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A error when using "CGEEV" to diagonalize a complex n*n matrix

YiqunLiu
Beginner
‎05-12-2023 01:31 AM
1,742 Views

YiqunLiu_0-1683879101486.png

I just want to diagonalize this matrix (2, 1+i \\  -1+i, -2 ) for my test. Then a error occurs:

"Intel MKL ERROR: Parameter 12 was incorrect on entry to CGEEV".

I need some help for my programming, here's my procedure, maybe something wrong in it. I got my procedure by copying the CGEEV example in "Intel® oneAPI Math Kernel Library
LAPACK Examples”, which appears in page 431-433.

program main
use lapack95
!use blas95
!implicit real(kind=8)(a-h,o-z)
INTEGER INFO,LWORK,N
PARAMETER (LWMAX=1000)
PARAMETER ( N=2 )
PARAMETER ( LDA=N, LDVL=N, LDVR=N )
complex(kind=8) rk(N,N), A(N,N)
complex(kind=8) W(N), VL(LDVL,N), VR(LDVR,N), WORK(LWMAX)
real(kind=8) RWORK(2*N)

EXTERNAL CGEEV

rk(1,1)=2.d0
rk(2,2)=-2.d0
rk(1,2)=CMPLX(1.d0,1.d0)
rk(2,1)=-CMPLX(1.d0,-1.d0)
!=====================================================================
A=rk
write(*,*)"A="
write(*,*)A
LWORK=-1
CALL CGEEV( 'V', 'V', N, A, LDA, W, VL, LDVL, VR, LDVR, WORK, LWORK, RWORK, INFO )

LWORK = MIN( LWMAX, INT( WORK(1) ) )
call cgeev('V', 'V', N, A, LDA, W, VL, LDVL, VR, LDVR, WORK, LWORK, RWORK, INFO )
!======================================================================
write(*,*)
write(*,*)"The eigenvalues and some OUTPUT infomations"
write(*,*)w,info,LWMAX,WORk(1),INT( WORK(1) )
pause

stop
end

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jdelia
New Contributor I
‎05-12-2023 04:13 AM
1,706 Views

Dear YiqunLiu 

Here is a slightly modified version (i) due to problems between real(4) vs real(8) in the use of cmplx ; (ii) and to also compile alternatively with gfortran+atlas:

program main
  !use lapack95
  !use blas95
  !implicit real (kind=8)(a-h,o-z)
  implicit none
  integer :: info, lwork, n
  integer :: lwmax, lda, ldvl, ldvr
  parameter (lwmax=1000)
  parameter (n=2)
  parameter (lda=n, ldvl=n, ldvr=n)
  complex (kind=8) :: rk (n,n), aa (n,n)
  complex (kind=8) :: ww (n), vl (ldvl,n), vr (ldvr,n), work (lwmax)
  real (kind=8) :: rwork (2*n)
  external zgeev
  !
  rk(1,1)= 2.0d0
  rk(2,2)=-2.0d0
  rk(1,2)= cmplx (1.0d0, 1.0d0,kind=8)
  rk(2,1)=-cmplx (1.0d0,-1.0d0,kind=8)
  !
  aa=rk
  lwork=-1
  !
  write (*,*)"aa="
  write (*,*) aa
  call zgeev ('v','v',n,aa,lda,ww,vl,ldvl,vr,ldvr,work,lwork,rwork,info)
  lwork = min (lwmax, int (work(1)))
  call zgeev ('v','v',n,aa,lda,ww,vl,ldvl,vr,ldvr,work,lwork,rwork,info)
  !
  write (*,*)"the eigenvalues and some output infomations"
  write (*,*) ww, info, lwmax, work(1), int(work(1))
  !
end program main

 

Then, (i) with ifort

$ ifort --version

ifort (IFORT) 2021.9.0 20230302
Copyright (C) 1985-2023 Intel Corporation. All rights reserved.

ifort -O2 -o test182-i.exe -L${MKLROOT}/lib/intel64 -lmkl_intel_lp64 -lmkl_intel_thread -lmkl_core -liomp5 -lpthread -ldl test182.f90

$ test182-i.exe
aa=
(2.00000000000000,0.000000000000000E+000) (-1.00000000000000,1.00000000000000)
(1.00000000000000,1.00000000000000) (-2.00000000000000,0.000000000000000E+000)
the eigenvalues and some output infomations
(1.41421356237309,1.110223024625158E-016)
(-1.41421356237309,-1.110223024625157E-016) 0 1000
(66.0000000000000,0.000000000000000E+000) 66

and (ii) with ifx:

ifx --version
ifx (IFX) 2023.1.0 20230320
Copyright (C) 1985-2023 Intel Corporation. All rights reserved.

$ ifx -O2 -o test182-ifx.exe -L${MKLROOT}/lib/intel64 -lmkl_intel_lp64 -lmkl_intel_thread -lmkl_core -liomp5 -lpthread -ldl test182.f90
[jdelia@amaral SHORT]$ test182-ifx.exe
aa=
(2.00000000000000,0.000000000000000E+000) (-1.00000000000000,1.00000000000000)
(1.00000000000000,1.00000000000000) (-2.00000000000000,0.000000000000000E+000)
the eigenvalues and some output infomations
(1.41421356237309,1.110223024625158E-016)
(-1.41421356237309,-1.110223024625157E-016) 0 1000
(66.0000000000000,0.000000000000000E+000) 66

Regards.

JorgeD.

