610_Errors_and_Exceptions.ipynb

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    "# Errors and Exceptions\n",
    "\n",
    "Errors will always happen when you're coding, and Python is not any different. In fact, when your Python program runs into an error it will often die and cause your program to crash. \n",
    "\n",
    "By catching errors you can gracefully handle an error. \n",
    "\n",
    "Errors come in many different sizes. We can catch all errors or specific errors. \n",
    "\n",
    "And whenever an error is created, that's called \"raising an error\" and \"catching an error\"."
   ]
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   "cell_type": "code",
   "execution_count": 2,
   "metadata": {},
   "outputs": [
    {
     "ename": "ZeroDivisionError",
     "evalue": "division by zero",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mZeroDivisionError\u001b[0m                         Traceback (most recent call last)",
      "\u001b[0;32m<ipython-input-2-41f182f93c20>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0;36m1\u001b[0m\u001b[0;34m/\u001b[0m\u001b[0;36m0\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m\u001b[1;32m      2\u001b[0m \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0;34m\"HELLLOOOOO\"\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n",
      "\u001b[0;31mZeroDivisionError\u001b[0m: division by zero"
     ]
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   "source": [
    "1/0\n",
    "print(\"HELLLOOOOO\")"
   ]
  },
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   "cell_type": "markdown",
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   "source": [
    "> **Note:** This is a **ZeroDivisionError**. Programs can't typically figure out how to divide by zero, so it throws us the ZeroDivisionError, and we can gracefully handle this later. "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {},
   "outputs": [],
   "source": [
    "d = {'name': 'kalob'}"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {},
   "outputs": [
    {
     "ename": "KeyError",
     "evalue": "'hobby'",
     "output_type": "error",
     "traceback": [
      "\u001b[0;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[0;31mKeyError\u001b[0m                                  Traceback (most recent call last)",
      "\u001b[0;32m<ipython-input-4-f2b0ad0ce0d4>\u001b[0m in \u001b[0;36m<module>\u001b[0;34m\u001b[0m\n\u001b[0;32m----> 1\u001b[0;31m \u001b[0mprint\u001b[0m\u001b[0;34m(\u001b[0m\u001b[0md\u001b[0m\u001b[0;34m[\u001b[0m\u001b[0;34m'hobby'\u001b[0m\u001b[0;34m]\u001b[0m\u001b[0;34m)\u001b[0m\u001b[0;34m\u001b[0m\u001b[0;34m\u001b[0m\u001b[0m\n\u001b[0m",
      "\u001b[0;31mKeyError\u001b[0m: 'hobby'"
     ]
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   ],
   "source": [
    "print(d['hobby'])"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "> **Note:** The `hobby` key didn't exist in the dictionary `d`. So Python raised a **KeyError**. Now that we know what the error is, we can gracefully handle it."
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {},
   "outputs": [],
   "source": [
    "# try to execute the code \n",
    "# except try to handle the errror\n",
    "# finally will always run no matter what "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 8,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The total is  N/A\n"
     ]
    }
   ],
   "source": [
    "try:\n",
    "    total = 10/0\n",
    "except ZeroDivisionError:\n",
    "    total = 'N/A'\n",
    "finally:\n",
    "    print(\"The total is \", total)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 11,
   "metadata": {},
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "Enter a number: 123\n",
      "There was an error\n",
      "The program can continue without problems\n"
     ]
    }
   ],
   "source": [
    "number1 = 50\n",
    "number2 = input(\"Enter a number: \")\n",
    "try:\n",
    "    total = number1 + number2 \n",
    "    print(total)\n",
    "except:\n",
    "    print(\"There was an error\")\n",
    "print(\"The program can continue without problems\")"
   ]
  }
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