Using PYOPTSPARSE_IMPORT_SNOPT_FROM

[swryan]

This is not strictly a pyoptsparse issue, but I was trying to exercise the capability offered by the PYOPTSPARSE_IMPORT_SNOPT_FROM environment variable.

I seem to have successfully built the SNOPT library per the instructions here, and created snopt*.so using the provided f2py file, but have not been able to close the loop with pyoptsparse.

As can be seen here on GitHub, I get errors when trying to import snopt as built.

I was hoping someone with some experience using SNOPT in this way with pyoptsparse could point me in the right direction.

Here is the relevant fragment of my script:

            echo "============================================================="
            echo "Building SNOPT"
            echo "============================================================="
            cd SNOPT
            ./configure
            make
            make check

            cd lib
            if [[ "${{ matrix.OS }}" == "ubuntu-latest" ]]; then
              cp /home/runner/work/pyoptsparse/pyoptsparse/pyoptsparse/pySNOPT/source/f2py/snopt.pyf .
            else
              cp /Users/runner/work/pyoptsparse/pyoptsparse/pyoptsparse/pySNOPT/source/f2py/snopt.pyf .
            fi
            python -m numpy.f2py -c -m snopt snopt.pyf

            echo "============================================================="
            echo "Try to import SNOPT"
            echo "============================================================="
            python -c "import snopt"

And here are the results..

Ubuntu/Conda:

=============================================================
Try to import SNOPT
=============================================================
Traceback (most recent call last):
  File "<string>", line 1, in <module>
ImportError: /home/runner/work/pyoptsparse/pyoptsparse/SNOPT/lib/snopt.cpython-312-x86_64-linux-gnu.so: undefined symbol: openunit_

MacOS/Conda:

=============================================================
Try to import SNOPT
=============================================================
Traceback (most recent call last):
  File "<string>", line 1, in <module>
ImportError: dlopen(/Users/runner/work/pyoptsparse/pyoptsparse/SNOPT/lib/snopt.cpython-312-darwin.so, 0x0002): symbol not found in flat namespace '_sqlog_'

[ewu63]

pySNOPT requires a few more things to be linked during compilation (for example the error points to openunit not found. Here is a thread with more clear instructions (which we will try to add to our docs...), in particular note the line

SRC=pyoptsparse/pyoptsparse/pySNOPT
python -m numpy.f2py -m snopt -c ${SRC}/f2py/snopt.pyf ${SRC}/*.f -L${PREFIX}/lib -lsnopt7

The ${SRC}/*.f argument tells f2py to additionally build bindings for these fortran files that are shipped with pyOptSparse.

[swryan]

Thanks again.. I was able to get there... this is what I ended up with:

            cd SNOPT
            ./configure
            make
            make check

            if [[ "${{ matrix.OS }}" == "ubuntu-latest" ]]; then
              PYSNOPT_SOURCE=/home/runner/work/pyoptsparse/pyoptsparse/pyoptsparse/pySNOPT/source/
            else
              PYSNOPT_SOURCE=/Users/runner/work/pyoptsparse/pyoptsparse/pyoptsparse/pySNOPT/source/
            fi

            cp -v $PYSNOPT_SOURCE/*.f src/
            cp -v $PYSNOPT_SOURCE/f2py/snopt.pyf .

            rm src/snopth.f
            rm src/sn27lu77.f
            rm src/sn27lu90.f
            
            python -m numpy.f2py -m snopt -c snopt.pyf src/*.f -L`pwd`/lib -lsnopt7

            python -c "import snopt; print(snopt)"

            export PYOPTSPARSE_IMPORT_SNOPT_FROM=`pwd`

[swryan]

Here is a test workflow, in case it's useful:

https://github.com/swryan/pyoptsparse/blob/test_snopt/.github/workflows/test-snopt.yml

[swryan]

ah great.. let me try that, thanks so much 👍🏼