Installing bfsccylinder

From the distributed packages

Install from the distributed packages, with the dependencies NumPy, SciPy and composites, by simply doing:

python -m pip install bfsccylinder

From the source code

The two elements are written in Cython, in the extension modules bfsccylinder.bfsccylinder and bfsccylinder.bfsccylinder_sanders, translated to C++ and compiled when the package is built, such that installing from the source code requires a C++ compiler, e.g. Microsoft Visual C++ on Windows, GCC on Linux or Clang on macOS. The package metadata, with the version, and the build requirements, setuptools and Cython, are in pyproject.toml; pip installs the build requirements in an isolated environment:

python -m pip install .

The requirements of the tests and of the build, including Cython and pytest, are listed in requirements.txt:

python -m pip install -r requirements.txt

To build in place, for running the tests from the source tree, which also writes bfsccylinder/version.py with the version of pyproject.toml:

python setup.py build_ext --inplace

and the tests with:

python -m pytest tests

requirements.txt also lists structsolve, which solves the nonlinear static analysis of the tests and of the examples and the linear buckling problems of tests/test_follower_pressure_validation.py, see Analyses. It is a requirement of the tests and of the examples of the documentation only: bfsccylinder does not import it, and it is not installed with bfsccylinder, not being in the dependencies of pyproject.toml. The tests and the examples require structsolve 0.10.0 or newer: Crisfield’s convergence criterion as default, the residual \(\boldsymbol{R} = \boldsymbol{F}_{int} - \lambda \boldsymbol{F}_{ext}\) of the examples of Analyses, and the Riks method with a stop criterion on a displacement, the inertia of the tangent stiffness matrix and the branch switching of the tutorial of the post-buckling of a cylinder.

setup.py compiles with /O2 on Windows and with -O3 -fno-math-errno on Linux and macOS, without flags that change the floating-point results, e.g. -ffast-math, or that tie the binaries to the processor that built them, e.g. -march=native. On Linux it also links with -static-libgcc -static-libstdc++.

A build for the coverage of the Cython code, with line tracing and without optimization, is requested with CYTHON_TRACE_NOGIL in the environment or with:

python setup.py build_ext --inplace --force --define CYTHON_TRACE

as in run_setup_coverage.bat. setup.py regenerates the C++ file when it was generated in the other mode, with or without line tracing.

Building the documentation

The documentation requires Sphinx, numpydoc, nbsphinx and the PyData Sphinx theme, and the package built in place, see above:

python -m pip install sphinx numpydoc nbsphinx pydata-sphinx-theme
cd doc
make html