python-intro/exercises/ex09_lists.ipynb

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   "source": [
    "# Exercise 9: Lists"
   ]
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   "source": [
    "## Aim: Introduce lists and their methods."
   ]
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   "source": [
    "### Issues covered:\n",
    "- Creating a list\n",
    "- Indexing and slicing lists\n",
    "- Using methods on lists"
   ]
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   "source": [
    "## 1. Creating a basic list "
   ]
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   "source": [
    "Create a list containing the values \"hello\", \"my\", \"name\", and \"is\" and print it."
   ]
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   "source": [
    "## 2. Indexing and slicing lists"
   ]
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   "source": [
    "Use list indexing to select the second item in the list."
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    "Use list indexing to select the second to last item in the list."
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   "source": [
    "Use list slicing to select the whole list."
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   "source": [
    "## 3. Modifying lists and using methods"
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   "source": [
    "Add your name to the end of the list and print it."
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   "source": [
    "Try running the cell above multiple times and see what happens to your answer."
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   "source": [
    "Remove the effects of running the cell multiple times by deleting some words. "
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    "Replace the word \"name\" with \"age\" and replace your name with your age (or any number you like). Your output should look something like this:\n",
    "```\n",
    "['hello', 'my', 'age', 'is', 100]\n",
    "```"
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    "## 4. Let's create a list from a range and modify it"
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    "Create a list `y` with values from 1 to 10 using the `range()` function."
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    "Replace the first item in the list with the value `10`. "
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   "source": [
    "Append the number `11` to the list."
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   "source": [
    "Add another list `[12, 13, 14]` to the list using the `extend` method."
   ]
  },
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   "source": [
    "## 5. Using list methods on character strings."
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    "Use `list()` to create a list with the characters 'software carpentry'."
   ]
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    "How many characters are in this string? (i.e. what is the length of the list?)"
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   "source": [
    "That's quite a lot of characters. Turn it back into a string again using `.join()`."
   ]
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   "source": [
    "Use list slicing to print only the first word (first 8 characters) from the string."
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   "source": [
    "Print every other letter from the string - you should get `sfwr apnr`."
   ]
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    "Print the string backwards."
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   "source": [
    "_Hint: Slicing can be written as `[low:high:stride]` and to go backwards you would need a stride of -1._"
   ]
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   "source": [
    "First try using: \n",
    "```\n",
    "a = list('hello everybody')\n",
    "b = sorted(a)\n",
    "print(a)\n",
    "```\n",
    "Then try using:\n",
    "```\n",
    "a = list('hello everybody')\n",
    "b = a.sort()\n",
    "print(a)\n",
    "```\n",
    "Why are they different?"
   ]
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