Question

我正在努力学习LAPACK的dgetrf和dgetri例程。下面是我创建的子程序（变量fit_coeffs是外部定义的并且是可分配的，这不是问题）。当我运行时，我得到内存分配错误，当我分配fit_coeffs时，由于matmul（ATA，AT）线而出现错误。我通过插入一堆打印语句来了解这一点。此外，打印调用LAPACK子例程后的两个错误检查语句都表示错误。有谁知道这是从哪里来的？我正在使用命令进行编译：

gfortran -Wall -cpp -std=f2003 -ffree-form -L/home/binningtont/lapack-3.4.0/ read_grib.f -llapack -lrefblas。

提前致谢！

subroutine polynomial_fit(x_array, y_array, D)
    integer, intent(in) :: D
    real, intent(in), dimension(:) :: x_array, y_array
    real, allocatable, dimension(:,:) :: A, AT, ATA
    real, allocatable, dimension(:) :: work
    integer, dimension(:), allocatable :: pivot
    integer :: l, m, n, lda, lwork, ok

    l = D + 1
    lda = l
    lwork = l

    allocate(fit_coeffs(l))
    allocate(pivot(l))
    allocate(work(l))
    allocate(A(size(x_array),l))
    allocate(AT(l,size(x_array)))
    allocate(ATA(l,l))

    do m = 1,size(x_array),1
      do n = 1,l,1
        A(m,n) = x_array(m)**(n-1)
      end do
    end do

    AT = transpose(A)
    ATA = matmul(AT,A)

    call dgetrf(l, l, ATA, lda, pivot, ok)
    ! ATA is now represented as PLU (permutation, lower, upper)
    if (ok /= 0) then
      write(6,*) "HERE"
    end if
    call dgetri(l, ATA, lda, pivot, work, lwork, ok)
    ! ATA now contains the inverse of the matrix ATA
    if (ok /= 0) then
      write(6,*) "HERE"
    end if

    fit_coeffs = matmul(matmul(ATA,AT),y_array)

    deallocate(pivot)
    deallocate(fit_coeffs)
    deallocate(work)
    deallocate(A)
    deallocate(AT)
    deallocate(ATA)
  end subroutine polynomial_fit

Answer 1

1）fit_coeffs在哪里宣布？我看不出上面的内容如何编译 1b）隐含无是你的朋友！

2）你在调用点的范围内有一个接口，不是吗？

3）当你有单身时，dgertf和dgetri想要“双精度”。所以你需要sgetrf和sgetri

“修复”所有这些并完成我得到的程序

Program testit

  Implicit None

  Real, Dimension( 1:100 ) :: x, y

  Integer :: D

  Interface 
     subroutine polynomial_fit(x_array, y_array, D)
       Implicit None ! Always use this!!
       integer, intent(in) :: D
       real, intent(in), dimension(:) :: x_array, y_array
     End subroutine polynomial_fit
  End Interface

  Call Random_number( x )
  Call Random_number( y )

  D = 6

  Call polynomial_fit( x, y, D )

End Program testit

subroutine polynomial_fit(x_array, y_array, D)

  Implicit None ! Always use this!!

    integer, intent(in) :: D
    real, intent(in), dimension(:) :: x_array, y_array
    real, allocatable, dimension(:,:) :: A, AT, ATA
    real, allocatable, dimension(:) :: work, fit_coeffs
    integer, dimension(:), allocatable :: pivot
    integer :: l, m, n, lda, lwork, ok

    l = D + 1
    lda = l
    lwork = l

    allocate(fit_coeffs(l))
    allocate(pivot(l))
    allocate(work(l))
    allocate(A(size(x_array),l))
    allocate(AT(l,size(x_array)))
    allocate(ATA(l,l))

    do m = 1,size(x_array),1
      do n = 1,l,1
        A(m,n) = x_array(m)**(n-1)
      end do
    end do

    AT = transpose(A)
    ATA = matmul(AT,A)

    call sgetrf(l, l, ATA, lda, pivot, ok)
    ! ATA is now represented as PLU (permutation, lower, upper)
    if (ok /= 0) then
      write(6,*) "HERE"
    end if
    call sgetri(l, ATA, lda, pivot, work, lwork, ok)
    ! ATA now contains the inverse of the matrix ATA
    if (ok /= 0) then
      write(6,*) "HERE"
    end if

    fit_coeffs = matmul(matmul(ATA,AT),y_array)

    deallocate(pivot)
    deallocate(fit_coeffs)
    deallocate(work)
    deallocate(A)
    deallocate(AT)
    deallocate(ATA)
  end subroutine polynomial_fit

这将完成。如果我省略界面，我会打印“HERE”两次。如果我使用d版本，我会遇到seg错误。

这会回答你的问题吗？

Fortran2003中使用LAPACK的动态内存分配错误

1 个答案: