api: add option to inject without increment

devito/operations/interpolators.py

@@ -166,18 +166,20 @@ class Injection(UnevaluatedSparseOperation):
 
     __rargs__ = ('field', 'expr', 'implicit_dims') + UnevaluatedSparseOperation.__rargs__
 
-    def __new__(cls, field, expr, implicit_dims, interpolator):
+    def __new__(cls, field, expr, increment, implicit_dims, interpolator):
         obj = super().__new__(cls, interpolator)
 
         # TODO: unused now, but will be necessary to compute the adjoint
         obj.field = field
         obj.expr = expr
+        obj.increment = increment
         obj.implicit_dims = implicit_dims
 
         return obj
 
     def operation(self, **kwargs):
         return self.interpolator._inject(expr=self.expr, field=self.field,
+                                         increment=self.increment,
                                          implicit_dims=self.implicit_dims)
 
     def __repr__(self):
@@ -372,7 +374,7 @@ def interpolate(self, expr, increment=False, self_subs=None, implicit_dims=None)
 
     @check_radius
     @check_coords
-    def inject(self, field, expr, implicit_dims=None):
+    def inject(self, field, expr, increment=True, implicit_dims=None):
         """
         Generate equations injecting an arbitrary expression into a field.
 
@@ -387,7 +389,7 @@ def inject(self, field, expr, implicit_dims=None):
             injection expression, but that should be honored when constructing
             the operator.
         """
-        return Injection(field, expr, implicit_dims, self)
+        return Injection(field, expr, increment, implicit_dims, self)
 
     def _interpolate(self, expr, increment=False, self_subs=None, implicit_dims=None):
         """
@@ -439,7 +441,7 @@ def _interpolate(self, expr, increment=False, self_subs=None, implicit_dims=None
 
         return temps + summands + last
 
-    def _inject(self, field, expr, implicit_dims=None):
+    def _inject(self, field, expr, increment=True, implicit_dims=None):
         """
         Generate equations injecting an arbitrary expression into a field.
 
@@ -489,9 +491,10 @@ def _inject(self, field, expr, implicit_dims=None):
                                            pos_only=variables, subdomain=subdomain)
 
         # Substitute coordinate base symbols into the interpolation coefficients
-        eqns = [Inc(_field.xreplace(idx_subs),
-                    (self._weights(subdomain=subdomain) * _expr).xreplace(idx_subs),
-                    implicit_dims=implicit_dims)
+        ecls = Inc if increment else Eq
+        eqns = [ecls(_field.xreplace(idx_subs),
+                     (self._weights(subdomain=subdomain) * _expr).xreplace(idx_subs),
+                     implicit_dims=implicit_dims)
                 for (_field, _expr) in zip(fields, _exprs, strict=True)]
 
         return temps + eqns

examples/seismic/self_adjoint/sa_03_iso_correctness.ipynb

@@ -578,9 +578,9 @@
      "output_type": "stream",
      "text": [
       "Operator `IsoFwdOperator` ran in 0.04 s\n",
-      "No source type defined, returning uninitiallized (zero) source\n",
+      "No source type defined, returning uninitialized (zero) source\n",
       "Operator `IsoAdjOperator` ran in 0.03 s\n",
-      "No source type defined, returning uninitiallized (zero) source\n",
+      "No source type defined, returning uninitialized (zero) source\n",
       "Operator `IsoAdjOperator` ran in 0.03 s\n"
      ]
     },
@@ -639,7 +639,7 @@
      "output_type": "stream",
      "text": [
       "Operator `IsoFwdOperator` ran in 0.03 s\n",
-      "No source type defined, returning uninitiallized (zero) source\n",
+      "No source type defined, returning uninitialized (zero) source\n",
       "Operator `IsoAdjOperator` ran in 0.03 s\n"
      ]
     },

examples/seismic/utils.py

@@ -194,7 +194,7 @@ def src(self):
     def new_src(self, name='src', src_type='self', coordinates=None):
         coords = coordinates or self.src_positions
         if self.src_type is None or src_type is None:
-            warning("No source type defined, returning uninitiallized (zero) source")
+            warning("No source type defined, returning uninitialized (zero) source")
             src = PointSource(name=name, grid=self.grid,
                               time_range=self.time_axis, npoint=self.nsrc,
                               coordinates=coords,

tests/test_interpolation.py

@@ -440,6 +440,27 @@ def test_inject(shape, coords, result, npoints=19):
     assert np.allclose(a.data[indices], result, rtol=1.e-5)
 
 
+@pytest.mark.parametrize('shape, coords', [
+    ((11, 11), [(.1, .9), (.4, .4)]),
+    ((11, 11, 11), [(.1, .9), (.4, .4), (.4, .4)])
+])
+def test_inject_no_incr(shape, coords, npoints=9):
+    a = unit_box(shape=shape)
+    a.data[:] = 2.
+    p = points(a.grid, coords, npoints=npoints)
+
+    p.data[:] = 3.
+    expr = p.inject(a, p, increment=False)
+    op = Operator(expr, subs=a.grid.spacing_map)
+
+    op(a=a)
+
+    indices = [slice(4, 5, 1) for _ in coords]
+    indices[0] = slice(1, -1, 1)
+    # Should be 3 at the points
+    assert np.allclose(a.data[indices], 3, rtol=1.e-5)
+
+
 @pytest.mark.parametrize('shape, coords, nexpr, result', [
     ((11, 11), [(.05, .95), (.45, .45)], 1, 1.),
     ((11, 11), [(.05, .95), (.45, .45)], 2, 1.),