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    "# Exercise solutions"
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    "## Chapter 2\n",
    "\n",
    "### Exercise 2.1\n",
    "\n",
    "```python\n",
    "# Define main variables\n",
    "ice_cream_rating = 9\n",
    "sleep_rating = 8\n",
    "name = \"Dave\"\n",
    "\n",
    "# Calculate happiness\n",
    "happiness_rating = (ice_cream_rating + sleep_rating) / 2\n",
    "\n",
    "# Print variable types\n",
    "print(type(ice_cream_rating))\n",
    "print(type(sleep_rating))\n",
    "print(type(name))\n",
    "print(type(happiness_rating))\n",
    "\n",
    "# Print formatted text\n",
    "print(\"My name is\", name, \"and I give eating ice cream a score of\", ice_cream_rating, \"out of 10!\")\n",
    "print(\"My sleeping enjoyment rating is\", sleep_rating, \"/ 10!\")\n",
    "print(\"Based on the factors above, my happiness rating is\", happiness_rating, \"or\", happiness_rating * 10, \"%!\")\n",
    "```\n",
    "\n",
    "### Exercise 2.2\n",
    "\n",
    "```python\n",
    "# Define left table lists\n",
    "station_names = [\"lighthouse\", \"Harmaja\", \"Suomenlinna aaltopoiju\", \"Kumpula\", \"Kaisaniemi\"]\n",
    "station_start_years = [2003, 1989, 2016, 2005, 1844]\n",
    "\n",
    "# Add values from table on the right\n",
    "station_names.append(\"Malmi airfield\")\n",
    "station_names.append(\"Vuosaari harbour\")\n",
    "station_names.append(\"Kaivopuisto\")\n",
    "station_start_years.append(1937)\n",
    "station_start_years.append(2012)\n",
    "station_start_years.append(1904)\n",
    "\n",
    "# Sort lists as directed\n",
    "station_names.sort()\n",
    "station_start_years.sort()\n",
    "station_start_years.reverse()\n",
    "\n",
    "# Problem: List values are no longer correctly linked for same index value\n",
    "```\n",
    "\n",
    "### Exercise 2.3\n",
    "\n",
    "```python\n",
    "# Create lists of months and temperatures\n",
    "months = ['January', 'February', 'March', 'April', 'May', 'June', 'July', 'August', \\\n",
    "          'September', 'October', 'November', 'December']\n",
    "average_temp = [-3.5, -4.5, -1.0, 4.0, 10.0, 15.0, 18.0, 16.0, 11.5, 6.0, 2.0, -1.5]\n",
    "\n",
    "# Select month and create print statement output\n",
    "selected_month_index = 6\n",
    "print_statement = f\"The average temperature in Helsinki in {months[selected_month_index]} is {average_temp[selected_month_index]}\"\n",
    "\n",
    "# Alternative print statement format\n",
    "print_statement = 'The average temperature in Helsinki in ' + str(months[selected_month_index]) + ' is ' + str(average_temp[selected_month_index])\n",
    "```\n",
    "\n",
    "### Exercise 2.4\n",
    "\n",
    "```python\n",
    "# Create variable with file base name\n",
    "basename = \"Station\"\n",
    "\n",
    "# Create empty list for filenames\n",
    "filenames = []\n",
    "\n",
    "# Use for loop to populate list of filenames\n",
    "for i in range(21):\n",
    "    station = basename + \"_\" + str(i) + \".txt\"\n",
    "    filenames.append(station)\n",
    "```\n",
    "\n",
    "### Exercise 2.5\n",
    "\n",
    "```python\n",
    "# Store list of temperatures in memory\n",
    "temperatures = [-5.4, 1.0, -1.3, -4.8, 3.9, 0.1, -4.4, 4.0, -2.2, -3.9, 4.4,\n",
    "                -2.5, -4.6, 5.1, 2.1, -2.4, 1.9, -3.3, -4.8, 1.0, -0.8, -2.8,\n",
    "                -0.1, -4.7, -5.6, 2.6, -2.7, -4.6, 3.4, -0.4, -0.9, 3.1, 2.4,\n",
