fix: adding value point save.

TODO there should be a base class for points to share methods

LoopStructural/datatypes/_point.py

@@ -1,12 +1,15 @@
 from dataclasses import dataclass
 import numpy as np
 
+from typing import Optional
+
 
 @dataclass
 class ValuePoints:
     locations: np.ndarray
     values: np.ndarray
     name: str
+    properties: Optional[dict] = None
 
     def to_dict(self):
         return {
@@ -22,12 +25,40 @@ def vtk(self):
         points["values"] = self.values
         return points
 
+    def save(self, filename):
+        filename = str(filename)
+        ext = filename.split('.')[-1]
+        if ext == 'json':
+            import json
+
+            with open(filename, 'w') as f:
+                json.dump(self.to_dict(), f)
+        elif ext == 'vtk':
+            self.vtk().save(filename)
+
+        elif ext == 'geoh5':
+            from LoopStructural.export.geoh5 import add_points_to_geoh5
+
+            add_points_to_geoh5(filename, self)
+        elif ext == 'pkl':
+            import pickle
+
+            with open(filename, 'wb') as f:
+                pickle.dump(self, f)
+        elif ext == 'vs':
+            from LoopStructural.export.gocad import _write_pointset
+
+            _write_pointset(self, filename)
+        else:
+            raise ValueError(f'Unknown file extension {ext}')
+
 
 @dataclass
 class VectorPoints:
     locations: np.ndarray
     vectors: np.ndarray
     name: str
+    properties: Optional[dict] = None
 
     def to_dict(self):
         return {