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| public:t-vien-07-1:lab_1_materials [2008/01/09 16:56] – hannes | public:t-vien-07-1:lab_1_materials [2024/04/29 13:33] (current) – external edit 127.0.0.1 |
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| ===== In-Class Excercises ===== | ===== In-Class Excercises ===== |
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| print j | print j |
| </code> | </code> |
| - Add the class **''Tool''** to your program. This class represents a useful object that is made from some particular material. | - Add the class **''Tool''** to your program. This class represents a useful object that is made from some particular material. The problem is that the tool sometimes breaks when it is being used, depending on its material strength. You will simulate this behavior with this class. |
| - Initialize the class properties **''name''**, **''material''** and ''**working**'' in the constructor, with the first two being passed in and the last one set to the default value of **''True''**. | - Initialize the **''Tool''** class properties **''name''**, **''material''** and ''**working**'' in the constructor, with the first two being passed in and the last one set to the default value of **''True''**. |
| - Add the method **''use''** to the class, which prints out "I can't use this broken [name]" if the tool is not working, prints out "Dang! The [name] just broke!" if a test of material strength fails (see next) or prints out "The [name] really helped!" if nothing catastrophic occurs. | - Add the method **''use''** to the class, which prints out "I can't use this broken [name]" if the tool is not working (''working is False''), prints out "Dang! The [name] just broke!" (ands sets ''working=False'') if a test of material strength fails (see next) or prints out "The [name] really helped!" if nothing catastrophic occurs. |
| - To help with testing the material strength, declare a global dictionary called ''**material_strength**'', keyed on material names (like **''"glass", "plastic", "wood", "metal"''**) and mapping them to strength values between 0 and 100. | - To help with testing the material strength, declare a global dictionary called ''**material_strength**'', keyed on material names (like **''"glass", "plastic", "wood", "metal"''**) and mapping them to strength values between 0 and 100 (your choice). |
| - The test in the **''use''** method of a tool fails if a random value in the 0 to 100 range is higher than the strength of the item's named material. | - The test in the **''use''** method of a tool fails if a random value in the 0 to 100 range is higher than the strength of the item's named material. |
| - Declare a global list of instanced tools (like **''"hammer", "glasses", "blender", "raygun"''**...) and make the program use them all to see if your class works. \\ \\ <code python> | - Declare a global list of instanced tools (like **''"hammer", "glasses", "blender", "raygun"''**...) and make the program use them all to see if your class works. \\ \\ <code python> |
| print mydict["B"] # Prints 30, which is the value associated with the key "B" | print mydict["B"] # Prints 30, which is the value associated with the key "B" |
| </code> | </code> |
| - Make your list of friends now contain a list of touples where the first element is the friend's name like before, but the second element should be a list of 2-3 instanced items in that friend's posession. Make your program pick one person at random, greet them, and then ask to borrow one random item from them and finally try to use that borrowed item. As before, have the program repeat this as many times as you specify or until items have been unsuccessfully used 10 times in a row (you can make the ''**use**'' method return ''**True**'' or ''**False**'' to help you keep track). \\ \\ <code python> | - Make your list of friends now contain a list of tuples where the first element is the friend's name like before, but the second element should be a list of 2-3 instanced tools in that friend's possession. Make your program pick one person at random, greet them, and then ask to borrow one random tool from them and finally try to use that borrowed tool. As before, have the program repeat this as many times as you specify or until tools have been unsuccessfully used 10 times in a row (you can make the ''**use**'' method return ''**True**'' or ''**False**'' to help you keep track). \\ \\ <code python> |
| # HINT: A touple is an immutable sequence, unlike a list which can be modified. | # HINT: A tuple is an immutable sequence, unlike a list which can be modified. |
| mytouple = (3, 5, 7) | mytuple = (3, 5, 7) |
| # HINT: Touples, like other sequences can contain any types of objects | # HINT: Tuples, like other sequences can contain any types of objects |
| mytouple = (3, "Hello", MyClass(5), [7, 6, 4]) | mytuple = (3, "Hello", MyClass(5), [7, 6, 4]) |
| # Any contained object can be referenced | # Any contained object can be referenced |
| print mytouple[1] # Prints "Hello" | print mytuple[1] # Prints "Hello" |
| mytouple[2].show() # Prints "I have x=5 and y=defaultY" | mytuple[2].show() # Prints "I have x=5 and y=defaultY" |
| print mytouple[3][0] # Prints 7 | print mytuple[3][0] # Prints 7 |
| </code> | </code> |
| - Add the function **''fix''** to your program that takes in a single **''Item''** and forces its **''working''** value to **''True''**. Declare a list of names, called **''favorites''**, and instead of quitting after 10 failed attempts at using borrowed items, make the program fix all items posessed by those that have their name appear on the **''favorites''** list, but not the others. Print out the names of those that got their items fixed and let the program borrow a few more items to see if it can now continue it's habit a bit longer. \\ \\ <code python> | - Add the function **''fix''** to your program that takes in a single **''Tool''** and forces its **''working''** value to **''True''**. Declare a list of names, called **''favorites''**, and instead of quitting after 10 failed attempts at using borrowed tools, make the program fix all tools possessed by those that have their name appear on the **''favorites''** list, but not the others. Print out the names of those that got their tools fixed and let the program borrow a few more tools to see if it can now continue it's habit a bit longer. \\ \\ <code python> |
| # HINT: Finding maches beween two lists | # HINT: Finding matches between two lists |
| listA = [1, 3, 5, 7, 9] | listA = [1, 3, 5, 7, 9] |
| listB = [4, 5, 6, 8, 9] | listB = [4, 5, 6, 8, 9] |
| print str(x)+" is common!" # Prints "5 is common!, 9 is common!" | print str(x)+" is common!" # Prints "5 is common!, 9 is common!" |
| </code> | </code> |
| - Instead of using the **''favorites''**, only fix items for those that exist in the online Símaskrá (http://www.simaskra.is). \\ \\ <code python> | - Instead of using the **''favorites''**, only fix tools for those that exist in the online Símaskrá (http://www.simaskra.is). \\ \\ <code python> |
| # HINT: Reading and parsing a source on the Internet | # HINT: Reading and parsing a source on the Internet |
| import urllib # Module for simple Internet sockets | import urllib # Module for simple Internet sockets |
