adding np.ix_

Author: negin513

intermediate/indexing/advanced-indexing.ipynb

@@ -110,6 +110,18 @@
     "- *Orthogonal* or *outer* indexing allows for indexing along each dimension independently, treating the indexers as one-dimensional arrays. The principle of outer or orthogonal indexing is that the result mirrors the effect of independently indexing along each dimension with integer or boolean arrays, treating both the indexed and indexing arrays as one-dimensional. This method of indexing is analogous to vector indexing in programming languages like MATLAB, Fortran, and R, where each indexer component independently selects along its corresponding dimension. This is the default behavior in Xarray.\n",
     "\n",
     "\n",
+    ":::\n",
+    "\n",
+    ":::{note} Orthogonal indexing with NumPy\n",
+    ":class: dropdown\n",
+    "\n",
+    "While Pointwise indexing is the default behavior in NumPy, you can achieve orthogonal indexing by using the [`np.ix_` function](https://numpy.org/doc/stable/reference/generated/numpy.ix_.html). This function constructs an open mesh from multiple arrays, allowing you to index along each dimension independently similar to Xarray indexig behavior. For example: \n",
+    "\n",
+    "```python\n",
+    "ixgrid = np.ix_([0, 2, 4], [0, 2, 4])\n",
+    "np_array[ixgrid]\n",
+    "```\n",
+    "\n",
     ":::"
    ]
   },
@@ -138,6 +150,7 @@
     "\n",
     "xr.set_options(display_expand_attrs=False)\n",
     "np.set_printoptions(threshold=10, edgeitems=2)\n",
+    "%config InlineBackend.figure_format='retina'\n",
     "\n",
     "ds = xr.tutorial.load_dataset(\"air_temperature\")\n",
     "da_air = ds.air\n",
@@ -387,6 +400,11 @@
   }
  ],
  "metadata": {
+  "kernelspec": {
+   "display_name": "Python 3 (ipykernel)",
+   "language": "python",
+   "name": "python3"
+  },
   "language_info": {
    "codemirror_mode": {
     "name": "ipython",
@@ -396,7 +414,8 @@
    "mimetype": "text/x-python",
    "name": "python",
    "nbconvert_exporter": "python",
-   "pygments_lexer": "ipython3"
+   "pygments_lexer": "ipython3",
+   "version": "3.12.3"
   },
   "toc": {
    "base_numbering": 1,