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JohnNichols
Valued Contributor III
‎05-12-2023 07:13 AM
1,686 Views
In response to jdelia 
program main
  !use lapack95
  !use blas95
  !implicit real (kind=8)(a-h,o-z)
  implicit none
  integer :: info, lwork, n
  integer :: lwmax, lda, ldvl, ldvr
  parameter (lwmax=1000)
  parameter (n=2)
  parameter (lda=n, ldvl=n, ldvr=n)
  complex (kind=8) :: rk (n,n), aa (n,n)
  complex (kind=8) :: ww (n), vl (ldvl,n), vr (ldvr,n), work (lwmax)
  real (kind=8) :: rwork (2*n)
  external zgeev
  !
  rk(1,1)= 2.0d0
  rk(2,2)=-2.0d0
  rk(1,2)= cmplx (1.0d0, 1.0d0,kind=8)
  rk(2,1)=-cmplx (1.0d0,-1.0d0,kind=8)
  !
  aa=rk
  lwork=-1
  !
  write (*,*)"aa="
  write (*,*) aa
  call zgeev ('v','v',n,aa,lda,ww,vl,ldvl,vr,ldvr,work,lwork,rwork,info)
  lwork = min (lwmax, int (work(1)))
  call zgeev ('v','v',n,aa,lda,ww,vl,ldvl,vr,ldvr,work,lwork,rwork,info)
  !
  write (*,*)"the eigenvalues and some output infomations"
  write (*,*) ww, info, lwmax, work(1), int(work(1))
  !
end program main

A really great human bean, added the facility to this website to nicely format the Fortran code. No idea who that human bean was or is or has been, but it helps us mere human mortals of finite life duration read the code. 

Can I say that you could clean up the parameter declarations into one line instead of multiple lines. It would be easier to read.  

 

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jdelia
New Contributor I
‎05-12-2023 08:19 AM
1,664 Views
In response to JohnNichols

Dear JohnNichols,

You're right but, where can I find info about how to use that facility to nicely format Fortran code?

Regards.

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AlHill
Super User
‎05-12-2023 09:34 AM
1,654 Views

Ask John to tell you about TIDY.

 

Doc (not an Intel employee or contractor)
[Maybe Windows 12 will be better]

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JohnNichols
Valued Contributor III
‎05-12-2023 09:56 AM
1,644 Views
In response to AlHill

Screenshot 2023-05-12 115147.png

In the reply box there are three buttons at the end of the format bar, this button opens a second row and the icon </> lets you input formatted Fortran text. Select the text type as Fortran and we can then look at it.  

pretty standard practice on this site is not to use kind = 8, but the other kind of way of doing it.  

 

 !---------------------------------------------------------------------------------------------------------------------------
    !
    !   Four modules are called from the main program.
    !   Base holds the underlying FORTRAN elements such as dp etc.
    !   Subroutines
    !                   OpenFiles (i,j,k,l,m)
    !                   LineBlank(sw)
    !                   Line(sw)
    !                   Timingline(sw)
    !
    !---------------------------------------------------------------------------------------------------------------------------

    Module Base

    !INTEGER, PARAMETER :: dp = selected_real_kind(30)

    INTEGER, PARAMETER :: dp = selected_real_kind(15, 307)
    INTEGER, PARAMETER :: dpA = selected_real_kind(15, 307)

    INTEGER, PARAMETER :: sw = 2                    !   Output file
    INTEGER, PARAMETER :: srA = 15                  !   output.txt file
    INTEGER, PARAMETER :: st = 14
    INTEGER, PARAMETER :: sa = 3                    !   Output file
    INTEGER, PARAMETER :: smWrite = 4
    INTEGER, PARAMETER :: si = 1
    Integer, parameter :: slog = 9                  !   Log file
    Integer, parameter :: nta = 100                  !   Log file
    Integer, parameter :: outNode = 63                  !   Log file
    Integer, parameter :: inNode = 0                  !   Log file
    Integer, parameter :: NUM = 50                  !   Column Steps for Warner equations

    REAL (KIND=dp), PARAMETER :: gr = 9.806, pi = 3.14159265D0  !   Standard parameters
    REAL (KIND=dp), PARAMETER :: delta = 0.0001                !   Error number of checking for zero

    REAL (KIND=dp), PARAMETER :: deltaS = 0.1                !   Error number of checking for zero

 

 Of course there are variations and the Four Titans of this site will tell you the mistakes they see in my method.  One just has to accept that one is a failure in life and it then is easy to not get upset.  As the father of four daughters I accept constant failure. 

Dr. Hill has made some reference to TIDY.  At the moment, my brain is deep inside Dutch bridges and the reference illudes me, but it may reference some obscure program that does absolutely nothing with blinding speed and Jim will tell you how to make it faster.  If a program can run in less time than it takes to make a cup of tea then you are a failure, tea time is important.  MS 3.31 Fortran and the unnamed computer were perfect for that, a DELL Precision and ONEAPI is a complete failure at making time for tea. 

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JohnNichols
Valued Contributor III
‎05-12-2023 10:03 AM
1,642 Views
In response to JohnNichols

if you are a https://www.peanuts.com/about/linus  this site is not for you, try Fortran discourse. 

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jdelia
New Contributor I
‎05-12-2023 10:38 AM
1,635 Views
In response to JohnNichols

Dear JohnNichols,

  • Ok, thanks a lot for summarizing how to nicely format a fortran code in this site. Maybe it could be included in the FAQ.
  • Yes, I know that it is not recommended to use kind=8, and that there are another ways to do it. 
  • I suspect that TIDY is intended for windows users. While I am OS neutral, I usually use Linux (Fedora).

Thank you very much for the tips.

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