facedetection - catch warning if doesnt tend towards a fit

src/aare/common/face_detection.py

@@ -2,7 +2,8 @@ import json
 import time
 from typing import Tuple, Dict, List, Optional
 import numpy as np
-from scipy.optimize import curve_fit
+from scipy.optimize import curve_fit, OptimizeWarning
+import warnings
 import statistics
 import math
 from aare.common.logger_config import setup_logger
@@ -86,7 +87,11 @@ def fit_cosine(samples: List[Tuple[float, float]]) -> dict:
     bounds = ([-np.inf, 0.0, -math.pi, -np.inf], [np.inf, B_max, math.pi, np.inf])
 
     try:
-        popt, _ = curve_fit(cos_model, degs, ys, p0=[A0, B0, phi0, C0], bounds=bounds, maxfev=10000)
+        with warnings.catch_warnings(record=True) as w:
+            warnings.simplefilter("always", OptimizeWarning)
+            popt, _ = curve_fit(cos_model, degs, ys, p0=[A0, B0, phi0, C0], bounds=bounds, maxfev=10000)
+            if w:
+                logger.debug(f"curve_fit OptimizeWarning: {w[-1].message}")
         logger.info(f"fit cosine: {popt}")
         A, B, phi, C = map(float, popt)
         B = max(0.0, B)