Re: [Tutor] Creating a list from other lists
>> It's an HTML post. > > Not according to the version of Thunderbird I am using, which shows it > as a plain text email. > > I suspect that the HTML attachment may be invalid HTML, understandable > by Gmail and possibly nothing else. Typical of Google :( Looking at the email source it clearly shows as being mimetype "multipart" with both a plaintext and HTML part. I don't think you can much criticise GMail for interpreting and attempting to render an HTML email as HTML. The biggest culprit here IMHO was the sending mail client that generated a broken text mode version of the email's intended formatting by dropping the indentation (and if the HTML is broken, generated broken HTML to boot as well.) Walter ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Creating a list from other lists
On 23/10/12 19:51, Walter Prins wrote: It's an HTML post. Not according to the version of Thunderbird I am using, which shows it as a plain text email. I suspect that the HTML attachment may be invalid HTML, understandable by Gmail and possibly nothing else. Typical of Google :( Looking at the email source it clearly shows as being mimetype "multipart" with both a plaintext and HTML part. I don't think you can much criticise GMail for interpreting and attempting to render an HTML email as HTML. Perhaps not, but I can criticize Gmail for offering such an anti-feature in the first place. The biggest culprit here IMHO was the sending mail client That would be Gmail, almost certainly. that generated a broken text mode version of the email's intended formatting by dropping the indentation (and if the HTML is broken, generated broken HTML to boot as well.) I don't actually know if the HTML part is broken or not. I saved it and opened it in Firefox, and Firefox rendered it as raw text showing the tags. Perhaps that just means my test was faulty. Either way though, I'm sick to the back teeth of Google-related technologies being user hostile. Whether it is the horror that Google Groups has become, Google's search engine tracking and bubbling you when you search, Google illegally installing tracking cookies AND THEN LYING ABOUT IT to the American FTC, the awfulness of their image search interface (which just about every search engine now apes), and their efforts to link everything you do on the Internet to a Google account which can be matched to your offline identity, I think their motto is now best described as "Do be evil". -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Which is better Practice and why
On 23/10/12 12:53, Devin Jeanpierre wrote: On Mon, Oct 22, 2012 at 8:54 PM, Steven D'Aprano wrote: package.__main__.py is designed to be run as a script, and not to be imported. But that doesn't mean that there's no good purpose for importing it. If your package is non-trivial, you ought to have tests for it, including package.__main__. Those tests will probably want to import the module, not necessarily run it as a script. I think you will find that it is never the case that __name__ != '__main__' in a file called "__main__.py". I think you'll find that you're wrong there :) [steve@ando ~]$ mkdir package [steve@ando ~]$ touch package/__init__.py [steve@ando ~]$ echo "print(__name__)" > package/__main__.py [steve@ando ~]$ python package __main__ [steve@ando ~]$ python -c "import package.__main__" package.__main__ If I want to test something, I put it in another file. Yes. And how do you import the __main__.py module to test it, without it executing? My __main__.py file will generally look something like this: from . import game game.Game().run() Well, that's probably trivial enough that it requires no testing other than "does __main__.py exist?". -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Creating a list from other lists
On Tue, Oct 23, 2012 at 4:51 AM, Walter Prins wrote: > > Looking at the email source it clearly shows as being mimetype > "multipart" with both a plaintext and HTML part. I don't think you > can much criticise GMail for interpreting and attempting to render an > HTML email as HTML. The biggest culprit here IMHO was the sending > mail client that generated a broken text mode version of the email's > intended formatting by dropping the indentation (and if the HTML is > broken, generated broken HTML to boot as well.) The message looks to have been sent with Gmail's webmail client. The problem I think starts with Webkit. When the user presses in a rich text box, instead of tabbing between fields on the page, it inserts a element. I tested how Gmail handles this by creating a simple HTML file containing the following: for x, y , z in zip(a, b, c): L.extend([x, y, z])print L I rendered this in Firefox and copied it into a new rich text email. Gmail stripped out the tab characters before rendering the plain text section as follows: for x, y , z in zip(a, b, c): L.extend([x, y, z]) print L They certainly could be smarter when it comes to spans with "whitespace:pre" styling, but it's better if users would just think to use plain text when posting code. That said, plain text with Gmail has its own pitfalls. To render it correctly with a monospace font in the web client you need to use something like Stylish to hack Gmail's CSS. But, more importantly, you have to be wise to Google's line wrapping at 69 characters (no RFC requires this). It doesn't give you a live preview. Instead you have to manually wrap code at 69 columns in an IDE and paste it into the text box. Otherwise your code will probably get mangled. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Which is better Practice and why
