数组内的 Fortran 数组

Question

我想获取一个数组，但这个数组包含更多数组。我将在一个例子中描述！我想创建 4 个矩阵。主矩阵是E。

Program array1
!*************************************************! 
implicit none
INTEGER, PARAMETER :: m=2 !rows
INTEGER, PARAMETER :: n=2 !cols
Real, DIMENSION(m,n) :: A,D
Real, DIMENSION(1,2) :: B,C
REAL, allocatable,DIMENSION(:,:) :: E
allocate(E(4,4))
! Assign values to the matrix
A(1,:)=(/ 1,  1 /)   
A(2,:)=(/ 1, 2/)  
B(1,:)=(/ 1, 2/)   
C(1,:)=(/ 1,  1 /)   
D(1,:)=(/ 1,  1 /)   
D(2,:)=(/ 1,  3 /)  
!E=(/A, B
!    C, D)
! This shape of array
!E=[A B
!   C D]
!Result should be as under
!E=[1 1 1 2
!   1 2 0 0
!   1 1 1 1
!   0 0 1 3]
print *,E
End program array1

如何在 Fortran 中获取此数组 (E(？我正在研究 f90 和 f95。我创建了一个新数组，它是数组(E(。重要的是获得 E，我可以在数组后改进，因为我不知道我将在数组中使用哪种情况或函数。如果是 matlab，这很容易，但对于 fotran 我不知道！

Answer 1

尝试使用数组串联操作逐行分配数组[a,b]

Program array1
!*************************************************! 
implicit none
INTEGER, PARAMETER :: m=2 !rows
INTEGER, PARAMETER :: n=2 !cols
Real, DIMENSION(m,n) :: A,D
Real, DIMENSION(m,n) :: B,C              ! made B,C conforming
REAL, allocatable,DIMENSION(:,:) :: E
allocate(E(2*m,2*n))
! Assign values to the matrix
A(1,:)=[ 1, 1 ]   
A(2,:)=[ 1, 2 ]  
B(1,:)=[ 1, 2 ]   
C(1,:)=[ 1, 1 ]   
D(1,:)=[ 1, 1 ]   
D(2,:)=[ 1, 3 ]
! This shape of array
!E=[A B
!   C D]
! assign row-by-row, using array concat
E(1,:) = [A(1,:),B(1,:)]
E(2,:) = [A(2,:),B(2,:)]
E(3,:) = [C(1,:),D(1,:)]
E(4,:) = [C(2,:),D(2,:)]
! print results row-by-row
write (*,*) E(1,:)
write (*,*) E(2,:)
write (*,*) E(3,:)
write (*,*) E(4,:)
End program array1

或者，您可以使用数组部分

E(1:2, 1:2) = A
E(1:1, 3:4) = B
E(3:3, 1:2) = C
E(3:4, 3:4) = D

Answer 2

我写了一个函数，catmat，它获取两个 2D 数组并沿一个公共维度连接它们。请参阅E和F以了解其工作原理。所需的数组是G。

请注意，分配是在catmat中完成的。

program main
implicit none
real, dimension(2,2) :: A
real, dimension(1,2) :: B
real, dimension(1,2) :: C
real, dimension(2,2) :: D
real, dimension(:,:), allocatable :: E
real, dimension(:,:), allocatable :: F
real, dimension(:,:), allocatable :: G
integer :: i
A = reshape( [1, 2, 3, 4], [2,2] )
B(1,:) = [ -1, -2 ]
C(1,:) = [ -3, -4 ]
D = reshape( [5, 6, 7, 8], [2,2] )

write(*,*) ( A(i,:), NEW_LINE('a'), i = 1, size(A,dim=1) )
write(*,*) ( D(i,:), NEW_LINE('a'), i = 1, size(D,dim=1) )

E = catmat( A, D, 1)
write(*,*) "size of E", size(E, dim=1), size(E, dim=2)
write(*,*) ( E(i,:), NEW_LINE('a'), i = 1, size(E,dim=1) )
F = catmat( A, D, 2)
write(*,*) "size of F", size(F, dim=1), size(F, dim=2)
write(*,*) ( F(i,:), NEW_LINE('a'), i = 1, size(F,dim=1) )
G = catmat( catmat( A, B, 1), catmat( C, D, 1), 2)
write(*,*) "size of G", size(G, dim=1), size(G, dim=2)
write(*,*) ( G(i,:), NEW_LINE('a'), i = 1, size(G,dim=1) )

contains
function catmat(matl, matr, cdim) result(res)
real, dimension(:,:), intent(in)  :: matl
real, dimension(:,:), intent(in)  :: matr
integer, intent(in)               :: cdim
real, dimension(:,:), allocatable :: res
integer                           :: max_dim
! Assuming 2d arrays
if( cdim .ne. 1 .and. cdim .ne. 2 ) then
write(*,*) "ERROR"
stop
end if
max_dim =  size(matl,dim=cdim)
if ( size(matr,dim=cdim) .gt. size(matl,dim=cdim) ) max_dim = size(matr,dim=cdim)

if( cdim .eq. 1 ) then
allocate( res( max_dim, size(matl,dim=2) + size(matr,dim=2) ) )
else
allocate( res( size(matl,dim=1) + size(matr,dim=1), max_dim ) )
end if
res = 0
if(cdim .eq.1 ) then
res(:,1:size(matl,dim=2)) = matl
res(:,size(matl,dim=2)+1:size(matl,dim=2)+size(matr,dim=2)) = matr
else
res(1:size(matl,dim=1),:) = matl
res(size(matl,dim=1)+1:size(matl,dim=1)+size(matr,dim=1),:) = matr
end if
end function catmat
end program main