求问fortran大神：This name does not have a type, and must have an explicit type.怎么解决。

Posted 2023-03-20

源代码为：显示第五行（ real(8) in1(n,n), S1(n,n)）出错
subroutine svd(in1,S1,U,VT,n)

implicit none
external DGESVD
character JOBU, JOBVT
real(8) in1(n,n), S1(n,n)
INTEGER INFO, LDA, LDU, LDVT, LWORK, M, N,i
DOUBLE PRECISION A( n,n ), S( n ), U( n, n ),VT( n, n ), WORK(5*n)
LWORK=5*N
A=in1
JOBU ='A'
JOBVT='A'
call DGESVD( JOBU, JOBVT, N, N, A, N, S, U, N, VT, N,WORK, LWORK, INFO )

do i=1,n
S1(i,i)=S(i)
enddo
end subroutine svd

是你的n未定义，你得先定义n才能定义in1(n,n),不然fortran不知道n是多少 参考技术A