11-try_except.ipynb

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    "# Handling Exceptions\n",
    "* So far we have tested input with structures like if, and while\n",
    "* In addition Python has a structure meant to specifically trap errors\n",
    "* this allows programs to continue even after ancountering an error\n",
    "* Python hasa number of built-in Exception messages --> part of Exception class\n",
    "* You can also define your own exceptions"
   ]
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     "text": [
      "0.5\n"
     ]
    },
    {
     "ename": "TypeError",
     "evalue": "unsupported operand type(s) for /: 'str' and 'int'",
     "output_type": "error",
     "traceback": [
      "\u001b[1;31m---------------------------------------------------------------------------\u001b[0m",
      "\u001b[1;31mTypeError\u001b[0m                                 Traceback (most recent call last)",
      "\u001b[1;32m~\\AppData\\Local\\Temp/ipykernel_10104/67145840.py\u001b[0m in \u001b[0;36m<module>\u001b[1;34m\u001b[0m\n\u001b[0;32m      1\u001b[0m \u001b[0mvalues\u001b[0m \u001b[1;33m=\u001b[0m \u001b[1;33m[\u001b[0m\u001b[1;33m(\u001b[0m\u001b[1;36m1\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;36m2\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;33m(\u001b[0m\u001b[1;34m'5'\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;36m6\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;33m(\u001b[0m\u001b[1;36m5\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;36m4\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;33m(\u001b[0m\u001b[1;36m0\u001b[0m\u001b[1;33m,\u001b[0m \u001b[1;36m0\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m]\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0;32m      2\u001b[0m \u001b[1;32mfor\u001b[0m \u001b[0mval1\u001b[0m\u001b[1;33m,\u001b[0m \u001b[0mval2\u001b[0m \u001b[1;32min\u001b[0m \u001b[0mvalues\u001b[0m\u001b[1;33m:\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[1;32m----> 3\u001b[1;33m     \u001b[0mresult\u001b[0m \u001b[1;33m=\u001b[0m \u001b[0mval1\u001b[0m \u001b[1;33m/\u001b[0m \u001b[0mval2\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n\u001b[0m\u001b[0;32m      4\u001b[0m     \u001b[0mprint\u001b[0m\u001b[1;33m(\u001b[0m\u001b[0mresult\u001b[0m\u001b[1;33m)\u001b[0m\u001b[1;33m\u001b[0m\u001b[1;33m\u001b[0m\u001b[0m\n",
      "\u001b[1;31mTypeError\u001b[0m: unsupported operand type(s) for /: 'str' and 'int'"
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   "source": [
    "values = [(1, 2), ('5', 6), (5, 4), (0, 0)]\n",
    "for val1, val2 in values:\n",
    "    result = val1 / val2\n",
    "    print(result)"
   ]
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   "cell_type": "code",
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     "text": [
      "0.5\n",
      "That doesn't work\n",
      "1.25\n",
      "That doesn't work\n"
     ]
    }
   ],
   "source": [
    "values = [(1, 2), ('5', 6), (5, 4), (0, 0)]\n",
    "for val1, val2 in values:\n",
    "    try:\n",
    "        result = val1 / val2\n",
    "        print(result)\n",
    "    except:\n",
    "        print(\"That doesn't work\")\n"
   ]
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     "text": [
      "0.5\n",
      "That's a unsupported operand type(s) for /: 'str' and 'int'. Too bad!\n",
      "1.25\n",
      "That's a division by zero. Too bad!\n"
     ]
    }
   ],
   "source": [
    "# catch error and tell us what it is\n",
    "values = [(1, 2), ('5', 6), (5, 4), (0, 0)]\n",
    "for val1, val2 in values:\n",
    "    try:\n",
    "        result = val1 / val2\n",
    "        print(result)\n",
    "    except Exception as e:\n",
    "        print(f\"That's a {e}. Too bad!\")"
   ]
  },
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   "cell_type": "code",
   "execution_count": 18,
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     "text": [
      "0.5\n",
      "That's a unsupported operand type(s) for /: 'str' and 'int'. Too bad!\n",
      "1.25\n",
      "That's a division by zero. Too bad!\n"
     ]
    }
   ],
   "source": [
    "# this one only catches Type and Zero division errors, anything else will cause crash\n",
    "values = [(1, 2), ('5', 6), (5, 4), (0, 0)]\n",
    "for val1, val2 in values:\n",
    "    try:\n",
    "        result = val1 / val2\n",
    "        print(result)\n",
    "    except TypeError as e:\n",
    "        print(f\"That's a {e}. Too bad!\")\n",
    "    except ZeroDivisionError as e:\n",
    "        print(f\"That's a {e}. Too bad!\")"
   ]
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    "values = [(1, 2), ('5', 6), (5, 4), (0, 0)]\n",
    "for val1, val2 in values:\n",
    "    try:\n",
    "        result = val1 / val2\n",
    "        print(result)\n",
    "    except TypeError as e:\n",
    "        print(f\"That's a {e}. Too bad!\")\n",
    "    except ZeroDivisionError as e:\n",
    "        print(f\"That's a {e}. Too bad!\")\n",
    "    except Exception as e:\n",
    "        print(\"This is how I handle everything else\")\n",
    "    "
   ]
  },
  {
   "cell_type": "code",
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   "source": [
    "values = [(1, 2), ('5', 6), (5, 4), (0, 0)]\n",
    "for val1, val2 in values:\n",
    "    try:\n",
    "        result = val1 / val2\n",
    "        \n",
    "    except TypeError as e:\n",
    "        print(f\"That's a {e}. Too bad!\")\n",
    "    except ZeroDivisionError as e:\n",
    "        print(f\"That's a {e}. Too bad!\")\n",
    "    except Exception as e:\n",
    "        print(\"This is how I handle everything else\")\n",
    "    else:\n",
    "        print(result)\n",
    "    finally:\n",
    "        print(\"this happens no matter what\")"
   ]
  },
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