Re: [Tutor] printing an acronym
On Sat, 24 Sep 2005 [EMAIL PROTECTED] wrote: How could I get the following to print out an acronym for each phrase entered such as if I entered random access memory it word print out RAM? Hello, Just out of curiosity, are you already familiar with Python's lists? If so, then you might want to try the slightly easier problem of pulling out acronyms out of a list of words. Extracting an acronym out of a list like: [International, Business, Machines] == IBM is not too bad, and is one step toward doing the original problem on the phrase International Business Machines. Tutorials like: http://www.freenetpages.co.uk/hp/alan.gauld/tutseq2.htm and the other tutorials on: http://wiki.python.org/moin/BeginnersGuide/NonProgrammers should talk about lists. Please feel free to ask questions here! ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] (no subject)
On Sat, 24 Sep 2005 [EMAIL PROTECTED] wrote: How would I get the following program to accept inputs of exam scores from 0-100 with A being 100-90, B being 89-80, C being 79-70, D being 69-60, and F being everything less than 60? Hello, Are you familiar with if/elif/else? These control-flow statements should help you express the above grading idea fairly straightforwardly. For experienced programmers, there is a module in the Standard Library that does pretty much what you want. I'll link to it below, but you probably won't want to use it: learn to use if/elif/else first; I'd hate to stunt your Python learning. *grin* Link for experienced programmers: http://www.python.org/doc/lib/bisect-example.html ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Using new style classes and __slots__
Oh wait, I get it - you are passing bound methods to property(). So um is bound to the instance when you access self.getA. Use Strange.getA instead of self.getA, then use the normal signatures. Ahh... I get it. But I don't get why you are doing this at all? Because some of the objects I'm working with have 65 attributes, each one needs to be typechecked and then passed down the line. As the knowledge of the file structure I'm reading is not complete, as it changes I'll have to update it. At the moment, what I'm doing is I have a docstring like so - Type: Track Item Tuple format: [0] header_id (4string) [1] header_length (int) [2] total_length (int)-- (Of child strings + header) [3] num_of_strings (int) -- (Above child strings) ... ... [62] unknown (int) [63] unknown (int) [64] unknown (int) and a struct string 4s6ih2c7i2h12iq2c3h10iq17i Now, as knowledge of the format changes, so does that tuple format and struct string. I have a convenience function which parses my docstring for each class and creates a module dictionary of attribute name, type and length if applicable. It can also create a struct string based on those types. I can then call a generic set for all those attributes, which will pull the type out of the dict and check it, and also acts as a repository for attribute names. If the file structure changes, I simply update my doc string, call my convenience function, and my name:type dictionary is updated, as is my struct string. Alternatively, I can manually add header_id = property(..) and manually update the struct string and the doc string when something changes. However, on reflection, I just figured out that it'll be simpler using __setattr__ for this one, as I won't be able to get the attribute name using property() unless I use a function factory to generate 127 functions and use func.__name__, when using __setattr__ and a dictionary lookup is going to be much simpler. But, it's good to know how to use property. I can think of a couple of uses it for it. I wasn't thinking far enough ahead in this case, so please forgive my emailed meanderings. It is passing self twice, because you are using a bound method as the property method rather than an unbound method. Erk. That seems obvious in hindsight, like a cryptic crossword answer. Once again, my lack of experience with this sorta stuff comes up. I've never really dealt with indepth oo stuff before, so this has all been a gigantic learning curve. Thanks for your help on this, Kent. This is a hassle for me because I'm a lazy typist, so I've been using setattr() to pull attribute names out of a list. And the first argument setattr() requires is an object, and self doesn't work outside of a method, and using the class name leads to no attribute being set. I don't understand this at all, can you give an example? Basically, I just found that outside methods, self gives a NameError. The examples are all needless now, anyway. Regards, Liam Clarke ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Error checking - very basic question
I have a call which needs to reply 2.1 or 2.8 and report an error if not: def ask_dau_version(): Determine the product issue of the DAU. dau_version = None while dau_version not in (2.8, 2.1): dau_version = raw_input(\n\tIs the DAU a version 2.1 or 2.8, please enter only 2.1 or 2.8 ) print\n\t\aError! - please enter only 2.1 or 2.8. else: print return dau_version I can see why it isn't working, the error message is in the wrong place, but I can't see a simple way around it (wood for the trees) Gaz ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] numbers from a name
On Sun, 2005-09-25 at 01:06 -0400, [EMAIL PROTECTED] wrote:
How could I change the program to accept something like: John Bob
Zelle Python or Kip Rada?