On Tue, Oct 23, 2012 at 5:59 AM, Steven D'Aprano wrote: > I think you'll find that you're wrong there :) Oops. >> If I want to test something, I put it in another file. > Yes. And how do you import the __main__.py module to test it, without > it executing? How do you test the body of code in the "if __name__ == '__main__'" block, without it executing? -- Devin ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Which is better Practice and why
On 23 October 2012 02:17, Devin Jeanpierre wrote: > On Mon, Oct 22, 2012 at 8:42 PM, Steven D'Aprano wrote: >> If you do that, and the module directly or indirectly imports itself >> while it is running as a script, you may run into trouble. But writing >> a dual-purpose module that is usable as an importable module or as a >> stand-alone script is not problematic in itself. > > Yes. However, it is somewhat hard to guarantee that a module won't > indirectly import itself for a large codebase. It certainly sometimes > happens by accident. I guess this is the crux of the issue. If your script is part of and depends on a large codebase then you may as well place all of its code elsewhere in the codebase. The script then serves simply as an entry point and its presence in the project won't hinder your ability to move all the code it uses around to suit its relationship to the rest of the codebase. Importable scripts are useful when you have a codebase that is smaller. In particular if your codebase is one single script (a common case) then you should always use if __name__ == "__main__" unless the script is trivial and/or, as Steven says, you're feeling lazy. Doing this means that you can test your script and its functions by importing the script in the interactive interpreter and that you can reuse the script as a module in some other project If your codebase is a single module rather than a script, giving it an if __name__ == "__main__" block allows someone to perform a common task with the module (or perhaps run its tests) using the -m interpreter option without needing to turn a single file project into a double file project: $ python -m mymodule arg1 arg2 This is often better than creating a separate script to serve as a redundant entry point (redundant since the module can already serve as its own entry point). Once you have one importable script A.py you can then place another script B.py in the same folder have B import and use some of A's code. As Eryksun has said making this work both ways (having B also import from A) can lead to problems. If you find yourself wanting to do that then you have probably organised your code badly. As a solution consider moving all of the common code into one of A or B or into a new module/script C. Another factor not mentioned yet is that the use of if __name__ == "__main__" is so ubiquitous that using it in your own script communicates something to most people who read it (including yourself). If I know that X.py is intended to be used as a script and I want to read it to find out how it works, one of the first things I would do is search for that line. My natural assumption is that no non-trivial execution occurs outside of that if-block (this is almost always true if I wrote the script and it is longer than about 10 lines). Oscar ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Iterators, example (need help)
On Mon, Oct 22, 2012 at 6:30 PM, Bryan A. Zimmer wrote:
>
> ignore1='''
>
> This program works to do what I set out to do as a first step
> BAZ 10/19/2012
>
> '''
If this isn't meant to be a module docstring, leave it where it is,
but remove the assignment to ignore1. Unassigned triple-quoted strings
are the closest thing in Python to C-style /* multi-line comments */.
This works because the compiler ignores unassigned literal
strings/numbers, as the following example shows:
>>> code = compile('''\
... 0
... """
... multi-line
... comment
... """
... ''', filename='', mode='exec')
>>> code.co_consts
(None,)
If the number 0 and the string were't ignored, they'd be in co_consts.
This is a tuple of immutable objects used by Python bytecode, such as
literal numbers, strings (including unicode), tuples, and the
singleton None. 3.x adds True, False, Ellipsis, and frozenset. (I
probably forgot something, but you get the idea.)
If the string is meant to be a docstring, on the other hand, put it on
the first line before your imports. In this special case, the compiler
creates a __doc__ constant, which is assigned as an attribute of the
module. Here's a skeleton of the process:
>>> code = compile('"a docstring"', '', 'exec')
>>> dis.dis(code)
1 0 LOAD_CONST 0 ('a docstring')
3 STORE_NAME 0 (__doc__)
6 LOAD_CONST 1 (None)
9 RETURN_VALUE
>>> mod = types.ModuleType('mod')
>>> vars(mod)
{'__name__': 'mod', '__doc__': None}
>>> exec code in vars(mod)
>>> vars(mod).keys()
['__builtins__', '__name__', '__doc__']
>>> mod.__doc__
'a docstring'
Executing the code in the module also added __builtins__ to the
namespace, so built-in functions and types are available. A normal
import would also set the __file__ and __package__ attributes.
Regarding your Env class, I hope you'd use os.environ.iteritems() in practice.
