diff --git a/webbpsf/gridded_library.py b/webbpsf/gridded_library.py
index b78cc0da..da61f3d6 100644
--- a/webbpsf/gridded_library.py
+++ b/webbpsf/gridded_library.py
@@ -340,7 +340,7 @@ def create_grid(self):
                 if self.fov_pixels % 2 == 0:
                     loc += 0.5  # even arrays must be at a half pixel
 
-                meta["DET_YX{}".format(h)] = (str((loc[1], loc[0])),
+                meta["DET_YX{}".format(h)] = (str((float(loc[1]), float(loc[0]))),
                                               "The #{} PSF's (y,x) detector pixel position".format(h))
 
             meta["NUM_PSFS"] = (self.num_psfs, "The total number of fiducial PSFs")
diff --git a/webbpsf/optics.py b/webbpsf/optics.py
index 7bd26430..c54a1ef7 100644
--- a/webbpsf/optics.py
+++ b/webbpsf/optics.py
@@ -836,7 +836,7 @@ def get_transmission(self, wave):
             else:
                 raise NotImplementedError("invalid name for NIRCam wedge occulter")
 
-            sigmas = scipy.poly1d(polyfitcoeffs)(scalefact)
+            sigmas = np.poly1d(polyfitcoeffs)(scalefact)
 
             sigmar = sigmas * np.abs(y)
             # clip sigma: The minimum is to avoid divide by zero
@@ -1022,7 +1022,7 @@ def _calc_blc_wedge(deg=4, wavelength=2.1e-6):
     sigs = [_width_blc(difflim * ri) for ri in r]
 
     pcs = scipy.polyfit(r, sigs, deg)
-    p = scipy.poly1d(pcs)
+    p = np.poly1d(pcs)
     plt.plot(r, sigs, 'b')
     plt.plot(r, p(r), "r--")
     diffs = (sigs - p(r))
diff --git a/webbpsf/utils.py b/webbpsf/utils.py
index 047ccdb1..fff9e6d5 100644
--- a/webbpsf/utils.py
+++ b/webbpsf/utils.py
@@ -263,9 +263,9 @@ def get_webbpsf_data_path(data_version_min=None, return_version=False):
 
 
 ***************************************************************
-Floating point type information for numpy.float_:
+Floating point type information for numpy.double:
 {finfo_float}
-Floating point type information for numpy.complex:
+Floating point type information for numpy.cdouble:
 {finfo_complex}
 
 ***************************************************************
@@ -418,8 +418,8 @@ def system_diagnostic():
         stsyn=stsynphot_version,
         pysyn=pysynphot_version,
         astropy=astropy_version,
-        finfo_float=numpy.finfo(numpy.float_),
-        finfo_complex=numpy.finfo(numpy.complex_),
+        finfo_float=numpy.finfo(numpy.double),
+        finfo_complex=numpy.finfo(numpy.cdouble),
         numexpr=numexpr_version,
         scipy=scipy.__version__,
         accelerate=accelerate_version,