  -- purpose: matrix addition
  function "+" (
    l, r : real_matrix)
    return real_matrix;

  -- purpose: matrix subtraction
  function "-" (
    l, r : real_matrix)
    return real_matrix;

  -- purpose: Transpose a matrix
  function transpose (
    arg : real_matrix)
    return real_matrix;

  -- purpose: returns a matrix of zeors
  function zeros (
    rows, columns : POSITIVE)
    return real_matrix;

  -- purpose: returns a matrix of zeors
  function ones (
    rows, columns : POSITIVE)
    return real_matrix;

  -- purpose: Returns an identity matrix
  function identity (
    rows, columns : POSITIVE)
    return real_matrix;

  -- purpose: submatrix returns a matrix with 1 less row and column
  -- Used by determinant function
  function submatrix (
    constant row, column : INTEGER;     -- row and column to exclude
    arg                  : real_matrix)
    return real_matrix;

  -- purpose: Finds the determinant of a matrix
  function determinant (
    arg : real_matrix)
    return REAL;

  -- purpose: Inverts a matrix
  function invert (
    arg : real_matrix)
    return real_matrix;

  -- purpose: Prints out a matrix
  procedure print_matrix (
    arg   : in real_matrix;
    index : in BOOLEAN := false);

  -- purpose: Prints out a vector
  procedure print_vector (
    arg   : in real_vector;
    index : in BOOLEAN := false);

  -- purpose: returns true if 2 matricies are equal
--  function "=" (
--    l, r : real_matrix)
--    return BOOLEAN;

--  -- purpose: returns true if 2 matricies are not equal
--  function "/=" (
--    l, r : real_matrix)
--    return BOOLEAN;

  -- Matlab .* operator
  function times (
    l, r : real_matrix)
    return real_matrix;

  -- Matlab ./ operator
  function rdivide (
    l, r : real_matrix)
    return real_matrix;

  
end package real_matrix_pkg;