matrices.pas

Makefile

BIN = matrix

matrix: matrix.pas
	fpc matrix.pas -o$(BIN)
clean:
	rm *.o $(BIN)

Program solving addition of two matrices.

program matrices;

{**
 * Vaclav Bohac (c) 2011.
 * BSD License.
 *}

type
	matrix = array of array of integer;



{**
 * Prints matrix to std. output.
 * @param  matrix  A
 *}
procedure print_matrix(A : matrix);
var 
	i, j, m, n : integer;
begin
	m := length(A);
	n := length(A[0]);
	
	for i := 0 to m - 1 do
	begin
		for j := 0 to n - 1 do
		begin
			write(A[i, j], ' ')
		end;
		writeln()
	end;
end;


{**
 * Tests if two matrices have the same dimensions.
 * @param  matrix  A
 * @param  matrix  B
 * @return boolean
 *}
function test_eq_type(A, B: matrix) : boolean;
var
	Am, An, Bm, Bn : integer;
begin
	Am := length(A);
	An := length(A[0]);
	Bm := length(B);
	Bn := length(B[0]);

	test_eq_type := (Am = Bm) AND (An = Bn)
end;



{**
 * Adds two equaly sized matrices.
 * @param  matrix  A
 * @param  matrix  B
 * @return integer
 *}
function add_matrices(A, B: matrix) : matrix;
var
	C : matrix;
	i, j, m, n : integer;
begin
	m := length(A);
	n := length(A[0]);
	SetLength(C, m, n);
	
	for i := 0 to m - 1 do
	begin
		for j := 0 to n - 1 do
		begin
			C[i, j] := A[i, j] + B[i, j]
		end
	end;

	add_matrices := C
end;



var
	A, B : matrix;
	i, j, m, n : integer;

begin {* entry point *}
	m := 5;
	n := m;

	setlength(A, m, n);
	setlength(B, m, n);

	for i := 0 to m - 1 do
	begin
		for j := 0 to n - 1 do
		begin
			A[i, j] := i;
			B[i, j] := j
		end
	end;

	if not test_eq_type(A, B) then
		writeln('Types are not equal')
	else begin
		print_matrix(A);
		writeln();
		print_matrix(B);
		writeln();
		print_matrix(add_matrices(A, B))
	end;
end.