add affine eval function to new echogrambuilder

Author: peter-urban

python/themachinethatgoesping/pingprocessing/watercolumn/echograms/coordinate_system.py

@@ -104,6 +104,20 @@ def initialized(self) -> bool:
         """Whether coordinate system is fully initialized."""
         return self._initialized
 
+    def _affine_eval(self, affine: Tuple[np.ndarray, np.ndarray], nr: int, indices) -> np.ndarray:
+        """Evaluate affine transform for a given ping at sample indices.
+        
+        Args:
+            affine: Tuple of (a, b) arrays from _compute_affine_coefficients.
+            nr: Ping index.
+            indices: Sample index or array of sample indices.
+            
+        Returns:
+            Coordinate values: a[nr] + b[nr] * indices
+        """
+        a, b = affine
+        return a[nr] + b[nr] * np.asarray(indices, dtype=np.float32)
+
     def _compute_affine_coefficients(self, min_vals: np.ndarray, max_vals: np.ndarray) -> Tuple[np.ndarray, np.ndarray]:
         """Compute affine coefficients for: value = a + b * sample_index.
         

python/themachinethatgoesping/pingprocessing/watercolumn/echograms/echogrambuilder_new.py

@@ -1093,15 +1093,15 @@ def get_extent_layers(self, nr, axis_name=None):
 
                 case "Sample number":
                     assert cs.has_sample_nrs, "ERROR: Sample nr values not initialized"
-                    extents[key] = cs.y_indice_to_sample_nr_interpolator[nr]([layer.i0[nr] - 0.5, layer.i1[nr] - 0.5])
+                    extents[key] = cs._affine_eval(cs._affine_sample_to_sample_nr, nr, [layer.i0[nr] - 0.5, layer.i1[nr] - 0.5])
 
                 case "Depth (m)":
                     assert cs.has_depths, "ERROR: Depths values not initialized"
-                    extents[key] = cs.y_indice_to_depth_interpolator[nr]([layer.i0[nr] - 0.5, layer.i1[nr] - 0.5])
+                    extents[key] = cs._affine_eval(cs._affine_sample_to_depth, nr, [layer.i0[nr] - 0.5, layer.i1[nr] - 0.5])
 
                 case "Range (m)":
                     assert cs.has_ranges, "ERROR: Ranges values not initialized"
-                    extents[key] = cs.y_indice_to_range_interpolator[nr]([layer.i0[nr] - 0.5, layer.i1[nr] - 0.5])
+                    extents[key] = cs._affine_eval(cs._affine_sample_to_range, nr, [layer.i0[nr] - 0.5, layer.i1[nr] - 0.5])
 
                 case _:
                     raise RuntimeError(f"Invalid axis_name '{axis_name}'")
@@ -1122,15 +1122,15 @@ def get_limits_layers(self, nr, axis_name=None):
 
                 case "Sample number":
                     assert cs.has_sample_nrs, "ERROR: Sample nr values not initialized"
-                    extents[key] = cs.y_indice_to_sample_nr_interpolator[nr]([layer.i0[nr], layer.i1[nr] - 1])
+                    extents[key] = cs._affine_eval(cs._affine_sample_to_sample_nr, nr, [layer.i0[nr], layer.i1[nr] - 1])
 
                 case "Depth (m)":
                     assert cs.has_depths, "ERROR: Depths values not initialized"
-                    extents[key] = cs.y_indice_to_depth_interpolator[nr]([layer.i0[nr], layer.i1[nr] - 1])
+                    extents[key] = cs._affine_eval(cs._affine_sample_to_depth, nr, [layer.i0[nr], layer.i1[nr] - 1])
 
                 case "Range (m)":
                     assert cs.has_ranges, "ERROR: Ranges values not initialized"
-                    extents[key] = cs.y_indice_to_range_interpolator[nr]([layer.i0[nr], layer.i1[nr] - 1])
+                    extents[key] = cs._affine_eval(cs._affine_sample_to_range, nr, [layer.i0[nr], layer.i1[nr] - 1])
 
                 case _:
                     raise RuntimeError(f"Invalid axis_name '{axis_name}'")