[00Sibbe]

Hi,

I am new to this forum and also quite new to using OpenFOAM in general and PyFoam in special. PyFoam is a powerful tool and I am glad to be able to take advantage of its additional capabilities. However, when writing my own PyFoam I keep getting the following error:

Traceback (most recent call last):
File "readbb.py", line 2, in <module>
from PyFoam.Execution.BasicRunner import BasicRunner
File "/usr/lib/python2.6/site-packages/PyFoam/Execution/BasicRunner.py", line 14, in <module>
from PyFoam.Basics.DataStructures import makePrimitiveString
File "/usr/lib/python2.6/site-packages/PyFoam/Basics/DataStructures.py", line 5, in <module>
import PyFoam.Basics.FoamFileGenerator
File "/usr/lib/python2.6/site-packages/PyFoam/Basics/FoamFileGenerator.py", line 5, in <module>
from PyFoam.Basics.DataStructures import Vector,Field,Dimension,TupleProxy,DictProxy,Tensor ,SymmTensor,Unparsed,UnparsedList,Codestream,DictR edirection,BinaryList,BoolProxy
ImportError: cannot import name Vector


when I try to import PyFoam libraries at the beginning of a python script, e.g. by:

import os, shutil
from PyFoam.Execution.BasicRunner import BasicRunner

I have python version 2.6.6 installed on a CentOS 6.5 machine, I am using OpenFOAM 2.3.0 and PyFoam 0.6.3 version (installation as root).
I already checked some things recommended at the openfoam wiki homepage .

Can anybody help me to fix this error?
Any help is very appreciated, thank you in advance.

Regards,
Sebastian

[gschaider]

Originally Posted by 00Sibbe

Hi,

I am new to this forum and also quite new to using OpenFOAM in general and PyFoam in special. PyFoam is a powerful tool and I am glad to be able to take advantage of its additional capabilities. However, when writing my own PyFoam I keep getting the following error:

Traceback (most recent call last):
File "readbb.py", line 2, in <module>
from PyFoam.Execution.BasicRunner import BasicRunner
File "/usr/lib/python2.6/site-packages/PyFoam/Execution/BasicRunner.py", line 14, in <module>
from PyFoam.Basics.DataStructures import makePrimitiveString
File "/usr/lib/python2.6/site-packages/PyFoam/Basics/DataStructures.py", line 5, in <module>
import PyFoam.Basics.FoamFileGenerator
File "/usr/lib/python2.6/site-packages/PyFoam/Basics/FoamFileGenerator.py", line 5, in <module>
from PyFoam.Basics.DataStructures import Vector,Field,Dimension,TupleProxy,DictProxy,Tensor ,SymmTensor,Unparsed,UnparsedList,Codestream,DictR edirection,BinaryList,BoolProxy
ImportError: cannot import name Vector


when I try to import PyFoam libraries at the beginning of a python script, e.g. by:

import os, shutil
from PyFoam.Execution.BasicRunner import BasicRunner

I have python version 2.6.6 installed on a CentOS 6.5 machine, I am using OpenFOAM 2.3.0 and PyFoam 0.6.3 version (installation as root).
I already checked some things recommended at the openfoam wiki homepage .

Can anybody help me to fix this error?
Any help is very appreciated, thank you in advance.

Regards,
Sebastian

That is strange. Tried it on two different machines and no problem. And it would break a lot of stuff if there was a problem. Basically what it says is "in DataStructures.py" there is no 'thing' called Vector". Check your file /usr/lib/python2.6/site-packages/PyFoam/Basics/DataStructures.py. There should be a class Vector somewhere. That class has been around for a long time so I don't think it is a "it works for Bernhard because he's got the development version"-issue. Check whether the DataStructures.py you have is the same as in the downloaded tar of PyFoam

[00Sibbe]

Thank you for your feedback, Bernhard.
I have checked the /usr/lib/python2.6/site-packages/PyFoam/Basics/DataStructures.py file as you mentioned and I found the vector structure inside it:

class Vector(FixedLength):
def __init___(self,x,y,z):
FixedLength.__init__(self,[x,y,z])
(...)

It is the same definition as in the downloaded tar. I also did a reinstallation and I am sure not to have manipulated it by myself.

Maybe it is worth mentioning that single PyFoam applications (e.g. pyFoamPlotRunner.py) work as well as does a script that includes libraries from the 'applications' folder of PyFoam.

Best,
Sebastian

[00Sibbe]

I just found out that everything works out fine on my working machine if I download and install PyFoam version 0.6.2 instead.
So from what I've found out so far, the problem seems to have something to do with pyfoam version 0.6.3. But I still don't get why.

Regards,
Sebastian

[gschaider]

Originally Posted by 00Sibbe

I just found out that everything works out fine on my working machine if I download and install PyFoam version 0.6.2 instead.
So from what I've found out so far, the problem seems to have something to do with pyfoam version 0.6.3. But I still don't get why.

Regards,
Sebastian

I can't reproduce your problem with the import you give but with

from PyFoam.Basics import DataStructures

this seems to be a circular-dependency problem. I can work around it with

from PyFoam.Basics import FoamFileGenerator
from PyFoam.Basics import DataStructures

So importing FoamFileGenerator first seems to fix this. I'll have a look how to fix this permanently

Added a ticket on Sourceforge: https://sourceforge.net/p/openfoam-e...etspyfoam/219/

[00Sibbe]

Thanks a lot for this information. It helped and solved the problem! If I start my script with

import os, shutil
from PyFoam.Basics import FoamFileGenerator
from PyFoam.Execution.BasicRunner import BasicRunner

the error message stated above doesn't appear anymore and it also works for PyFoam version 0.6.3. So in fact, it seems to have been a circular-dependency problem.

Anyway starting the python script with

import os, shutil
from PyFoam.Execution.BasicRunner import BasicRunner

didn't give any errors in PyFoam 0.6.2 version. This is what I was trying to express with my last post. So my guess is that inter-dependencies of different pyfoam classes might have changed for the new version

So thank you again,
regards