CGE-Core v0.6 ↔ GAMS workflow crosswalk

Contents

CGE-Core v0.6 ↔ GAMS workflow crosswalk#

This is a practitioner-intuition and design-sanity aid, not a requirement that Python imitate GAMS. A public operation should have either a recognizable GAMS counterpart or a short explanation of why the Python object model improves on the serial GAMS discipline.

CGE-Core v0.6	GAMS idiom	Manual discipline automated
`CGE(model=StdCGE(), data=...)`	sets/data/parameters/equations declared before solve	Configures the static economy and its data source.
`model.solve_benchmark(numeraire=("pf","LAB"), redundant=("eqpf","LAB"))`	`pf.fx("LAB") = 1;` + Walras-law equation omission + first `solve`	Applies the Hosoe closure, solves the SAM-replicating benchmark, and protects it behind an `Equilibrium`.
`Equilibrium`	benchmark `.l` levels protected by convention/report parameters	Makes the benchmark structurally read-only at the public API.
`benchmark.scenario("tariff abolition")`	begin/reset an experiment block	Creates an isolated counterfactual without manual reset bookkeeping.
`scenario.set("taum", "BRD", 0)`	parameter assignment; for a Var, `.fx`	Applies a scenario shock.
`scenario.unfix("epsilon")`	release a Var previously fixed in the experiment	Releases only a Var fixed earlier by this Scenario; this is not a general GEMPACK-style closure swap.
`result = scenario.solve()`	second `solve`	Solves the counterfactual and returns an immutable snapshot.
`result.value("Z", "BRD")`	`Z.l("BRD")`	Reads a solved level without traversing the live model.
`result.compare(benchmark)`	hand-built report table	Computes `self-reference` differences and percentage changes consistently.
multiple live `Scenario` objects	no direct serial-script equivalent without manual state management	Python object ownership keeps counterfactuals simultaneously live and isolated.

Terminology layer rule#

benchmark: the SAM-replicating static equilibrium;
scenario / counterfactual / experiment: a static policy solve derived from that benchmark;
baseline: reserved for a reference path in dynamic/forecast contexts rather than the static benchmark solve.