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    "(lists)=\n",
    "# Lists\n",
    "``` {index} Lists (python)\n",
    "```\n",
    "A list is an object that contains multiple elements in defined order (called an **index** number). The syntax is:\n",
    "\n",
    "```\n",
    "    l = [element0, element1, element2, element3, ...]\n",
    "```\n",
    "    \n",
    "Note that indexing in python starts at 0! To extract a specific element or part of the list, we can use slicing syntax:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "1\n",
      "[5, 9, 7, 11]\n",
      "[1, 5]\n",
      "<class 'list'>\n"
     ]
    }
   ],
   "source": [
    "l = [1, 3, 5, 9, 7, 11]\n",
    "\n",
    "# Print first element (index 0!)\n",
    "print(l[0])\n",
    "\n",
    "# Print elements three to six (not inclusive), returns a list\n",
    "print(l[2:6])\n",
    "\n",
    "# Print every second element but the last two excluded\n",
    "print(l[:-3:2])\n",
    "\n",
    "# Print what class l is\n",
    "print(type(l))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "The same operations can be done to lists of strings:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "potatoes\n",
      "['apples', 'bananas', 'milk', 'juice']\n",
      "['potatoes', 'apples']\n",
      "<class 'list'>\n"
     ]
    }
   ],
   "source": [
    "shopping_list = [\"potatoes\", \"cucumber\", \"apples\",\n",
    "                 \"bananas\", \"milk\", \"juice\"]\n",
    "\n",
    "# Print first element\n",
    "print(shopping_list[0])\n",
    "\n",
    "# Print elements three to six, returns a lis\n",
    "print(shopping_list[2:6])\n",
    "\n",
    "# Print every other elements but the last two excluded\n",
    "print(shopping_list[0:-3:2])\n",
    "\n",
    "# Returns class list\n",
    "print(type(shopping_list))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Other operations on lists:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "6\n",
      "[1, 3, 5, 9, 7, 11, 13]\n",
      "1\n",
      "13\n",
      "49\n",
      "[1, 3, 5, 9, 7, 11, 13, 17, 19]\n",
      "[1, 3, 305, 5, 9, 7, 11, 13, 17, 19]\n",
      "[1, 3, 5, 9, 7, 11, 13, 17, 19]\n",
      "5\n",
      "False\n"
     ]
    }
   ],
   "source": [
    "l = [1, 3, 5, 9, 7, 11]\n",
    "\n",
    "print(len(l))  # Prints the number of elements in the list\n",
    "\n",
    "l.append(13)   # Appends 13 at the end of the list\n",
    "print(l)\n",
    "\n",
    "print(min(l)) # Returns minimum value in the list\n",
    "print(max(l)) # Returns maximum value in the list\n",
    "\n",
    "print(sum(l)) # Sums up elements of the list\n",
    "\n",
    "l = l + [17, 19] # Adds a list [17, 19] at the end of l\n",
    "print(l)\n",
    "\n",
    "l.insert(2, 305) # Insert at index 2, number 305\n",
    "print(l)\n",
    "\n",
    "del l[2] # Delete the element we inserted at index 2\n",
    "print(l)\n",
    "\n",
    "print(l.index(11)) # Return what index value 11 has\n",
    "\n",
    "print(305 in l) # Check if 305 is in the list"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "(lists_exercises)=\n",
    "## Exercises\n",
    "-------\n",
    "\n",
    "* **Multi-type lists** compared to other programming languages Python is very flexible when it comes to types of objects inside them. For example, we can have the following list:\n",
    "\n",
    "        l = [1,\"0\",True]\n",
    "\n",
    "    Try to transform the above list into the following one using list operations such as `del` and `append`:\n",
    "\n",
    "        l = [1,2,3]\n",
    "\n",
    "    Print the largest element of the list.\n"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "````{admonition} Answer\n",
    ":class: dropdown\n",
    "\n",
    "```python\n",
    "l = [1,\"0\",True]\n",
    "\n",
    "del l[2]\n",
    "del l[1]\n",
    "l.append(2)\n",
    "l.append(3)\n",
    "\n",
    "print(l)\n",
    "print(max(l))\n",
    "```\n",
    "\n",
    "````"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": []
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