added dictionary mapping

Author: K-Waks

3) data structures.ipynb

@@ -29,7 +29,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 9,
+   "execution_count": 2,
    "id": "124dfa4d",
    "metadata": {},
    "outputs": [
@@ -67,7 +67,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 10,
+   "execution_count": 3,
    "id": "343cab68",
    "metadata": {},
    "outputs": [
@@ -96,7 +96,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 11,
+   "execution_count": 4,
    "id": "38818fb9",
    "metadata": {},
    "outputs": [
@@ -106,7 +106,7 @@
        "True"
       ]
      },
-     "execution_count": 11,
+     "execution_count": 4,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -117,7 +117,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 12,
+   "execution_count": 5,
    "id": "570adeb9",
    "metadata": {},
    "outputs": [
@@ -127,7 +127,7 @@
        "False"
       ]
      },
-     "execution_count": 12,
+     "execution_count": 5,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -147,7 +147,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 14,
+   "execution_count": 6,
    "id": "9aa27411",
    "metadata": {},
    "outputs": [
@@ -184,7 +184,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 13,
+   "execution_count": 7,
    "id": "f8d946cf",
    "metadata": {},
    "outputs": [
@@ -194,7 +194,7 @@
        "3"
       ]
      },
-     "execution_count": 13,
+     "execution_count": 7,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -215,7 +215,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 21,
+   "execution_count": 8,
    "id": "0b11e898",
    "metadata": {},
    "outputs": [
@@ -225,7 +225,7 @@
        "False"
       ]
      },
-     "execution_count": 21,
+     "execution_count": 8,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -245,7 +245,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 25,
+   "execution_count": 9,
    "id": "3fc754a7",
    "metadata": {},
    "outputs": [
@@ -256,7 +256,7 @@
      "traceback": [
       "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
       "\u001b[0;31mAttributeError\u001b[0m                            Traceback (most recent call last)",
-      "Input \u001b[0;32mIn [25]\u001b[0m, in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0m \u001b[43mmy_tuple\u001b[49m\u001b[38;5;241;43m.\u001b[39;49m\u001b[43mappend\u001b[49m(\u001b[38;5;241m4\u001b[39m)\n",
+      "Cell \u001b[0;32mIn[9], line 1\u001b[0m\n\u001b[0;32m----> 1\u001b[0m my_tuple\u001b[39m.\u001b[39;49mappend(\u001b[39m4\u001b[39m)\n",
       "\u001b[0;31mAttributeError\u001b[0m: 'tuple' object has no attribute 'append'"
      ]
     }
@@ -294,7 +294,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 3,
+   "execution_count": 10,
    "id": "2cd42f05",
    "metadata": {},
    "outputs": [
@@ -311,7 +311,7 @@
        "5"
       ]
      },
-     "execution_count": 3,
+     "execution_count": 10,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -334,7 +334,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 4,
+   "execution_count": 11,
    "id": "ce2034e0",
    "metadata": {},
    "outputs": [
@@ -351,7 +351,7 @@
        "2"
       ]
      },
-     "execution_count": 4,
+     "execution_count": 11,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -374,7 +374,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 6,
+   "execution_count": 12,
    "id": "04796b0e",
    "metadata": {},
    "outputs": [
@@ -384,7 +384,7 @@
        "False"
       ]
      },
-     "execution_count": 6,
+     "execution_count": 12,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -396,7 +396,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 8,
+   "execution_count": 13,
    "id": "eadfbe2c",
    "metadata": {},
    "outputs": [
@@ -406,7 +406,7 @@
        "True"
       ]
      },
-     "execution_count": 8,
+     "execution_count": 13,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -436,7 +436,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 16,
+   "execution_count": 14,
    "id": "07eacb6d",
    "metadata": {},
    "outputs": [
@@ -446,7 +446,7 @@
        "'A red fruit'"
       ]
      },
-     "execution_count": 16,
+     "execution_count": 14,
      "metadata": {},
      "output_type": "execute_result"
     }
@@ -489,7 +489,7 @@
   },
   {
    "cell_type": "code",
-   "execution_count": 18,
+   "execution_count": 15,
    "id": "40a2a490",
    "metadata": {},
    "outputs": [
@@ -519,6 +519,149 @@
     "print(my_dictionary[True])\n",
     "print(my_dictionary['5 is less than 4'])"
    ]
+  },
+  {
+   "attachments": {},
+   "cell_type": "markdown",
+   "id": "b6f9fcd8",
+   "metadata": {},
+   "source": [
+    "## Dictionary mapping"
+   ]
+  },
+  {
+   "attachments": {},
+   "cell_type": "markdown",
+   "id": "01c5f9f7",
+   "metadata": {},
+   "source": [
+    "- Use the `get()` method to get the value of a key."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 16,
+   "id": "28a8b1d7",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "'Sometimes a green fruit'"
+      ]
+     },
+     "execution_count": 16,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "my_dictionary.get(\"apple\")"
+   ]
+  },
+  {
+   "attachments": {},
+   "cell_type": "markdown",
+   "id": "2b129ecb",
+   "metadata": {},
+   "source": [
+    "- You can also specify a default value to be returned with `get()` when a key is not in the dictionary. "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 20,
+   "id": "d1c42d23",
+   "metadata": {},
+   "outputs": [
+    {
+     "data": {
+      "text/plain": [
+       "'One of my favorite foods'"
+      ]
+     },
+     "execution_count": 20,
+     "metadata": {},
+     "output_type": "execute_result"
+    }
+   ],
+   "source": [
+    "my_dictionary.get(\"pancakes\", \"One of my favorite foods\")"
+   ]
+  },
+  {
+   "attachments": {},
+   "cell_type": "markdown",
+   "id": "1d1803f9",
+   "metadata": {},
+   "source": [
+    "- This can be useful in the sort of a `match-case` scenario."
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 21,
+   "id": "a15f1fca",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Starting the program\n"
+     ]
+    }
+   ],
+   "source": [
+    "command = input(\"Enter a command: \")\n",
+    "match command:\n",
+    "    case \"start\":\n",
+    "        print(\"Starting the program\")\n",
+    "    case \"stop\":\n",
+    "        print(\"Stopping the program\")\n",
+    "    case \"help\":\n",
+    "        print(\"Showing the help menu\")\n",
+    "    case _:\n",
+    "        print(\"Invalid command\")"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": 25,
+   "id": "92b28113",
+   "metadata": {},
+   "outputs": [
+    {
+     "name": "stdout",
+     "output_type": "stream",
+     "text": [
+      "Starting the program\n",
+      "\n",
+      "Invalid command\n"
+     ]
+    }
+   ],
+   "source": [
+    "def switch(input):\n",
+    "\n",
+    "    command = {\"start\": \"Starting the program\",\n",
+    "            \"stop\": \"Stopping the program\",\n",
+    "            \"help\": \"Showing the help menu\"}\n",
+    "\n",
+    "    return command.get(input, \"Invalid command\")\n",
+    "\n",
+    "print(switch(\"start\"))\n",
+    "print()\n",
+    "print(switch(\"pause\"))"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "id": "6d45948b",
+   "metadata": {},
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {