rxd handles np.float64 and other numpy.generic types (#3808)

* unwrap numpy objects (preserves floats and ints)
* added a test

Author: ramcdougal

share/lib/python/neuron/rxd/rxdmath.py

@@ -750,6 +750,8 @@ def _semi_compile(self, region, instruction):
                 try:
                     items_append(item._semi_compile(region, instruction))
                 except AttributeError:
+                    if isinstance(item, numpy.generic):
+                        item = item.item()
                     items_append(f"{item!r}")
                 counts_append(count)
         result = ""

test/rxd/test_state_reaction.py

@@ -1,4 +1,5 @@
 import pytest
+import numpy as np
 from .testutils import compare_data, tol
 
 
@@ -37,3 +38,17 @@ def test_state_reaction2(neuron_instance):
     h.finitialize(-65)
     h.continuerun(1)
     assert sec(0.5).ca2i == sec(0.5).cai
+
+
+def test_numpy_rate(neuron_instance):
+    """Test a simple rxd.Rate involving a numpy value"""
+    n, rxd, data, save_path = neuron_instance
+    soma = n.Section("soma")
+    soma.L = soma.diam = 10
+    cyt = rxd.Region([soma], name="cyt", nrn_region="i")
+    c = rxd.Species(cyt, name="c", charge=1, initial=0)
+    r = rxd.Rate(c, np.float64(1))
+    n.dt = 0.025
+    n.finitialize(-65)
+    n.fadvance()
+    assert c.nodes[0].concentration == 0.025