Prevent other possible occurances of this bug

scopesim/optics/fov.py

@@ -3,6 +3,7 @@
 import logging
 from copy import deepcopy
 from itertools import chain
+from collections.abc import Iterable
 
 import numpy as np
 from scipy.interpolate import interp1d
@@ -389,6 +390,10 @@ def make_image_hdu(self, use_photlam=False):
 
         for flux, weight, x, y in self._make_image_tablefields(fluxes):
             if utils.from_currsys(self.meta["sub_pixel"]):
+                # These x and y should not be arrays when sub_pixel is
+                # enabled, it is therefore not necessary to deploy the fix
+                # below in the else-branch.
+                assert not isinstance(x, Iterable), "x must be an integer"
                 canvas_image_hdu.data[y, x] += flux * weight
             else:
                 # Mask out any stars that were pushed out of the fov by rounding
@@ -592,6 +597,8 @@ def make_cube_hdu(self):
                                    start=canvas_cube_hdu.data)
 
         for flux, x, y in self._make_cube_tablefields(specs):
+            # To prevent adding array values in this manner.
+            assert not isinstance(x, Iterable), "x should be integer"
             canvas_cube_hdu.data[:, y, x] += flux
 
         canvas_cube_hdu.data = sum(self._make_cube_backfields(specs),

scopesim/optics/image_plane_utils.py

@@ -2,6 +2,7 @@
 import logging
 from typing import Tuple
 from itertools import product
+from collections.abc import Iterable
 
 import numpy as np
 from astropy import units as u
@@ -328,6 +329,8 @@ def _add_intpixel_sources_to_canvas(canvas_hdu, xpix, ypix, flux, mask):
     canvas_hdu.header["comment"] = f"Adding {len(flux)} int-pixel files"
     for xpx, ypx, flx, msk in zip(xpix.astype(int), ypix.astype(int),
                                   flux, mask):
+        # To prevent adding array values in this manner.
+        assert not isinstance(xpx, Iterable), "xpx should be integer"
         canvas_hdu.data[ypx, xpx] += flx.value * msk
 
     return canvas_hdu
@@ -341,6 +344,8 @@ def _add_subpixel_sources_to_canvas(canvas_hdu, xpix, ypix, flux, mask):
             xx, yy, fracs = sub_pixel_fractions(xpx, ypx)
             for x, y, frac in zip(xx, yy, fracs):
                 if y < canvas_shape[0] and x < canvas_shape[1]:
+                    # To prevent adding array values in this manner.
+                    assert not isinstance(x, Iterable), "x should be integer"
                     canvas_hdu.data[y, x] += frac * flx.value
 
     return canvas_hdu

scopesim/source/source_utils.py

@@ -1,4 +1,5 @@
 import logging
+from collections.abc import Iterable
 
 import numpy as np
 from astropy import wcs, units as u
@@ -146,8 +147,10 @@ def make_imagehdu_from_table(x, y, flux, pix_scale=1*u.arcsec):
     yint, xint  = ypix.astype(int), xpix.astype(int)
 
     image = np.zeros((np.max(xint) + 1, np.max(yint) + 1))
-    for ii in range(len(xint)):
-        image[xint[ii], yint[ii]] += flux[ii]
+    for xi, yi, fluxi in zip(xint, yint, flux):
+        # To prevent adding array values in this manner.
+        assert not isinstance(xi, Iterable), "xi should be integer"
+        image[xi, yi] += fluxi
 
     hdu = fits.ImageHDU(data=image)
     hdu.header.extend(the_wcs.to_header())