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我正在尝试计算不同大小矩阵的特征值和特征向量。我正在使用一段非常简单的 Fortran90 代码,我正在编译它并链接到英特尔 MKL 包中包含的适当 Lapack 库,该库在我的机器中可用,它在 Ubuntu 中运行。代码“matrix_diag_01.f90”附在消息的末尾。“random”模块只包含来自 Numerical Recipes 的“ran”随机数生成器。代码使用编译良好

ifort -I $(MKLPATH) -o matrix_diag_01 matrix_diag_01.f90 
      random.f90 $(MKLPATH)libmkl_lapack95.a -Wl,--start-group  
      $(MKLPATH)libmkl_intel_lp64.a $(MKLPATH)libmkl_lapack.a 
      $(MKLPATH)libmkl_intel_thread.a $(MKLPATH)libmkl_core.a
       -Wl,--end-group -lguide -lpthread

当给出较小的矩阵时,可执行文件可以很好地工作。但是,对于大小为 3000x3000 的矩阵,它会产生一些奇怪的行为。首先它给出了这个错误

MKL ERROR : Parameter 8 was incorrect on entry to SSYEVD

但是,对 SSYEVD 的调用中只有 3 个参数。其次,它返回特征向量但不返回特征值。我已经通过在另一台内存更大的机器上编译来检查,但结果是一样的。

有人可以帮忙吗?

谢谢!

PROGRAM matrix_diag_01

USE random

IMPLICIT NONE

INTERFACE 
   SUBROUTINE diag(mat,n)
      INTEGER n
      REAL,DIMENSION(n,n) :: mat
   END SUBROUTINE
END INTERFACE 

INTEGER n,i,j,iseed
REAL, DIMENSION(:), ALLOCATABLE  :: w
REAL, DIMENSION(:,:), ALLOCATABLE :: mat

write (*,*) ' Please enter size of matrix'
read (*,*) n
write (*,*) ' Please type seed'
read (*,*) iseed

allocate (mat(n,n))

do i = 1,n
   do j = 1,n
      mat(i,j) = ran(iseed)
   end do
end do

call diag(mat,n)

stop
END
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
SUBROUTINE diag(mat,n)

  USE mkl95_lapack
  USE mkl95_precision

  IMPLICIT NONE

  CHARACTER(len=1) :: jobz = 'V'

  INTEGER n,i

  REAL,DIMENSION(n,n) :: mat
  REAL,DIMENSION(:,:),ALLOCATABLE :: matt,a
  REAL,DIMENSION(:),ALLOCATABLE :: w

  allocate (matt(n,n),a(n,n),w(n))

  matt = mat*transpose(mat)
  a = sqrt(matt)
  open (unit=7,file="matrix.dat",status="unknown")
  do i = 1,n
     write (7,100) a(i,:)
  end do
  close (unit=7)

  call syevd(a,w,jobz)

  open (unit=8,file="eig_val.dat",status="unknown")
  do i = 1,n
     write (8,100) w(i)
  end do
  close (unit=8)

  open (unit=9,file="eig_vec.dat",status="unknown")
  do i = 1,n
     write (9,100) a(i,:)
  end do
  close (unit=9)

  return
 100 format(5000f16.5)
end
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1 回答 1

2

如果您查看您正在调用的函数的来源,它本身会发出以下调用: http: //software.intel.com/sites/products/documentation/hpc/mkl/lapack/mkl_lapack_examples/ssyevd_ex.f.htm

 LWORK = MIN( LWMAX, INT( WORK( 1 ) ) )

 CALL SSYEVD( 'Vectors', 'Upper', N, A, LDA, W, WORK, LWORK,
         $             IWORK, LIWORK, INFO )

估计参数 LWORK 是错误的。

于 2011-07-06T07:58:41.293 回答