    "                1.6, 4.2, 3.5, 2.6, 3.1, 2.2, 1.8, 3.3, 1.6, 1.5, 4.7, 4.0,\n",
    "                3.6, 4.9, 4.8, 5.3, 5.6, 4.1, 3.7, 7.6, 6.9, 5.1, 6.4, 3.8,\n",
    "                4.0, 8.6, 4.1, 1.4, 8.9, 3.0, 1.6, 8.5, 4.7, 6.6, 8.1, 4.5,\n",
    "                4.8, 11.3, 4.7, 5.2, 11.5, 6.2, 2.9, 4.3, 2.8, 2.8, 6.3, 2.6,\n",
    "                -0.0, 7.3, 3.4, 4.7, 9.3, 6.4, 5.4, 7.6, 5.2]\n",
    "\n",
    "# Create empty lists for classification\n",
    "cold = []\n",
    "slippery = []\n",
    "comfortable = []\n",
    "warm = []\n",
    "\n",
    "# Use for loop and conditional statements to populate category lists\n",
    "for temp in temperatures:\n",
    "    if temp < -2:\n",
    "        cold.append(temp)\n",
    "    elif temp >= -2 and temp < 2:\n",
    "        slippery.append(temp)\n",
    "    elif temp >= 2 and temp < 15:\n",
    "        comfortable.append(temp)\n",
    "    elif temp >= 15:\n",
    "        warm.append(temp)\n",
    "\n",
    "# Alternative solution\n",
    "# Note: Because of the test order \"greater than or equal to\" tests are not required\n",
    "for temp in temperatures:\n",
    "    if temp < -2:\n",
    "        cold.append(temp)\n",
    "    elif temp < 2:\n",
    "        slippery.append(temp)\n",
    "    elif temp < 15:\n",
    "        comfortable.append(temp)\n",
    "    elif temp >= 15:\n",
    "        warm.append(temp)\n",
    "\n",
    "# Print out number of times it was cold, comfortable, or warm\n",
    "print(f\"It was cold {len(cold)} times in Helsinki in April 2013.\")\n",
    "print(f\"It was cold {len(comfortable)} times in Helsinki in April 2013.\")\n",
    "print(f\"It was cold {len(warm)} times in Helsinki in April 2013.\")\n",
    "```\n",
    "\n",
    "### Exercise 2.6\n",
    "\n",
    "```python\n",
    "# Create temperature conversion function\n",
    "def fahr_to_celsius(temp_fahrenheit):\n",
    "    \"\"\"Converts Fahrenheit temperature into Celsius.\"\"\"\n",
    "    converted_temp = (temp_fahrenheit - 32) / 1.8\n",
    "    \n",
    "    return converted_temp\n",
    "\n",
    "# Make a list of temperatures to convert and loop over them to convert\n",
    "fahr_temps = [32, 68, 91, -17]\n",
    "for fahr_temp in fahr_temps:\n",
    "    print(f\"{fahr_temp} °F is equal to {fahr_to_celsius(fahr_temp):.1f} °C.\")\n",
    "```\n",
    "\n",
    "### Exercise 2.7\n",
    "\n",
    "```python\n",
    "def temp_classifier(temp_celsius):\n",
    "    \"\"\"\n",
    "    Classifies temperatures into 4 different classes according following criteria:\n",
    "    \n",
    "    - Less than -2 degrees: returns 0\n",
    "    - Less than +2 degrees and greater than or equal to -2 degrees: returns 1\n",
    "    - Less than +15 degrees and greater than or equal to +2 degrees: returns 2\n",
    "    - Greater than or equal to 15 degrees: returns 3        \n",
    "    \"\"\"\n",
    "    if temp_celsius < -2:\n",
    "        return 0\n",
    "    elif temp_celsius >= -2 and temp_celsius < 2:\n",
    "        return 1\n",
    "    elif temp_celsius >= 2 and temp_celsius < 15:\n",
    "        return 2\n",
    "    else:\n",
    "        return 3\n",
    "\n",
    "# Create list of temperatures to classify and classify them\n",
    "celsius_temps = [17, 2, 1.9, -2]\n",
    "for celsius_temp in celsius_temps:\n",
    "    print(f\"The temperature {celsius_temp} °C is in category {temp_classifier(celsius_temp)}.\")\n",
    "```"
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