Merge pull request #32 from pythonsd/part-4-suggestions

Merges suggested improvements for part 4

Author: willingc

part-4.ipynb

@@ -110,14 +110,14 @@
      "cell_type": "markdown",
      "metadata": {},
      "source": [
-      "Note how our list comprehension is written within the brackets: The for-loop statement is written at the end whereas the action inside of the for-loop is written first: n * n"
+      "Note how our list comprehension is written within the brackets: The list we're looping over (my_favorite_numbers) is written at the end whereas the action inside of the for-loop is written first: n * n"
      ]
     },
     {
      "cell_type": "markdown",
      "metadata": {},
      "source": [
-      "Let's revisit a problem we've already solved in Danny's lecture on list:\n",
+      "Let's revisit a problem we've already solved in Danny's lecture on lists:\n",
       "\n",
       "Pick every name from a list that begins with a vowel.\n",
       "\n",
@@ -321,14 +321,16 @@
      "cell_type": "markdown",
      "metadata": {},
      "source": [
-      "Let's translate each word and save them in the list called translated_words. We'll generate this list by using a list comprehension."
+      "Let's translate each word and save them in the list called translated_words. Let's start with an empty list and use a for loop to populate our list:"
      ]
     },
     {
      "cell_type": "code",
      "collapsed": false,
      "input": [
-      "translated_words = [print(words[spanish_word]) for spanish_word in sentence_words]"
+      "translated_words = []\n",
+      "for spanish_word in sentence_words:\n",
+      "    translated_words.append(words[spanish_word])"
      ],
      "language": "python",
      "metadata": {},
@@ -505,7 +507,13 @@
      "cell_type": "markdown",
      "metadata": {},
      "source": [
-      "**Extra Credit:** Try using a list comprehension in the translate function.\n",
+      "**Exercises:**\n",
+      "\n",
+      "1. Make a new py file and put that translate function in the file. Use the print function to print out some examples of using the function.\n",
+      "\n",
+      "2. Refactor the translate function to use a list comprehension.\n",
+      "\n",
+      "3. There are lots of ways to write that translate function.  Just for fun, see if you can write the whole translate function in one line.\n",
       "\n",
       "**Note:** Typing out the exercises for the next section, \"Sets\",  is optional. If your brain is melting, feel free to sit back, relax, and enjoy the rest of the lecture."
      ]