11-Python Generators/03-Iterators and Generators Homework - Solution.ipynb

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   "source": [
    "# Iterators and Generators Homework - Solution\n",
    "\n",
    "### Problem 1\n",
    "\n",
    "Create a generator that generates the squares of numbers up to some number N."
   ]
  },
  {
   "cell_type": "code",
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   "metadata": {},
   "outputs": [],
   "source": [
    "def gensquares(N):\n",
    "    for i in range(N):\n",
    "        yield i**2"
   ]
  },
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   "cell_type": "code",
   "execution_count": 2,
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     "text": [
      "0\n",
      "1\n",
      "4\n",
      "9\n",
      "16\n",
      "25\n",
      "36\n",
      "49\n",
      "64\n",
      "81\n"
     ]
    }
   ],
   "source": [
    "for x in gensquares(10):\n",
    "    print(x)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Problem 2\n",
    "\n",
    "Create a generator that yields \"n\" random numbers between a low and high number (that are inputs).<br>Note: Use the random library. For example:"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
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       "3"
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     "execution_count": 3,
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   "source": [
    "import random\n",
    "\n",
    "random.randint(1,10)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [],
   "source": [
    "def rand_num(low,high,n):\n",
    "    \n",
    "    for i in range(n):\n",
    "        yield random.randint(low, high)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
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     "name": "stdout",
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     "text": [
      "3\n",
      "9\n",
      "6\n",
      "10\n",
      "8\n",
      "4\n",
      "5\n",
      "5\n",
      "5\n",
      "3\n",
      "5\n",
      "8\n"
     ]
    }
   ],
   "source": [
    "for num in rand_num(1,10,12):\n",
    "    print(num)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Problem 3\n",
    "\n",
    "Use the iter() function to convert the string below into an iterator:\n"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "h\n"
     ]
    }
   ],
   "source": [
    "s = 'hello'\n",
    "\n",
    "s = iter(s)\n",
    "\n",
    "print(next(s))"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Problem 4\n",
    "Explain a use case for a generator using a yield statement where you would not want to use a normal function with a return statement.\n",
    "\n",
    "**If the output has the potential of taking up a large amount of memory and you only intend to iterate through it, you would want to use a generator. (Multiple answers are acceptable here!)**"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "### Extra Credit!\n",
    "Can you explain what *gencomp* is in the code below? (Note: We never covered this in lecture!)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 7,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "4\n",
      "5\n"
     ]
    }
   ],
   "source": [
    "my_list = [1,2,3,4,5]\n",
    "\n",
    "gencomp = (item for item in my_list if item > 3)\n",
    "\n",
    "for item in gencomp:\n",
    "    print(item)"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "Hint: Google *generator comprehension*!\n",
    "\n",
    "# Great Job!"
   ]
  }
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