o Add healpix bilinear remapping

Author: rajeeja

docs/user-guide/remapping.ipynb

@@ -692,10 +692,40 @@
     ")"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "id": "9ae38e84",
+   "metadata": {},
+   "source": [
+    "#### Also do a coarse HealPix grid and downsampling with it"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "ec76a7fc-a5ec-412e-841a-ab8abeceb2ab",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "hp_grid = ux.Grid.from_healpix(zoom=2, pixels_only=False)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "e0c96087",
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "downsampling_hp_grid = uxds_120[\"bottomDepth\"].remap.bilinear(\n",
+    "    hp_grid, remap_to=\"face centers\"\n",
+    ")"
+   ]
+  },
   {
    "cell_type": "code",
    "execution_count": null,
-   "id": "8449c7f4-3fd8-4042-89f7-bc72e38e5fdd",
+   "id": "051bd247",
    "metadata": {},
    "outputs": [],
    "source": [
@@ -709,6 +739,11 @@
     "        cmap=ux.cmaps.sequential_blue,\n",
     "    )\n",
     "    * features\n",
+    "    + downsampling_hp_grid.plot(\n",
+    "        title=\"Remapped Bottom Depth (120km to Healpix)\",\n",
+    "        cmap=ux.cmaps.sequential_blue,\n",
+    "    )\n",
+    "    * features\n",
     "    + uxds_120[\"bottomDepth\"].plot(\n",
     "        title=\"Zoomed (120km)\",\n",
     "        xlim=(-10, 10),\n",
@@ -723,21 +758,20 @@
     "        cmap=ux.cmaps.sequential_blue,\n",
     "    )\n",
     "    * features\n",
+    "    + downsampling_hp_grid.plot(\n",
+    "        title=\"Zoomed Remap (120km to Healpix)\",\n",
+    "        xlim=(-10, 10),\n",
+    "        ylim=(-5, 5),\n",
+    "        cmap=ux.cmaps.sequential_blue,  \n",
+    "    )\n",
+    "    * features\n",
     ").opts(fig_size=300).cols(1)"
    ]
-  },
-  {
-   "cell_type": "code",
-   "execution_count": null,
-   "id": "ec76a7fc-a5ec-412e-841a-ab8abeceb2ab",
-   "metadata": {},
-   "outputs": [],
-   "source": []
   }
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 3 (ipykernel)",
+   "display_name": "esmf_env",
    "language": "python",
    "name": "python3"
   },
@@ -751,7 +785,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.12.8"
+   "version": "3.11.11"
   }
  },
  "nbformat": 4,