add nbytes

Author: eric496

2. Inspect an Array.ipynb

@@ -196,6 +196,31 @@
    "source": [
     "print(arr.itemsize)"
    ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "### inspect the memory size of an array (in byte)"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 42,
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "48\n"
+     ]
+    }
+   ],
+   "source": [
+    "# arr.nbytes = arr.size * arr.itemsize\n",
+    "print(arr.nbytes)"
+   ]
   }
  ],
  "metadata": {