Update docs & Projects - the gradebook.

Codecademy.md

@@ -111,7 +111,7 @@ False = int(0)
 
 Force treating as a string: str(7)
 Force treating as an integer: int("7")
-Froce treating as a float: float(7)
+Force treating as a float: float(7)
 
 ## Check Datatypes
 
@@ -263,6 +263,106 @@ You can also do this with multiple arguments:
 x_squared, y_squared = square_point(1, 3)
 ```
 
+# Lists
+
+You can put either strings, integers or other lists in a list, probably other things too.
+
+`heights = [['Jenny', 61], ['Alexus', 70], ['Sam', 67], ['Grace', 64]]`
+
+Use zip to combine elements from two lists: `zip(names, dogs_names)` would match dogs and their owners.
+
+But don't forget to turn it into a list before printing `print(list(zipvar))`
+
+You can append values to lists like this:
+
+```
+orders = ['daisies', 'periwinkle']
+orders.append('tulips')
+```
+
+## Ranges
+
+You can get a range of numbers using `range()`
+
+It will give you all numbers under the number you input. For example, `range(8)` would give you 0-7, `range(1, 8)` would give you 1-7, and `range(1, 8, 2)` would give you 1,3,5,7 (2 is the interval) Use `print(list(var))` when printing.
+
+## length
+
+Grab length with `len(list)`
+
+# Selecting List elements
+
+  Use: `listname[indexnumber]`
+
+  The index starts at 0. Grab the last in an index using `list[-1]`
+
+## Giving values to list elements
+
+  `lst[index] = indexlst`
+
+## Cutting the middle of a list (ex3, functions + lists, ch.4)
+
+  ```
+def remove_middle(lst, start, end):
+  end = end + 1
+  return lst[:start] + lst[end:]
+
+print(remove_middle([4, 8, 15, 16, 23, 42], 1, 3))
+```
+This prints `[4, 23, 42]` removing the index 1-3.
+
+# If something occurs more than N times, return True
+```
+def more_than_n(lst, item, n):
+if lst.count(item) > n:
+  return True
+else:
+  return False
+
+  print(more_than_n([2, 4, 6, 2, 3, 2, 1, 2], 2, 3))
+```
+
+### Sublists
+
+Grab a subset of a list using `sublist = letters[1:6]` This would give you index **1-5**.
+
+You can also do `[:5]` for all up to index 4, and `[5:]` for all after index 5. And, you can do `[-3:]` for the last 3 in an index.
+
+## Counting frequency of elements in a list.
+
+  `var.count('stringtofind')`
+
+## Sorting strings alphabetically
+
+  ```
+  var.sort()
+  print(var)
+  ```
+
+or use
+
+```
+sortedvar = sorted(var)
+```
+
+to produce a new list with sorted contents without changing the original variable.
+
+## Sorting strings based on an element in a sublist
+
+  Replace 1 with the index you want to sort by.
+
+  `pizzas.sort(key=lambda x: x[1])``
+
+# Catch Errors
+
+  ```
+  try:
+    command_may_cause_error
+  except NameOfError:
+    print("Nice little message to user.")
+  ```
+
+
 # Fun Projects
 
 Design a shop using Ex7 and Ex9 as a frame:

Codecadmey Projects/lens-pizza.py

@@ -0,0 +1,14 @@
+toppings = ['pepperoni', 'pineapple', 'cheese', 'sausage', 'olives', 'anchovies', 'mushrooms']
+prices = [2, 6, 1, 3, 2, 7, 2]
+num_pizzas = len(toppings)
+print("We sell " + str(num_pizzas) + " kinds of pizza!")
+pizzas = list(zip(toppings, prices))
+
+pizzas.sort(key=lambda x: x[1])
+cheapest_pizza = pizzas[0]
+priciest_pizza = pizzas[-1]
+three_cheapest = pizzas[0:3]
+print(pizzas)
+print(three_cheapest)
+num_two_dollar_slices = prices.count(2)
+print(num_two_dollar_slices)