If it works for you with one word, all you need to make it accepts more
is to add the space character with a weight of zero to table.
table[' '] = 0
Alternatively, while creating the whole table:
table = {'a': 1, 'b': 2, 'c': 3, 'd': 4, 'e': 5, 'f': 6, 'g': 7,
'h': 8, 'i': 9, 'j': 10, 'k': 11, 'l': 12, 'm': 13, 'n': 14,
'o': 15, 'p': 16, 'q': 17, 'r': 18, 's': 19, 't': 20, 'u': 21,
'v': 22, 'w': 23, 'x': 24, 'y': 25, 'z': 26, ' ': 0}
Likewise, you could add the ',' (also with a weight of 0) for names like
Bob, Bob.
Ziyad.
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Re: [Tutor] Error checking - very basic question
Garry Rowberry wrote:
def ask_dau_version():
Determine the product issue of the DAU.
dau_version = None
while dau_version not in (2.8, 2.1):
dau_version = raw_input(\n\tIs the DAU a version 2.1 or 2.8, please
enter only 2.1 or 2.8 )
print\n\t\aError! - please enter only 2.1 or 2.8.
else:
print
return dau_version
I can see why it isn't working, the error message is in the wrong place, but
I can't see a simple way around it (wood for the trees)
How about using a while True loop that you break out of only when a
correct value has been identified:
while True:
dau_version = raw_input('blabla')
if dau_version in (2.8, 2.1):
break
else:
print Error
--
Yours,
Andrei
=
Mail address in header catches spam. Real contact info (decode with rot13):
[EMAIL PROTECTED] Fcnz-serr! Cyrnfr qb abg hfr va choyvp cbfgf. V
ernq gur yvfg, fb gurer'f ab arrq gb PP.
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Re: [Tutor] creating strings
I will use simple function:
def getscore(val): if 90 val =100: return 'A' elif val = 80: return 'B' elif val = 70: return 'C' elif val = 60: return 'D'
else: return 'F' def main(): g = input('Enter score:') print 'the score of the exam is %s' % (getscore(int(g)))Cheers,
pujo
On 9/25/05, [EMAIL PROTECTED] [EMAIL PROTECTED]
wrote:
Hello How would I get the following program to accept inputs of exam scores from 0-100 with A being 100-90, B being 89-80, C being 79-70, D being 69-60, and F being everything less than 60?
import string def main(): scores = [F, D, C, B, A] g = input(Enter a score number (0-100): ) print The score of your exam is, scores [g-0] + .
main() ___Tutor maillist - Tutor@python.org
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Re: [Tutor] Error checking - very basic question
Hi Garry, dau_version = None while dau_version not in (2.8, 2.1): dau_version = raw_input(\n\tIs the DAU a version 2.1 or 2.8, please enter only 2.1 or 2.8 ) print\n\t\aError! - please enter only 2.1 or 2.8. else: print I don't know what they else is meant to do, I take it that's when your while loop exits. Here's how your code will run - dau_version = None (while statement) is dau_version 2.8 or 2.1? Nope. dau_version = rawinput(Is...2.8) print Error! - please enter only 2.1 or 2.8 is dau_version 2.8 or 2.1? Yep - exit loop. Try doing it like this - while True: dau_version = raw_input(\n\tIs the DAU a version 2.1 or 2.8, please\ enter only 2.1 or 2.8 ) if dau_version in (2.1, 2.8): break print Error! - please enter only 2.1 or 2.8 What will happen is that your while loop will loop forever (as True is always True). However, if dau_version is 2.1 or 2.8, the break command will be called, which exits out of the loop at that point. So your loop looks like this now - while True: get dau_version if dau_version is right, exit loop here. print error message Regards, Liam Clarke On 9/25/05, Garry Rowberry [EMAIL PROTECTED] wrote: I have a call which needs to reply 2.1 or 2.8 and report an error if not: def ask_dau_version(): Determine the product issue of the DAU. dau_version = None while dau_version not in (2.8, 2.1): dau_version = raw_input(\n\tIs the DAU a version 2.1 or 2.8, please enter only 2.1 or 2.8 ) print\n\t\aError! - please enter only 2.1 or 2.8. else: print return dau_version I can see why it isn't working, the error message is in the wrong place, but I can't see a simple way around it (wood for the trees) Gaz ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] creating strings
[EMAIL PROTECTED] wrote: How would I get the following program to accept inputs of exam scores from 0-100 with A being 100-90, B being 89-80, C being 79-70, D being 69-60, and F being everything less than 60? import string There's no point in importing string. def main(): scores = [F, D, C, B, A] g = input(Enter a score number (0-100): ) print The score of your exam is, scores [g-0] + . main() You could chain a bunch of if-statements. if g is between X1 and Y1: result is Z1 else if g is between X2 and Y2: result is Z2 else if ... -- Yours, Andrei = Mail address in header catches spam. Real contact info: ''.join([''.join(s) for s in zip( [EMAIL PROTECTED] pmfe!Pes ontuei ulcpss edtels,s hr' one oC., rjc5wndon.Sa-re laed o s npbi ot.Ira h it oteesn edt C)]) ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Error checking - very basic question
