From f02daa35dd8033e81fcbeac5174fe478fc52b01f Mon Sep 17 00:00:00 2001
From: Pim Nelissen <pim.nelissen@protonmail.com>
Date: Wed, 15 Apr 2026 08:44:18 +0200
Subject: [PATCH] add parameter JSON export

---
 src/pg_rad/utils/export.py | 20 +++++++++++++++++++-
 1 file changed, 19 insertions(+), 1 deletion(-)

diff --git a/src/pg_rad/utils/export.py b/src/pg_rad/utils/export.py
index 0d9fffd..a476987 100644
--- a/src/pg_rad/utils/export.py
+++ b/src/pg_rad/utils/export.py
@@ -1,9 +1,11 @@
+from dataclasses import asdict
 from datetime import datetime as dt
+import json
 import os
 import logging
 import re
 
-from numpy import array, full_like
+from numpy import array, full_like, ndarray
 from pandas import DataFrame
 
 from pg_rad.simulator.outputs import SimulationOutput
@@ -12,6 +14,13 @@ from pg_rad.simulator.outputs import SimulationOutput
 logger = logging.getLogger(__name__)
 
 
+class NumpyEncoder(json.JSONEncoder):
+    def default(self, obj):
+        if isinstance(obj, ndarray):
+            return obj.tolist()
+        return super().default(obj)
+
+
 def generate_folder_name(sim: SimulationOutput) -> str:
     formatted_sim_name = re.sub(r"\s+", '_',  sim.name.lower())
     folder_name = (
@@ -35,9 +44,18 @@ def save_results(sim: SimulationOutput, folder_name: str) -> None:
     df = generate_df(sim)
     csv_name = generate_csv_name(sim)
     df.to_csv(f"{folder_name}/{csv_name}.csv", index=False)
+    with open(f"{folder_name}/parameters.json", 'w') as f:
+        json.dump(generate_sim_param_dict(sim), f, cls=NumpyEncoder)
     logger.info(f"Simulation output saved to {folder_name}!")
 
 
+def generate_sim_param_dict(sim: SimulationOutput) -> dict:
+    """Parse simulation parameters and hyperparameters to dictionary."""
+    d = asdict(sim)
+    d.pop('count_rate')
+    return d
+
+
 def generate_df(sim: SimulationOutput) -> DataFrame:
     """Parse simulation output to CSV format and the name of CSV."""