> def __next__(self,master=None):
In 2.x, this should be next(). In 3.x, it's __next__().
http://docs.python.org/library/stdtypes.html#iterator.next
http://docs.python.org/py3k/library/stdtypes.html#iterator.__next__
StringVar objects s1 and s2 should be attributes of the App instance,
not global variables. Also, as it is, since you aren't rebinding s1
or s2 in next(), there's no technical reason to declare them with the
'global' keyword in next().
http://docs.python.org/reference/simple_stmts.html#the-global-statement
Don't needlessly parenthesize expressions in statements such as if,
return, etc. Python doesn't require it, so it's just symbol noise. For
example, use:
if x:
return x
x, y, d, v, and i are unhelpful attribute names. I strongly recommend
using descriptive names such as current_key, current_value. It helps a
lot when you're updating code later on, especially if you aren't the
original author.
As to the next() method itself, I'd keep it simple. Return the
key/value tuple if self._index < len(self.keys), and otherwise raise
StopIteration. I wouldn't conflate the implementation of next() with
updating the StringVar instances s1 and s2. The "Next" button can use
a method defined in App to iterate the Env instance and update the
strings.
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Re: [Tutor] iterators, need help
I just wanted to say thanlk you to those who took the time to answer my request for help. It is very much appreciated. Bryan A Zimmer ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] blackJack problem
player1.py > http://pastebin.com/jzv1Hhs1blackjack.py > http://pastebin.com/Vj3sp3Ca ok the problem im having is with the GetBet function...i need it so you start with 1000 it will bet 5 everytime...if i win it adds 5 if i lose it subtracts 5 if we tie nothing changes. I think this is right for the most part except it says that it can call it before reference. I thought by having a value outside of the functions made the value global. Am i somewhat on the right track? any help would be appriciated... Oh i also forgot to mention that even though im not using all the parameters they have to be there because the professor wants to be able to run other peoples "player1.py" files on my game. thanks Matthew D ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blackJack problem
Matthew Dalrymple writes: > I thought by having a value outside > of the functions made the value global. Not quite. To change the global value in a function you also need to declare it as global inside the function. Otherwise it will create a new local variable that has no effect on the global one. Also by declaring a parameter of your function with the same name as the global you confuse things. Don't do that. Am i somewhat on the right track? > > any help would be appriciated... > > Oh i also forgot to mention that even though im not using all the parameters > they have to be there because the professor wants to be able to run other > peoples "player1.py" files on my game. Interesting concept. And if the other peoples files are calling your functions with values in those parameters you will just ignore them I presume? Hmmm, that should produce some interesting results... -- Alan G Author of the Learn to Program web site http://www.alan-g.me.uk/ Playing with gnus and possibly screwing it up!! ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] Retrieving numbers from a text
*Problem*: Analyze a chaotic one-dimensional map: Write a program
OneDMapAnalyze.py that reads the data in OneDMap.txt. Calculate the mean
value of the iterates, printing the result to the terminal; again annotate
the output so that it is understandable. Determine the fraction of iterates
that have x > 0.5. Also, print out that result.
*The previous problem that I have already done:*
Iterate a chaotic one-dimensional map: Write a program OneDMapIterate.py that
iterates the function f(x) = 4.0 x ( 1 - x ). First, set the initial
condition x = 0.3. Then apply f(x) repeatedly to each new x. Iterate for
100 steps, printing on each line the iteration number and the successive x
values to file OneDMap.txt.
My program:
#Imports math functions
from math import *
#Initial condition for x
x = 0.3
#Opens onedmap.txt file and writes to it
file = open('onedmap.txt','w')
#Loop, replaces old x with new x i amount of times
for i in range(1,101):
x = 4.0*x*(1.0-x)
#Writes contents of loop to file
print >> file, 'Iterate number ', i, ': ', x
#Closes file
file.close()
My problem is, I don't know how to get ONLY the numbers from the
OneDMap.txt file. Also, assuming that I am able to do just that, how would
I get them into an array?
