Tutorial 20-List Comprehension.ipynb

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   "source": [
    "## Python List Comprehension"
   ]
  },
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    {
     "data": {
      "text/plain": [
       "list"
      ]
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     "execution_count": 2,
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   "source": [
    "type([1,2,3,4,5,5])"
   ]
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     "name": "stdout",
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     "text": [
      "[0, 1, 2, 3, 4, 5, 6, 7]\n"
     ]
    }
   ],
   "source": [
    "lst=[]\n",
    "for i in range(0,8):\n",
    "    lst.append(i)\n",
    "    \n",
    "print(lst)\n",
    "    "
   ]
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     "text": [
      "[1, 4, 9, 16, 25, 36]\n"
     ]
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   "source": [
    "lst=[1,2,3,4,5,6]\n",
    "lst2=[]\n",
    "for i in lst:\n",
    "    lst2.append(i**2)\n",
    "    \n",
    "print(lst2)"
   ]
  },
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     "text": [
      "[1, 4, 9, 16, 25]\n"
     ]
    }
   ],
   "source": [
    "numbers=[1,2,3,4,5]\n",
    "squard_numbers=[i**2 for i in numbers]\n",
    "print(squard_numbers)"
   ]
  },
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   "execution_count": 8,
   "id": "5a9c351b-d8e4-4e34-ab70-edbc962ab9c5",
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   "outputs": [
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     "text": [
      "[2, 4, 6, 8, 10]\n"
     ]
    }
   ],
   "source": [
    "## Filtering even numbers from a list:\n",
    "numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]\n",
    "even_number=[n for n in numbers if n%2==0]\n",
    "print(even_number)"
   ]
  },
  {
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   "execution_count": 9,
   "id": "de2a1c7c-303a-4d7a-899f-70b672536646",
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   "source": [
    "##Flattening a list of lists: 2 for loops\n",
    "lists = [[1, 2, 3], [4, 5, 6], [7, 8, 9]]\n",
    "flattend_list=[item for sublist in lists for item in sublist ]"
   ]
  },
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   "execution_count": 10,
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   "outputs": [
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     "data": {
      "text/plain": [
       "[1, 2, 3, 4, 5, 6, 7, 8, 9]"
      ]
     },
     "execution_count": 10,
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   ],
   "source": [
    "flattend_list"
   ]
  },
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   "execution_count": 11,
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     "text": [
      "['a', 'b', 'c', 'd']\n"
     ]
    }
   ],
   "source": [
    "# Generating a list of the first letters of words in a list:\n",
    "words = ['apple', 'banana', 'cherry', 'date']\n",
    "first_letters=[word[0] for word in words]\n",
    "print(first_letters)"
   ]
  },
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   "cell_type": "code",
   "execution_count": 12,
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   "outputs": [
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     "data": {
      "text/plain": [
       "[4, 16, 36, 64, 100]"
      ]
     },
     "execution_count": 12,
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    }
   ],
   "source": [
    "## Generating a list of the squares of even numbers\n",
    "numbers = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10]\n",
    "[n**2 for n in numbers if n%2==0]"
   ]
  },
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   "outputs": [
    {
     "data": {
      "text/plain": [
       "[1, 2, 3, 4, 5]"
      ]
     },
     "execution_count": 13,
     "metadata": {},
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    }
   ],
   "source": [
    "## Converting a list of strings to a list of integers\n",
    "strings = ['1', '2', '3', '4', '5']\n",
    "[int(s) for s in strings]"
   ]
  },
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   "cell_type": "code",
   "execution_count": 14,
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   "outputs": [
    {
     "data": {
      "text/plain": [
       "[1,\n",
       " 2,\n",
       " 3,\n",
       " 5,\n",
       " 8,\n",
       " 13,\n",
       " 21,\n",
       " 34,\n",
       " 55,\n",
       " 89,\n",
       " 144,\n",
       " 233,\n",
       " 377,\n",
       " 610,\n",
       " 987,\n",
       " 1597,\n",
       " 2584,\n",
       " 4181,\n",
       " 6765]"
      ]
     },
     "execution_count": 14,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "## Generating a list of the Fibonacci sequence using a list comprehension\n",
    "fib = [0, 1, 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610, 987, 1597, 2584, 4181, 6765]\n",
    "\n",
    "[fib[i-1]+ fib[i-2] for i in range(2,len(fib))]"
   ]
  },
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   "execution_count": 15,
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    {
     "data": {
      "text/plain": [
       "[1, 2, 3, 4, 6, 9, 12, 18, 36]"
      ]
     },
     "execution_count": 15,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "##Generating a list of all the divisors of a number:\n",
    "\n",
    "number =36\n",
    "[i for i in range(1,number+1) if number%i==0]"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "id": "245a02a9-77db-472a-9c51-634e08c04f2e",
   "metadata": {},
   "outputs": [],
   "source": [
    "## Generating a list of all the prime numbers less than a given number:"
   ]
  },
  {
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   "execution_count": null,
   "id": "7354d100-6b94-4fc0-8a8d-310d0872701c",
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