Best way for a 3d matrix

Ok, I'll see if I can find some VHDL tutorial.

Just one last help if possible for me to understand why I get this error(i've had this error before).

this following code shouldn't be working?

I get an error: "Error (10476): VHDL error at RCT.vhd(74): type of identifier "entrada" does not agree with its usage as "array_saida" type".

As far as I understand, entrada and saida is the same type of array.

---------PACKAGE---------

LIBRARY ieee;

USE ieee.std_logic_1164.all;

PACKAGE matrizes IS

TYPE array_entrada IS ARRAY (0 TO 3, 0 TO 3) OF STD_LOGIC_VECTOR(3 downto 0);

TYPE array_saida IS ARRAY (0 TO 3, 0 TO 3) OF STD_LOGIC_VECTOR(3 downto 0);

END matrizes;

------------------------------

LIBRARY ieee;

USE ieee.std_logic_1164.all;

USE work.matrizes.all;

ENTITY rct IS

PORT (

clk: IN STD_LOGIC;

entrada: IN array_entrada;

saida: OUT array_saida);

END rct;

ARCHITECTURE comportamento OF rct IS

BEGIN

saida<=entrada;

END comportamento;

Thank You!