**bdf2**,
a Python code which
solves one or more ordinary differential equations (ODE)
using BDF2, the (implicit) backward difference formula
of order 2, using fsolve() to solve the implicit equation.

The computer code and data files described and made available on this web page are distributed under the GNU LGPL license.

**bdf2** is available in
a MATLAB version and
a Python version.

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trapezoidal, a Python code which solves one or more ordinary differential equations (ODE) using the (implicit) trapezoidal method.

trapezoidal_explicit, a Python code which solves one or more ordinary differential equations (ODE) using the explicit trapezoidal method.

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- bdf2_test.py, the source code.
- bdf2_test.sh, runs all the tests.
- bdf2_test.txt, the output file.