Problem description

Cantera provides a Gaussian1 functor, see C++ documentation that is exposed in the Python API, among others.

The Gaussian1 implementation partially deviates from definitions used in Python samples (fuel_injection.py, test_reactor.py, and the recently adopted nanosecond-pulse-discharge.py).

All Python samples should use the Gaussian1 functor, as it does not require Python callbacks and should result in modest performance gains. It also represents an example for functor use, where the API was updated in Cantera 3.1.