Hi Garry, break is essential for while loops like that one. You'll see that construct often enough in Python. While 1 or While True followed by an if condition : break Bit awkward, makes me miss the do - while construct. continue is very useful in for loops. Let's say I have a set of numbers, but I don't want to work with the number 5. I have a phobia or something. numbers = [1,2,3,4,5,6,7] for number in numbers: if number == 5: continue print number Continue will exit the loop at that point, but will continue with the next value in numbers. Try swapping break for continue. On 9/25/05, Garry Rowberry [EMAIL PROTECTED] wrote: Thank you Liam, Works a treat, must look at the break and continue commands in more detail Regards Gaz -Original Message- From: Liam Clarke [mailto:[EMAIL PROTECTED] Sent: Sunday, September 25, 2005 12:10 PM To: Garry Rowberry; Python Tutor Mailing List Subject: Re: [Tutor] Error checking - very basic question Hi Garry, dau_version = None while dau_version not in (2.8, 2.1): dau_version = raw_input(\n\tIs the DAU a version 2.1 or 2.8, please enter only 2.1 or 2.8 ) print\n\t\aError! - please enter only 2.1 or 2.8. else: print I don't know what they else is meant to do, I take it that's when your while loop exits. Here's how your code will run - dau_version = None (while statement) is dau_version 2.8 or 2.1? Nope. dau_version = rawinput(Is...2.8) print Error! - please enter only 2.1 or 2.8 is dau_version 2.8 or 2.1? Yep - exit loop. Try doing it like this - while True: dau_version = raw_input(\n\tIs the DAU a version 2.1 or 2.8, please\ enter only 2.1 or 2.8 ) if dau_version in (2.1, 2.8): break print Error! - please enter only 2.1 or 2.8 What will happen is that your while loop will loop forever (as True is always True). However, if dau_version is 2.1 or 2.8, the break command will be called, which exits out of the loop at that point. So your loop looks like this now - while True: get dau_version if dau_version is right, exit loop here. print error message Regards, Liam Clarke On 9/25/05, Garry Rowberry [EMAIL PROTECTED] wrote: I have a call which needs to reply 2.1 or 2.8 and report an error if not: def ask_dau_version(): Determine the product issue of the DAU. dau_version = None while dau_version not in (2.8, 2.1): dau_version = raw_input(\n\tIs the DAU a version 2.1 or 2.8, please enter only 2.1 or 2.8 ) print\n\t\aError! - please enter only 2.1 or 2.8. else: print return dau_version I can see why it isn't working, the error message is in the wrong place, but I can't see a simple way around it (wood for the trees) Gaz ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Exception handling - syntaxerror?!
On Sun, 2005-09-25 at 19:44 +0530, Krishna wrote: snip Think the mail system screwed up the formatting! But am fairly sure that I have indented it correctly in the console. Try and Except are in the column. Any other hints? Make sure you're not mixing tabs and spaces. A lot of editors uses the ASCII tab character when hitting the Tab key, while other inserts 8 (or 4 on some cases) ASCII space character in that case. If you're sure try: and except: are on the same column, then the above advice is the only one I have for you. Sorry. BTW, I had just added the last print statement to see how try...except worked. Thanks for the response. You're welcome. -Kris Ziyad. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] __getattr__ causes TypeError
Hi,
I experienced a strange side effect using a custom __getattr__ method.
For a certain attribute, I'd like to return the value of another attribute if
the former is not present. So I wrote:
def __getattr__(self, attrname):
if attrname == 'own_type': return self.child_type
else: AttributeError, attrname
But if I include this in my base class, I get a TypeError somewhere else:
File /Users/jan/Sites/janeden/cgi-bin/Pythonsite/Show.py, line 24, in
Populate
self.page_head = re.sub('%%author%%', self.first_name+' '+self.last_name,
self.page_head)
TypeError: unsupported operand type(s) for +: 'NoneType' and 'str'
How can this possibly be related? I am clueless.
Best,
Jan
--
If all else fails read the instructions. - Donald Knuth
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