List Compreshension.ipynb

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   "cell_type": "code",
   "execution_count": 1,
   "metadata": {},
   "outputs": [],
   "source": [
    "def sq(x):\n",
    "    return x**2"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[1, 4, 9, 16, 25]"
      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
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   ],
   "source": [
    "list(map(lambda x : x**2, [1, 2, 3, 4, 5]))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[1, 4, 9, 16, 25]"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "ls = []\n",
    "for i in [1, 2, 3, 4, 5]:\n",
    "    ls.append(i**2)\n",
    "ls\n",
    "    "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[1, 4, 9, 16, 25]"
      ]
     },
     "execution_count": 5,
     "metadata": {},
     "output_type": "execute_result"
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   ],
   "source": [
    "# Syntax: new_list = [expression for_loop_one or more_loop]\n",
    "\n",
    "# Map with lambda\n",
    "\n",
    "[i**2 for i in [1, 2, 3, 4, 5]]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [],
   "source": [
    "def ever_only(x):\n",
    "    if x%2==0:\n",
    "        return x"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {},
   "outputs": [
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      "text/plain": [
       "[2, 4]"
      ]
     },
     "execution_count": 19,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "list(filter(lambda x :(x%2==0), [1,2,3,4]))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 21,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[2, 4]"
      ]
     },
     "execution_count": 21,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "[x for x in [1,2,3,4] if x%2==0]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 22,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[32.0, 50.0, 68.36, 100.76]"
      ]
     },
     "execution_count": 22,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "lst = [0, 10, 20.2, 38.2]\n",
    "\n",
    "[(9/5)*c+32 for c in lst]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 26,
   "metadata": {},
   "outputs": [],
   "source": [
    "ls1 = [10, 20, 30, 40, 50]\n",
    "ls2 = [30, 40, 50, 60, 70]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 29,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[30, 40, 50]"
      ]
     },
     "execution_count": 29,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "lst = []\n",
    "for i in ls1:\n",
    "    for j in ls2:\n",
    "        if i == j:\n",
    "            lst.append(i)\n",
    "lst\n",
    "    "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 31,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "[30, 40, 50]"
      ]
     },
     "execution_count": 31,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "[i for i in ls1 for j in ls2 if i==j]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 35,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['g', 'o', 'p', 'i']"
      ]
     },
     "execution_count": 35,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "list('gopi')"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 37,
   "metadata": {},
   "outputs": [
    {
     "data": {
      "text/plain": [
       "['G', 'O', 'P', 'I']"
      ]
     },
     "execution_count": 37,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "[x.upper() for x in 'gopi']"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 40,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "0 aaa\n",
      "1 bbb\n",
      "2 ccc\n",
      "index number of ccc is:  2\n",
      "3 ddd\n",
      "4 eee\n"
     ]
    }
   ],
   "source": [
    "# enumerates\n",
    "lst = ['aaa', 'bbb', 'ccc', 'ddd', 'eee']\n",
    "j = 0\n",
    "for i in lst:\n",
    "    print(j, i)\n",
    "    if (i =='ccc'):\n",
    "        print('index number of ccc is: ', j)\n",
    "    j=j+1\n",
    "    \n",
    "    "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 46,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "2\n"
     ]
    }
   ],
   "source": [
    "lst = ['aaa', 'bbb', 'ccc', 'ddd', 'eee']\n",
    "for i, j in enumerate(lst):\n",
    "    if(j == \"ccc\"):\n",
    "         print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 48,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "(3, 'March')\n",
      "(4, 'April')\n",
      "(5, 'May')\n",
      "(6, 'June')\n"
     ]
    }
   ],
   "source": [
    "months = ['March', 'April', 'May', 'June']\n",
    "\n",
    "for i in enumerate(months, start=3):\n",
    "    print(i)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {},
   "outputs": [],
   "source": [
    "# Zip, unzip"
   ]
  }
 ],
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