seamm_mdi

A reusable MDI driver facility for SEAMM. It lets a SEAMM step launch a quantum-chemistry (or other) engine once and drive it for many energy/force evaluations over the MDI protocol, instead of re-launching the code for every geometry.

The MDIEngine class is the driver: it listens on a TCP port, launches the engine (which connects back), and exposes a small, unit-aware API:

from seamm_mdi import MDIEngine

with MDIEngine(build_argv, elements=[8, 1, 1]) as engine:
    engine.set_coordinates(xyz, units="Å")
    e = engine.energy(units="kcal/mol")
    f = engine.forces(units="kcal/mol/Å")

build_argv(hostname, port) returns the argv that launches the engine wrapper (e.g. from a program step's get_mdi_engine_command), pointed at the driver's hostname/port. Unit conversions are handled inside MDIEngine (seamm_util.Q_); the default units are MDI-native (bohr, hartree, hartree/bohr).

Status: local-mode (localhost) first cut. Remote/queue launching via the SEAMM executor is planned.