F2PY and multi-dimension arrays - unexpected array size error
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Hi I am helping out with a Python and Fortran project. Let me give you some background: * Fortran source: C Bergstrom FCC C User subroutine VUMAT subroutine VUMAT( C Read only - * nblock, ndir, nshr, nstatev, nprops, * stepTime, dt, * props, * density, strainInc, * tempOld, * stressOld, stateOld, enerInternOld, enerInelasOld, C Write only - * stressNew, stateNew, enerInternNew, enerInelasNew ) C include 'vaba_param.inc' C dimension props(nprops), 1 density(nblock), strainInc(nblock,ndir+nshr), 2 tempOld(nblock), 5 stressOld(nblock,ndir+nshr), stateOld(nblock,nstatev), 6 enerInternOld(nblock), enerInelasOld(nblock), 2 stressNew(nblock,ndir+nshr), stateNew(nblock,nstatev), 3 enerInternNew(nblock), enerInelasNew(nblock) * Corresponding .pyf integer :: nblock integer :: ndir integer :: nshr integer :: nstatev integer :: nprops real :: steptime real :: dt real dimension(nprops) :: props real dimension(nblock) :: density real dimension(nblock,ndir+nshr) :: straininc real dimension(nblock) :: tempold real dimension(nblock,ndir+nshr) :: stressold real dimension(nblock,nstatev) :: stateold real dimension(nblock) :: enerinternold real dimension(nblock) :: enerinelasold real dimension(nblock,ndir+nshr),intent(out) :: stressnew real dimension(nblock,nstatev),intent(out) :: statenew real dimension(nblock),intent(out) :: enerinternnew real dimension(nblock),intent(out) :: enerinelasnew * Python source with call of Fortran routine: nblock = 1 ndir = 3 nshr = 3 nstatev = 3 nprops = 11 stepTime = 1 dt = 1 props = np.array([10, 0.5, 1e10, 5, 1e12, 3e-6, 8e-6, 27, 2], float) density = np.array([[7.8e3]], float) strainInc = np.array([[1,-0.5,-0.5,0,0,0]], float) tempOld = np.array([[1]], float) stressOld = np.array([[1,1,1,1,1,1]], float) stateOld = np.array([[1,1,1]], float) enerInternOld = np.array([1], float) enerInelasOld = np.array([1], float) stressNew = np.array([[]], float) stateNew = np.array([[]], float) enerInternNew = np.array([[]], float) enerInelasNew = np.array([[]], float) stressNew, stateNew, enerInternNew, enerInelasNew = vumat(nblock, ndir, nshr, nstatev, nprops, stepTime, dt, props, density, strainInc, tempOld, stressOld, stateOld, enerInternOld, enerInelasOld) When trying to run with Python 2.7 I get: olof@ubuntu:~$ ./demo.py unexpected array size: new_size=4, got array with arr_size=1 Traceback (most recent call last): File "./demo.py", line 33, in <module> main() File "./demo.py", line 30, in main stressNew, stateNew, enerInternNew, enerInelasNew = vumat(nblock, ndir, nshr, nstatev, nprops, stepTime, dt, props, density, strainInc, tempOld, stressOld, stateOld, enerInternOld, enerInelasOld) VUMAT_Bergstrom_FCC.error: failed in converting 9th argument `stressold' of VUMAT_Bergstrom_FCC.vumat to C/Fortran array Other stuff: * python 2.7.6 * numpy/f2py 1.8.2 * gcc/gfortran 4.8.2 * ubuntu 14.04 LTS 32-bit I have tried to google, read the f2py manual, fortran tutorials etc, but to no avail. I must also admit that my knowledge in python is so-so and fortran even less(!). What is the missing statement/syntax that I can’t get correct? Your humble programmer, Olof
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Hello, the project is already successfully completed, but I thought for the completeness (and documentation) give myself an answer on what I did wrong and what the correct solution was. I. I didn’t realise that parameter ordering was crucial. Somehow I just had forgotten this knowledge, but not matter why I did. So after some talk with my colleagues I did finally sort that out. II. You can integrate Python and FORTRAN in two different ways: inline with Cf2py or with signature files. The Numpy and f2py documentation describes the Cf2py solution very well. But my project asked for *no* modification of the FORTRAN source files. So I had to enter the undocumented arena. Lesson learnt: When using the signature file option f2py will effectively re-sort all the parameters in the following order: * integer * real * character * real dimension So the real/correct parameter order will be shown inside if Python when using:
