function $[$B$,$ C$,$ D$]=$ matrixFun$($A$)$

$\%$ Create a new matrix B that consists of the first and last rows of A

B $=$ A$([1,$ end$],$ :$)$;

$\%$ Create a new matrix C that consists of the elements at the four corners of A

C $=$ A$([1,1,$ end, end$],[1,$ end$])$;

$\%$ Create a new matrix D that consists of the second through last columns

$\%$ in the second through last rows of A

D $=$ A$(2$:end$-1,2$:end$-1)$;

end