Write the native state produced by VMEC conversion

python/gvec/scripts/convert_wout.py

@@ -15,6 +15,7 @@
 
 import gvec
 from gvec.util import CaseInsensitiveDict
+from gvec.lib import _state
 
 parser = argparse.ArgumentParser(
     prog="pygvec-convert-wout",
@@ -162,6 +163,9 @@ def convert_vmec_wout(
         )
 
         if rundir is not None:
+            # State initialization suppresses output; publish the converted state explicitly.
+            with gvec.util.chdir(tmpdir):
+                _state.save_statefile()
             shutil.copy(sorted(Path(tmpdir).glob("*State*.dat"))[-1], rundir)
             gvec.util.write_parameters(parameters, rundir / "parameter.ini")
             gvec.util.write_parameters(parameters, rundir / "parameter.toml")

test-CI/unit-pygvec/test_convert_wout.py

@@ -0,0 +1,32 @@
+from pathlib import Path
+
+import netCDF4
+import numpy as np
+import pytest
+
+import gvec
+from gvec.scripts.convert_wout import convert_vmec_wout
+
+
+@pytest.mark.parametrize("signgs", ["neg", "pos"])
+@pytest.mark.parametrize("asymmetric", ["F", "T"])
+def test_converted_wout_state_can_be_reloaded(tmp_path, signgs, asymmetric):
+    source = (
+        Path(__file__).parents[1] / "data" / f"wout_test-signgs-{signgs}-asym{asymmetric}.nc"
+    )
+    convert_vmec_wout(source, tmp_path)
+    (statefile,) = tmp_path.glob("*State*.dat")
+    converted = gvec.load_state(tmp_path / "parameter.ini", statefile)
+    try:
+        position = np.asarray(
+            converted.evaluate("pos", rho=1.0, theta=0.0, zeta=0.0).pos
+        ).reshape(3)
+        # At the boundary and zero angles all sine modes vanish. The original
+        # VMEC Fourier coefficients give an independent geometric readback.
+        with netCDF4.Dataset(source) as wout:
+            radius = np.sum(wout["rmnc"][-1, :])
+            height = np.sum(wout["zmnc"][-1, :]) if "zmnc" in wout.variables else 0.0
+            assert converted.nfp == int(wout["nfp"][:])
+        np.testing.assert_allclose(position, [radius, 0.0, height], rtol=1e-10, atol=1e-12)
+    finally:
+        converted.unbind()