[Tutor] Tutor Digest, Vol 104, Issue 8

[zouzhberk]

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>Today's Topics:
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>   1. Re: html checker (Alan Gauld)
>   2. HELP! (Mark Rourke)
>   3. python help? (patrick Howard)
>
>
>----------------------------------------------------------------------
>
>Message: 1
>Date: Tue, 02 Oct 2012 00:46:31 +0100
>From: Alan Gauld <alan.gauld at btinternet.com>
>To: tutor at python.org
>Subject: Re: [Tutor] html checker
>Message-ID: <k4da0m$919$1 at ger.gmane.org>
>Content-Type: text/plain; charset=ISO-8859-1; format=flowed
>
>On 01/10/12 20:59, Matthew Dalrymple wrote:
>
>> i don't really understand the pop and push or even stacks for that
>> matter...the professor i have isn't really the best at teaching...so if
>> anyone could give me a hand with any of this that would be appreciated
>
>The Raw materials topic in my tutor has a short intro to stacks. It 
>says, in part:
>----------------
>Stack
>
>Think of a stack of trays in a restaurant. A member of staff puts a pile 
>of clean trays on top and these are removed one by one by customers. The 
>trays at the bottom of the stack get used last (and least!). Data stacks 
>work the same way: you push an item onto the stack or pop one off. The 
>item popped is always the last one pushed. This property of stacks is 
>sometimes called Last In First Out or LIFO. One useful property of 
>stacks is that you can reverse a list of items by pushing the list onto 
>the stack then popping it off again. The result will be the reverse of 
>the starting list. Stacks are not built in to Python, VBScript or 
>JavaScript. You have to write some program code to implement the 
>behavior. Lists are usually the best starting point since like stacks 
>they can grow as needed.
>-----------------
>
>As c smith points out, Python lists have a pop/push mechanism as 
>standard which makes implementing a stack in Python fairly trivial.
>
>To expand on how reversing works consider pushing the string foo onto 
>the stack then popping it off again:
>
>s = 'foo'
>stack = []
>stack.push(s[0])  # stack -> ['f']
>stack.push(s[1])  # stack -> ['o','f']
>stack.push(s[2])  # stack -> ['o','o','f']
>
>c1 = stack.pop()  # stack -> ['o','f'], c1 = 'o'
>c2 = stack.pop()  # stack -> ['f'], c1 = 'o', c2 = 'o'
>c3 = stack.pop()  # stack -> [], c1 = 'o', c2 = 'o', c3 = 'f'
>
>print c1+c2+c3  # prints 'oof' the reverse of s
>
>HTH,
>
>-- 
>Alan G
>Author of the Learn to Program web site
>http://www.alan-g.me.uk/
>
>
>
>------------------------------
>
>Message: 2
>Date: Sun, 30 Sep 2012 15:31:47 -0400
>From: Mark Rourke <mark.rourke7 at gmail.com>
>To: tutor at python.org
>Subject: [Tutor] HELP!
>Message-ID: <50689E23.4050901 at gmail.com>
>Content-Type: text/plain; charset="iso-8859-1"; Format="flowed"
>
>hello, I am a college student in my first year of computer programming, 
>I was wondering if you could look at my code to see whats wrong with it.
>
># Mark Rourke
># Sept 29, 2012
># Write a program to calculate the sales tax at the rate of 4% and 2% 
>respectively
># Thereafter compute the total sales tax (sum of the state tax and the 
>county tax)
># and the total purchase amount (sum of the purchase amount and the 
>total sales tax).
># Finally, display the amount of purchase, the state sales tax, the 
>county sales tax,
>#the total sales tax and the total amount of the sale.
>
>#Variable Declarations
>#Real purchaseAmount, stateSalesTax, countySalesTax, totalSalesTax, 
>totalPurchaseAmount
>#Constant Real SALES_TAX = 0.4, COUNTY_TAX = 0.02
>
>#Display "Input Purchase Amount: $"
>
>#input the hours worked and hourly wage wage
>
>SALES_TAX = 0.4
>
>COUNTY_TAX = 0.02
>print("----------------------------------------------------------")
>print(("This program calculates the sales tax at the rate of 4% and 2% 
>respectively, as well sum of the state tax"))
>print("----------------------------------------------------------")
>
>purchaseAmount = input("Please input the Purchase Amount: $")
>
>#Calculate the State Sales Tax, County Sales Tax, Total Sales Tax, Total 
>Purchase Amount
>
>purchaseAmount = int(purchaseAmount)
>
>stateSalesTax = int(purchaseAmount * SALES_TAX)
>
>countySalesTax = int(purchaseAmount * COUNTY_TAX)
>
>totalSalesTax = int(stateSalesTax + countySalesTax)
>
>totalPurchaseAmount = int(purchaseAmount + totalSalesTax)
>
>#Output the results
>
>Display ("Purchase Amount:$") purchaseAmount
>Display ("The State Sales Tax $") SALES_TAX
>Display ("The County Sales Tax: $") COUNTY_TAX
>Display ("The Total Sales Tax: $") totalSalesTax
>Display ("The Total Amount of the Purchase: $") totalPurchaseAmount
>
>-- 
>
>Mark Rourke
>
>T: 705-728-6169
>M: 705-331-0175
>E: Mark.Rourke7 at gmail.com
>
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>------------------------------
>
>Message: 3
>Date: Sun, 30 Sep 2012 01:02:57 -0500
>From: patrick Howard <philoant at gmail.com>
>To: tutor at python.org
>Subject: [Tutor] python help?
>Message-ID: <B723A488-EC4B-4E2F-AD02-EF8AB9A94175 at gmail.com>
>Content-Type: text/plain; charset="windows-1252"
>
>I have to write a program that takes an input file, with students names and various grades.
>My vindictive teacher also added grades that are not supposed to count, so I need to pick the grades that are 'HM1-4"; not HW, or TEST or anything else.
>Then when these are listed in order with that persons name, sort the list alphabetically. I know that this is '.sort; 
>But, how do I get it to sort only names, AND keep the right grades with them. Below is a list of parameters? Can you help me please?
>
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>End of Tutor Digest, Vol 104, Issue 8
>*************************************