2.8 N-dimensionnal arrays

N-dimensionnal array can be defined and handled in simple way:

-->M(2,2,2)=3
 M  =
 
(:,:,1)
 
!   0.    0. !
!   0.    0. !
(:,:,2)
 
!   0.    0. !
!   0.    3. !
 
-->M(:,:,1)=rand(2,2)
 M  =
 
(:,:,1)
 
!   0.9329616    0.312642  !
!   0.2146008    0.3616361 !
(:,:,2)
 
!   0.    0. !
!   0.    3. !
 
-->M(2,2,:)
 ans  =
 
(:,:,1)
 
    0.3616361  
(:,:,2)
 
    3.  
-->size(M)
 ans  =
 
!   2.    2.    2. !
 
-->size(M,3)
 ans  =
 
    2.

They can be created from a vector of data and a vector of dimension

-->hypermat([2 3,2],1:12)
 ans  =
 
(:,:,1)
 
!   1.    3.    5. !
!   2.    4.    6. !
(:,:,2)
 
!   7.    9.     11. !
!   8.    10.    12. !

N-dimensionnal matrices are coded as mlists with 2 fields :

-->M=hypermat([2 3,2],1:12);
-->M.dims
 ans  =
 
!   2.    3.    2. !
-->M.entries
 ans  =
 
!   1.  !
!   2.  !
!   3.  !
!   4.  !
!   5.  !
!   6.  !
!   7.  !
!   8.  !
!   9.  !
!   10. !
!   11. !
!   12. !