Make interpolation work with len 1 arrays.

cosmic_dustbox/crefin.py

@@ -122,20 +122,22 @@ class Crefin(object):
             if bounds_error and not a_bounds_error:
                 def f(aa, lam):
                     r = _np.clip(aa, _np.amin(a), _np.amax(a))
-                    rowind_unsorted = _np.argsort(r)
-                    colind_unsorted = _np.argsort(lam)
-                    return (
-                        rinterpolation(lam, r)
-                        + 1j*iinterpolation(lam, r))[
-                            rowind_unsorted][:, colind_unsorted]
+                    n = rinterpolation(lam, r) + 1j*iinterpolation(lam, r)
+                    if _np.prod(r.shape)*_np.prod(lam.shape) > 1:
+                        rowind_unsorted = _np.argsort(r)
+                        colind_unsorted = _np.argsort(lam)
+                        return n[rowind_unsorted][:, colind_unsorted]
+                    else:
+                        return _np.atleast_2d(n)
             else:
                 def f(a, lam):
-                    rowind_unsorted = _np.argsort(lam)
-                    colind_unsorted = _np.argsort(r)
-                    return (
-                        rinterpolation(lam, a)
-                        + 1j*iinterpolation(lam, a))[
-                            rowind_unsorted][:, colind_unsorted]
+                    n = rinterpolation(lam, a) + 1j*iinterpolation(lam, a)
+                    if _np.prod(r.shape)*_np.prod(lam.shape) > 1:
+                        rowind_unsorted = _np.argsort(lam)
+                        colind_unsorted = _np.argsort(r)
+                        return n[rowind_unsorted][:, colind_unsorted]
+                    else:
+                        return _np.atleast_2d(n)
         return cls(f)
 
 

cosmic_dustbox/tests/test_crefin.py

@@ -52,6 +52,21 @@ class TestFromData(TestCase):
         a = crefin.Crefin.fromData(c.a2, c.lam2, c.n2)
         return
 
+    def test_single_element(self):
+        c = self.__class__
+        a = crefin.Crefin.fromData(c.a2, c.lam2, c.n2)
+        n = a(
+            np.array([1e-9])*u.micron,
+            np.array([8])*u.micron
+        )
+        self.assertTrue
+        return
+
+    def test_single_element_no_bounds(self):
+        c = self.__class__
+        a = crefin.Crefin.fromData(c.a2, c.lam2, c.n2)
+        return
+
     def test_normal_no_bounds(self):
         c = self.__class__
         a = crefin.Crefin.fromData(c.a2, c.lam2, c.n2,