fix: crashing when all constraints of a type outside of box

LoopStructural/interpolators/discrete_interpolator.py

@@ -361,13 +361,17 @@ def build_matrix(self, square=True, damp=0.0):
         # which is not ideal.
         max_weight = 0
         for c in self.constraints.values():
+            if len(c["w"]) == 0:
+                continue
             if c["w"].max() > max_weight:
                 max_weight = c["w"].max()
         a = []
         b = []
         rows = []
         cols = []
         for c in self.constraints.values():
+            if len(c["w"]) == 0:
+                continue
             aa = (c["A"] * c["w"][:, None] / max_weight).flatten()
             b.extend((c["B"] * c["w"] / max_weight).tolist())
             mask = aa == 0

tests/unit_tests/interpolator/test_outside_box.py

@@ -11,7 +11,16 @@ def test_outside_box_normal():
         model.data = data
         model.create_and_add_foliation('strati',interpolatortype=interpolator)
         model.update()
-
+def test_outside_box_normal():
+    for interpolator in ['PLI','FDI']:
+        print(f'Running test for {interpolator} with normal constraints')
+        model = GeologicalModel(np.zeros(3),np.ones(3))
+        data = pd.DataFrame([[0.5,0.5,0.5,0,1.,0.,np.nan,'strati'],
+                             [1.5,0.5,0.5,0,1.,0.,np.nan,'strati'],
+                             [0.5,1.5,1.5,0,1.,0.,1.,'strati']],columns=['X','Y','Z','nx','ny','nz','val','feature_name'])
+        model.data = data
+        model.create_and_add_foliation('strati',interpolatortype=interpolator)
+        model.update()
 def test_outside_box_value():
     for interpolator in ['PLI','FDI']:
         print(f'Running test for {interpolator} with normal constraints')