C-integrators not working with recent versions of swig

[Paw]

Dear all,

I cannot get c-integrators to work with recent versions of swig.
I have tried with swig3.0.10 (debian strech included) and the latest swig3.0.12.

When I run examples/Dopri_backwards_test.py I get the error

Error in importing compiled vector field and integrator.
Did you compile the RHS C code?
Traceback (most recent call last):
  File "Dopri_backwards_test.py", line 23, in <module>
    trajf = ode.compute('testf')
  File "/home/paw/.local/lib/python2.7/site-packages/PyDSTool/Generator/Dopri_ODEsystem.py", line 463, in compute
    extraSpace=self.algparams['extraspace'],
  File "/home/paw/.local/lib/python2.7/site-packages/PyDSTool/Generator/Dopri_ODEsystem.py", line 45, in __init__
    modname, *imp.find_module(modname, ["dop853_temp"]))
  File "dop853_temp/dop853_my_ode_vf.py", line 17, in <module>
    _dop853_my_ode_vf = swig_import_helper()
  File "dop853_temp/dop853_my_ode_vf.py", line 16, in swig_import_helper
    return importlib.import_module('_dop853_my_ode_vf')
  File "/usr/lib/python2.7/importlib/__init__.py", line 37, in import_module
    __import__(name)
ImportError: No module named _dop853_my_ode_vf

If I install swig2.0.12(latest swig2) it works as expected. I have not tried with earlier versions of swig3.
If others have the same problem, releases of swig are found here:
https://sourceforge.net/projects/swig/files/swig/

best,
Paw

[clas]

i have compilation issues too. Everything else works fine.

What version of PyDSTool are you using?

[clas]

I should have added that I am using SWIG 3 (now).

[clas]

Ok. I tried to use swig 2.0. Did not work. I get the following set of error messages that I cannot (yet) decode...any help would be (much) appreciated.

---

clasajacobson@clasajacobson-Oryx-Pro:~/Downloads/pydstool-master/examples$ python3 Dopri_backwards_test.py

---

Present limitation of Python: Cannot rebuild library
without exiting Python and deleting the shared library
/home/clasajacobson/Downloads/pydstool-master/examples/_dop853_my_ode_vf.so
by hand! If you made any changes to the system you should
not proceed with running the integrator until you quit
and rebuild.

---

Did not compile shared library.
Error in importing compiled vector field and integrator.
Did you compile the RHS C code?
Traceback (most recent call last):
File "dop853_temp/dop853_my_ode_vf.py", line 14, in swig_import_helper
return importlib.import_module(mname)
File "/usr/lib/python3.6/importlib/init.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap="">", line 994, in _gcd_import
File "<frozen importlib._bootstrap="">", line 971, in _find_and_load
File "<frozen importlib._bootstrap="">", line 953, in _find_and_load_unlocked
ModuleNotFoundError: No module named '_dop853_my_ode_vf'</frozen></frozen></frozen>

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "Dopri_backwards_test.py", line 23, in <module>
trajf = ode.compute('testf')
File "/usr/local/lib/python3.6/dist-packages/PyDSTool-0.90.2-py3.6.egg/PyDSTool/Generator/Dopri_ODEsystem.py", line 463, in compute
extraSpace=self.algparams['extraspace'],
File "/usr/local/lib/python3.6/dist-packages/PyDSTool-0.90.2-py3.6.egg/PyDSTool/Generator/Dopri_ODEsystem.py", line 45, in init
modname, *imp.find_module(modname, ["dop853_temp"]))
File "/usr/lib/python3.6/imp.py", line 235, in load_module
return load_source(name, filename, file)
File "/usr/lib/python3.6/imp.py", line 172, in load_source
module = _load(spec)
File "<frozen importlib._bootstrap="">", line 684, in _load
File "<frozen importlib._bootstrap="">", line 665, in _load_unlocked
File "<frozen importlib._bootstrap_external="">", line 678, in exec_module
File "<frozen importlib._bootstrap="">", line 219, in _call_with_frames_removed
File "dop853_temp/dop853_my_ode_vf.py", line 17, in <module>
_dop853_my_ode_vf = swig_import_helper()
File "dop853_temp/dop853_my_ode_vf.py", line 16, in swig_import_helper
return importlib.import_module('_dop853_my_ode_vf')
File "/usr/lib/python3.6/importlib/init.py", line 126, in import_module
return _bootstrap._gcd_import(name[level:], package, level)
File "<frozen importlib._bootstrap="">", line 994, in _gcd_import
File "<frozen importlib._bootstrap="">", line 971, in _find_and_load
File "<frozen importlib._bootstrap="">", line 953, in _find_and_load_unlocked
ModuleNotFoundError: No module named '_dop853_my_ode_vf'
clasajacobson@clasajacobson-Oryx-Pro:~/Downloads/pydstool-master/examples$ </frozen></frozen></frozen></module></frozen></frozen></frozen></frozen></module>

[Paw]

Five years later, I am using PyDSTool again. And I spend some time trying to figure out what I should do about this error

Did you compile the RHS C code?
Traceback (most recent call last):
  File "pydstool/examples/Dopri_backwards_test.py", line 23, in <module>
    trajf = ode.compute('testf')
  File "/root/projects/pydstool-ex/lib/python3.7/site-packages/PyDSTool-0.90.2-py3.7.egg/PyDSTool/Generator/Dopri_ODEsystem.py", line 465, in compute
    extraSpace=self.algparams['extraspace'],
  File "/root/projects/pydstool-ex/lib/python3.7/site-packages/PyDSTool-0.90.2-py3.7.egg/PyDSTool/Generator/Dopri_ODEsystem.py", line 46, in __init__
    package='dop853_temp',
    ...
    ModuleNotFoundError: No module named 'dop853_temp'

It turns out we have to run the files from the folder they are in, ie.

cd /path/to/pydstool/examples
python3 Dopri_backwards_test.py

I didn't read the error message properly and thought it might be a swig error. But from https://github.com/robclewley/pydstool/issues/140 we know that all swig >= 2 are supported(even swig 4).