DEFINITION MODULE MatrixOperations;

(* Matrix operations using dynamic memory *)

(* V1.1, J. Andrea, Jun.22/93 -add Duplicate *)
(* V1.0, J. Andrea, Mar.16/92 *)
(* This code may be freely used and distributed, it may not be sold. *)

(*
* For those operations which return a status in the boolean 'ok',
* the value of 'ok' should be checked before attempting to use the
* resultant matrix.
* If 'ok' is FALSE, then the resultant matrix will not exist.
*)

EXPORT QUALIFIED Matrix,                           (* the type *)
                 Build, Destroy,                   (* matrix creation/deletion*)
                 Put, Get,                         (* element access *)
                 Size, Min, Max, Compare,          (* status *)
                 Ident, Assign,                    (* modify all elements *)
                 Copy, Duplicate,                  (* new copy *)
                 Scale, Add, Multiply,             (* basic operations *)
                 Transpose, Invert, Determinant;   (* advanced operations *)

TYPE Matrix;   (* opaque *)

PROCEDURE Build( VAR a :Matrix; rows, columns :CARDINAL );
(* create a matrix of the specified size *)

PROCEDURE Destroy( VAR a :Matrix );
(* get rid for the specified matrix *)

PROCEDURE Put( a :Matrix; row, col :CARDINAL; value :REAL );
(* put the specified value into the matrix at 'row,col' *)

PROCEDURE Get( a :Matrix; row, col :CARDINAL ) :REAL;
(* return the value at 'row,col' *)

PROCEDURE Size( a :Matrix; VAR rows, cols :CARDINAL );
(* return the size of a matrix *)

PROCEDURE Min( a :Matrix ) :REAL;
(* return the minimum value in the matrix *)

PROCEDURE Max( a :Matrix ) :REAL;
(* return the maximum value in the matrix *)

PROCEDURE Compare( a, b :Matrix ) :BOOLEAN;
(* compare two matricies, return TRUE if they are the same *)

PROCEDURE Ident( a :Matrix );
(* set the matrix to the identity matrix *)

PROCEDURE Assign( a :Matrix; x :REAL );
(* set all elements in the matrix to 'x' *)

PROCEDURE Copy( a, b :Matrix );
(* copy 'a' into 'b', iff sizes are the same *)

PROCEDURE Duplicate( a :Matrix; VAR b :Matrix );
(* copy 'a' into a new 'b' *)

PROCEDURE Scale( a :Matrix; scale :REAL );
(* multiply all elements of matrix 'a' by the scalar 'scale' *)

PROCEDURE Add( a, b :Matrix; VAR c :Matrix; VAR ok :BOOLEAN );
(* add matrix 'a' to 'b', and return 'ok' as TRUE if done *)

PROCEDURE Multiply( a, b :Matrix; VAR c :Matrix; VAR ok :BOOLEAN );
(* multiply matrix 'a' by 'b', and return 'ok' as TRUE if done *)

PROCEDURE Transpose( a :Matrix; VAR b :Matrix );
(* transpose matrix 'a' into a new matrix 'b' *)

PROCEDURE Invert( a :Matrix; VAR b :Matrix; VAR ok :BOOLEAN );
(* invert matrix 'a' into a new matrix 'b', and return 'ok' as TRUE if done *)

PROCEDURE Determinant( a :Matrix; VAR d :REAL; VAR ok :BOOLEAN );
(* return the determinant of 'a' in the value 'd' *)

END MatrixOperations.