Excited state importance sampling patch

• Add functionality to add a flag to add in limiting drift term/local energy in order to do excited state DMC using importance sampling

Debugging Patch

• Allowed the g matrix to be a function in fixed-node DMC.
• Allowed restarts with importance sampling

Fixed Node Patch

Additional functionality for fixed node DMC.

Fixed Node DMC

Add fixed node capabilities.

Restart bug fixes

Allow for continuous weights to be added in for restarting DMC sims, add in parent continuous weights to wave function output for continuous weight simulations.

Bug fixes and quality of life improvements

Continuous weighting weights are now returned with wave function, harmonic sampling can have varied mass.

Adiabatic DMC, MPI improvements

Incorporation of simple option to do adiabatic DMC, and speed improvements for MPI4Py based on using chunksize instead of splittiing up the data by myself.

Imp Samp Improvements

Continuous weighting fix for imp sampling and efficiency increase in discrete weighting imp samp.

Atomic Unit Standardization of PyVibDMC

Previously, PyVibDMC file output was in atomic units, but any analysis or reading of that data was done in angstroms or cm-1. Now, the output has remained in atomic units, and the analysis code is by default still in atomic units. One can pass in an optional keyword argument in order to convert the output to angstroms/cm-1.

NOTE: This is not a backwards compatible change. Please be careful of loading in old data or using old code, now the default is atomic units for everything.

Full Changelog: 1.2.3...1.3.0

Chain Rule Efficiency

Made Chain rule more efficient. Based on how it is currently structured, one can now reuse derivatives that have already been calculated.