maps_and_lists.ipynb

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  {
   "cell_type": "markdown",
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   "metadata": {},
   "source": [
    "## Python maps and lists"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "id": "british-forwarding",
   "metadata": {},
   "outputs": [
    {
     "output_type": "stream",
     "name": "stdout",
     "text": [
      "abc\n[1, 4, 9]\n[4]\n"
     ]
    }
   ],
   "source": [
    "# lambda\n",
    "test = lambda x:print(x)\n",
    "test('abc')\n",
    "\n",
    "# list comprehensions (map)\n",
    "list1 = [item ** 2 for item in [1,2,3]]\n",
    "\n",
    "# list comprehensions (filter)\n",
    "list2 = [item ** 2 for item in [1,2,3] if item % 2 == 0]\n",
    "\n",
    "print(list1)\n",
    "print(list2)"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "selective-delay",
   "metadata": {},
   "source": [
    "### Map"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "id": "protecting-pasta",
   "metadata": {},
   "outputs": [
    {
     "output_type": "execute_result",
     "data": {
      "text/plain": [
       "[2, 3, 4]"
      ]
     },
     "metadata": {},
     "execution_count": 2
    }
   ],
   "source": [
    "plus_one = lambda n: n + 1 ; l = [1, 2, 3]\n",
    "\n",
    "list(map(plus_one, l))"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "acquired-display",
   "metadata": {},
   "source": [
    "### Filter"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "id": "artistic-divorce",
   "metadata": {},
   "outputs": [
    {
     "output_type": "execute_result",
     "data": {
      "text/plain": [
       "[2, 4]"
      ]
     },
     "metadata": {},
     "execution_count": 3
    }
   ],
   "source": [
    "is_even = lambda n: n % 2 == 0 ; l = [1,2,3,4]\n",
    "\n",
    "list(filter(is_even,l))"
   ]
  },
  {
   "cell_type": "markdown",
   "id": "aboriginal-terrain",
   "metadata": {},
   "source": [
    "### Reduce"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "id": "rising-screen",
   "metadata": {},
   "outputs": [
    {
     "output_type": "execute_result",
     "data": {
      "text/plain": [
       "6"
      ]
     },
     "metadata": {},
     "execution_count": 4
    }
   ],
   "source": [
    "from functools import reduce\n",
    "\n",
    "l = [1,2,3]\n",
    "\n",
    "reduce((lambda a, b: a + b), l)\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "cultural-faculty",
   "metadata": {},
   "outputs": [],
   "source": []
  }
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