print (func.___doc___)
If I only had known this in the beginning… ;) Al the best, Olof Backing — Olof Backing Sr Open Source Specialist Combitech AB Box 1004 • SE-164 21 KISTA • Sweden Visiting address Torshamnsgatan 30C Phn +46 8 580 861 95 • Mobile +46 73 437 61 95 olof.backing@combitech.se • www.combitech.se
On 03 Feb 2015, at 18:51, Backing Olof <olof.backing@combitech.se> wrote:
Hi I am helping out with a Python and Fortran project. Let me give you some background:
* Fortran source: C Bergstrom FCC C User subroutine VUMAT subroutine VUMAT( C Read only - * nblock, ndir, nshr, nstatev, nprops, * stepTime, dt, * props, * density, strainInc, * tempOld, * stressOld, stateOld, enerInternOld, enerInelasOld, C Write only - * stressNew, stateNew, enerInternNew, enerInelasNew ) C include 'vaba_param.inc' C dimension props(nprops), 1 density(nblock), strainInc(nblock,ndir+nshr), 2 tempOld(nblock), 5 stressOld(nblock,ndir+nshr), stateOld(nblock,nstatev), 6 enerInternOld(nblock), enerInelasOld(nblock), 2 stressNew(nblock,ndir+nshr), stateNew(nblock,nstatev), 3 enerInternNew(nblock), enerInelasNew(nblock)
* Corresponding .pyf integer :: nblock integer :: ndir integer :: nshr integer :: nstatev integer :: nprops real :: steptime real :: dt real dimension(nprops) :: props real dimension(nblock) :: density real dimension(nblock,ndir+nshr) :: straininc real dimension(nblock) :: tempold real dimension(nblock,ndir+nshr) :: stressold real dimension(nblock,nstatev) :: stateold real dimension(nblock) :: enerinternold real dimension(nblock) :: enerinelasold real dimension(nblock,ndir+nshr),intent(out) :: stressnew real dimension(nblock,nstatev),intent(out) :: statenew real dimension(nblock),intent(out) :: enerinternnew real dimension(nblock),intent(out) :: enerinelasnew
* Python source with call of Fortran routine: nblock = 1 ndir = 3 nshr = 3 nstatev = 3 nprops = 11 stepTime = 1 dt = 1 props = np.array([10, 0.5, 1e10, 5, 1e12, 3e-6, 8e-6, 27, 2], float) density = np.array([[7.8e3]], float) strainInc = np.array([[1,-0.5,-0.5,0,0,0]], float) tempOld = np.array([[1]], float) stressOld = np.array([[1,1,1,1,1,1]], float) stateOld = np.array([[1,1,1]], float) enerInternOld = np.array([1], float) enerInelasOld = np.array([1], float)
stressNew = np.array([[]], float) stateNew = np.array([[]], float) enerInternNew = np.array([[]], float) enerInelasNew = np.array([[]], float)
stressNew, stateNew, enerInternNew, enerInelasNew = vumat(nblock, ndir, nshr, nstatev, nprops, stepTime, dt, props, density, strainInc, tempOld, stressOld, stateOld, enerInternOld, enerInelasOld)
When trying to run with Python 2.7 I get: olof@ubuntu:~$ ./demo.py unexpected array size: new_size=4, got array with arr_size=1 Traceback (most recent call last): File "./demo.py", line 33, in <module> main() File "./demo.py", line 30, in main stressNew, stateNew, enerInternNew, enerInelasNew = vumat(nblock, ndir, nshr, nstatev, nprops, stepTime, dt, props, density, strainInc, tempOld, stressOld, stateOld, enerInternOld, enerInelasOld) VUMAT_Bergstrom_FCC.error: failed in converting 9th argument `stressold' of VUMAT_Bergstrom_FCC.vumat to C/Fortran array
Other stuff: * python 2.7.6 * numpy/f2py 1.8.2 * gcc/gfortran 4.8.2 * ubuntu 14.04 LTS 32-bit
I have tried to google, read the f2py manual, fortran tutorials etc, but to no avail. I must also admit that my knowledge in python is so-so and fortran even less(!). What is the missing statement/syntax that I can’t get correct?
Your humble programmer, Olof
participants (1)
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Backing Olof