update slides for Day 3

lectures/Day_3.ipynb

@@ -82,7 +82,7 @@
     }
    },
    "source": [
-    "## Tuples (Q 1&2)\n",
+    "### Tuples (Q 1&2)\n",
     "\n",
     "__1. Which of the following variables are of the type tuple?__  \n",
     "`a = (1, 2, 3, 4)`  \n",
@@ -104,7 +104,7 @@
    "cell_type": "markdown",
    "metadata": {
     "slideshow": {
-     "slide_type": "fragment"
+     "slide_type": "slide"
     }
    },
    "source": [
@@ -129,7 +129,11 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "metadata": {},
+   "metadata": {
+    "slideshow": {
+     "slide_type": "fragment"
+    }
+   },
    "outputs": [],
    "source": [
     "myList[2]  = 4\n",
@@ -139,7 +143,11 @@
   {
    "cell_type": "code",
    "execution_count": null,
-   "metadata": {},
+   "metadata": {
+    "slideshow": {
+     "slide_type": "fragment"
+    }
+   },
    "outputs": [],
    "source": [
     "myTuple[2] = 4"
@@ -721,12 +729,12 @@
     }
    },
    "source": [
-    "## Day 3, Exercise 1 (~20 min)\n",
+    "## Day 3, Exercise 1 (~30 min)\n",
     "### Find the number of unique genres in the file `250.imdb`\n",
     "\n",
     "<img src=\"img/header_imdb.png\" alt=\"Drawing\" style=\"width: 1000px;\"/> \n",
     "\n",
-    "- Canvas -> Modules -> Day 3 -> IMDb exercise -> 1 \n",
+    "- Canvas -> Modules -> Day 3 -> IMDb exercise - day 3 -> 1 \n",
     "\n",
     "\n",
     "\n",
@@ -815,7 +823,7 @@
     "\n",
     "- A dictionary is an unordered, mutable collection of key-value pairs. \n",
     "- Dictionaries are mutable\n",
-    "- Each key in a dictionary must be unique and immutable, while the values associated with keys can be of any data type and can be duplicated\n",
+    "- Each key in a dictionary must be unique and immutable (the same as `set`), while the values associated with keys can be of any data type and can be duplicated\n",
     "\n",
     "<br>\n",
     "<img src=\"img/key_values.png\" alt=\"Drawing\" style=\"width: 1000px;\"/>  "
@@ -946,6 +954,13 @@
     "          'biography': 25}"
    ]
   },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
+  },
   {
    "cell_type": "markdown",
    "metadata": {
@@ -1003,7 +1018,7 @@
     "- #### (Extra) What is the average length of the movies (in hours and minutes) in each genre?\n",
     "\n",
     "\n",
-    "- Canvas -> Modules -> Day 3 -> IMDb exercise -> 2&3 \n",
+    "- Canvas -> Modules -> Day 3 -> IMDb exercise - day 3 -> 2&3 \n",
     "___\n",
     "#### Take a break after the exercise (~10 min)\n",
     "\n",
@@ -1116,7 +1131,6 @@
    "cell_type": "code",
    "execution_count": null,
    "metadata": {
-    "scrolled": true,
     "slideshow": {
      "slide_type": "skip"
     }
@@ -1286,7 +1300,34 @@
     "# Calculate the average duration of movies in the genre 'drama'\n",
     "genre = \"drama\"\n",
     "average = sum(genreDict[genre])/len(genreDict[genre])  # calculate average length per genre\n",
-    "hours   = int(average/3600)                                 # format seconds to hours\n",
+    "hours   = int(average/3600)                            # format seconds to hours\n",
+    "minutes = (average - (3600*hours))/60             # format seconds to minutes\n",
+    "reformattedTime = str(hours)+'h'+str(round(minutes))+'min'\n",
+    "print('The average length for movies in genre '+ genre +\\\n",
+    "      ' is '+ reformattedTime)"
+   ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "slideshow": {
+     "slide_type": "slide"
+    }
+   },
+   "source": [
+    "#### Now let convert this code into a function"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": [
+    "# Calculate the average duration of movies in the genre 'drama'\n",
+    "genre = \"drama\"\n",
+    "average = sum(genreDict[genre])/len(genreDict[genre])  # calculate average length per genre\n",
+    "hours   = int(average/3600)                            # format seconds to hours\n",
     "minutes = (average - (3600*hours))/60             # format seconds to minutes\n",
     "reformattedTime = str(hours)+'h'+str(round(minutes))+'min'\n",
     "print('The average length for movies in genre '+ genre +\\\n",
@@ -1753,7 +1794,7 @@
     }
    },
    "source": [
-    "### Try out `sys.argv`\n",
+    "### Try out `sys.argv` (~5 min)\n",
     "\n",
     "Python script is called `print_argv.py` and can be found in the downloads folder\n",
     "\n",
@@ -1765,6 +1806,39 @@
     "```"
    ]
   },
+  {
+   "cell_type": "markdown",
+   "metadata": {
+    "slideshow": {
+     "slide_type": "slide"
+    }
+   },
+   "source": [
+    "#### If you don't have the file print_argv.py, copy the following code and save it in a file called print_argv.py "
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {
+    "slideshow": {
+     "slide_type": "-"
+    }
+   },
+   "outputs": [],
+   "source": [
+    "#!/usr/bin/env python\n",
+    "import sys\n",
+    "\n",
+    "print(\"size of sys.argv = \", len(sys.argv))\n",
+    "print(\"program_name = \", sys.argv[0])\n",
+    "\n",
+    "counter = 1\n",
+    "while counter < len(sys.argv):\n",
+    "    print(\"arg\" + str(counter) + \" = \", sys.argv[counter])\n",
+    "    counter += 1"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {
@@ -2082,7 +2156,7 @@
     "### Day 3, Exercise 4 (~30 min)\n",
     "- #### Restructure and write the output to a new file\n",
     "\n",
-    "- Canvas -> Modules -> Day 3 -> IMDb exercise -> 4\n",
+    "- Canvas -> Modules -> Day 3 -> IMDb exercise - day 3 -> 4\n",
     "- Work in pairs\n",
     "\n",
     "#### PyQuiz 3.2 \n",