tut02.ipynb

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   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Lists might contain items of the same or different data types\n",
    "primes = [2,3,5,7,11,13]\n",
    "mixed_basket = [1,['apples',3,3.45],2,['oranges',4.05]]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "4"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Size of a list\n",
    "len(mixed_basket)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[13, 11, 7, 5, 3, 2]"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Indexing, Slicing, Steps\n",
    "primes[::-1]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "[9, 25, 49, 121, 169]\n"
     ]
    }
   ],
   "source": [
    "# List Comprehension\n",
    "square = []\n",
    "for x in primes:\n",
    "    square.append(x**2)\n",
    "    \n",
    "square2 = [x**2 for x in primes if x % 2 == 1]\n",
    "\n",
    "print(square2)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Python built-in functions and methods (Read the docs)\n",
    "numbers = [2, 4, -23, 2, 95, 21]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Sort\n",
    "# sorted(numbers, reverse=True)\n",
    "# numbers.sort()\n",
    "# print(numbers)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[21, 95, 2, -23, 4, 2]"
      ]
     },
     "execution_count": 7,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Reverse\n",
    "list(reversed(numbers))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "3.0"
      ]
     },
     "execution_count": 8,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Find median\n",
    "import statistics\n",
    "statistics.median(numbers)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 9,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Dictionaries are indexed by keys\n",
    "phone = {'sam': 97896000, 'john':95842384, 'tom':97268907}"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 10,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'sam': 97896000, 'john': 12345, 'tom': 97268907, 'steve': 6789}\n"
     ]
    }
   ],
   "source": [
    "# Add/Update an item\n",
    "phone['john'] = 12345\n",
    "phone['steve'] = 6789\n",
    "print(phone)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "{'john': 12345, 'tom': 97268907, 'steve': 6789}\n"
     ]
    }
   ],
   "source": [
    "# Delete an item\n",
    "del(phone['sam'])\n",
    "print(phone)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 12,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "97268907"
      ]
     },
     "execution_count": 12,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "# Get value of a key\n",
    "phone['tom']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 13,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Get key of a value"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "john 12345\n",
      "tom 97268907\n",
      "steve 6789\n"
     ]
    }
   ],
   "source": [
    "# Loop through dictionary\n",
    "for k,v in phone.items():\n",
    "    print(k,v)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "steven phone not found\n"
     ]
    }
   ],
   "source": [
    "# Check if a key in dictionary\n",
    "name = 'steven'\n",
    "if name in phone:\n",
    "    print(phone[name])\n",
    "else:\n",
    "    print(f'{name} phone not found')"
   ]
  }
 ],
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