--
tell me i can't do it, then i'll prove you wrong!
facebook me
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Re: [Tutor] Retrieving numbers from a text
On 23/10/12 23:45, Rufino Beniga wrote: First, you realize I hope that we don;t do homework for you but we will try to help steer you the right way... So the simple answer is... > -- > tell me i can't do it, then i'll prove you wrong! OK, You can't do it. Is that enough? I thought not, read on... *_The previous problem that I have already done:_* Iterate a chaotic one-dimensional map: Write a program OneDMapIterate.py that iterates the function f(x) = 4.0 x ( 1 - x ). First, set the initial condition x = 0.3. Then apply f(x) repeatedly to each new x. Iterate for 100 steps, printing on each line the iteration number and the successive x values to file OneDMap.txt. My program: #Writes contents of loop to file print >> file, 'Iterate number ', i, ': ', x Note you are writing more than you were asked to to the file. This slightly complicates the second problem... but only slightly. My problem is, I don't know how to get ONLY the numbers from the OneDMap.txt file. Also, assuming that I am able to do just that, how would I get them into an array? One thing at a time. Can you read a line from the file as a string? Can you split a string into its constituent parts? In this case they should be: 'Iterate number ' i ':' x Can you extract the 2nd and 4th items (do you see why writing more than you were asked complicates it?) Can you convert strings to numbers, specifically integers and floats? Now the second question: Can you create a new empty list? Can you append items to that list? Putting them together: Can you write a loop that -reads a line from the file -extracts the data you want -appends it to your list If you can do the above you have pretty much 'proved me wrong'... If not come back with more specific questions. -- Alan G Author of the Learn to Program web site http://www.alan-g.me.uk/ ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Retrieving numbers from a text
On 24/10/12 09:45, Rufino Beniga wrote:
My problem is, I don't know how to get ONLY the numbers from the
OneDMap.txt file. Also, assuming that I am able to do just that, how would
I get them into an array?
What we need to see is typical contents of your file. I expect it looks
something like this:
iterate number 562 0.4532888
iterate number 563 0.3872701
iterate number 564 0.9100345
iterate number 565 0.0027318
iterate number 566 0.6661924
and so forth.
In that case, you can read the final column by reading each line, splitting
into words, and taking only the last one. Since this is homework, I'll give
you the pieces you need to use, you should be able to assemble them into
working code yourself.
To read each line in a file:
for line in open("name of file"):
process line
Replace "process line" with the actual code you need.
To build up a list of numbers:
numbers = []
numbers.append(0.3)
numbers.append(0.9736)
numbers.append(0.3209)
Normally you would put the "numbers.append(x)" into a loop,
something like this:
numbers = []
for item in many_items:
value = process(item)
numbers.append(value)
Hint: reading a file gives you a loop, one for each line. You
want to process each line to get a number, then append that
number to the list of numbers.
You will have lines of text that look like this:
line = "iterate number 563 0.3872701"
which is a string, you need to extract the last column and
turn it into a float. Hints:
use line.split() to split the line into four words:
words = line.split()
print words
=> prints ['iterate', 'number', '563', '0.3872701']
use words[-1] to extract the last word
use function float(word) to convert it from a string to a
number.
If you put all those pieces together, it should take no more
than a dozen lines of code to read the file, and extract the
final column into a list of numbers.
Good luck!
--
Steven
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[Tutor] Strings.
Dear Sir/Madam, I am new to python I have a question. It is as follows: Suppose *s* is a variable and *s* stores empty string s="" Now if we write following statement print(s[0]) # it gives error print(s[0:])# it does not give error print (s[13:13]) # this too does not give erro why? Regards, Nitin ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Doubt!
On 10/23/2012 07:14 PM, Nitin Ainani wrote: > Dear Sir/Madam, > > I am new to python I have a question. It is as follows: > > Suppose *s* is a variable and *s* stores empty string > > s="" > Now if we write following statement > > > print(s[0]) # it gives error There is no 0th character, so it's an error. If they had wanted to avoid an error, they'd have had to return None or some other flag, and that's not pythonic. > > print(s[0:])# it does not give error A slice is more tolerant, by definition. It gives you all the items in the range you specify, and the resulting string (in this case) is equal to the original one. > why? > > -- DaveA ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Doubt!
On 24/10/12 10:14, Nitin Ainani wrote: Dear Sir/Madam, I am new to python I have a question. It is as follows: Suppose *s* is a variable and *s* stores empty string s="" Now if we write following statement print(s[0]) # it gives error print(s[0:])# it does not give error why? Because indexing a string returns the character at that index. If the index is out-of-bounds, there is nothing to return and an error will be raised: py> s = "hello world" py> s[0] 'h' py> s[6] 'w' py> s[100] Traceback (most recent call last): File "", line 1, in IndexError: string index out of range The colon : tells Python to use a slice. Slices look like: [start:end:step] where step defaults to 1 if it is not given, start defaults to 0, and end defaults to the length of the string. py> s = "hello world" py> s[0:5] 'hello' py> s[:5] 'hello' py> s[1:9] 'ello wor' If either start or end is out of bounds, the result is truncated at the ends of the string: py> s[1:100] 'ello world' If start is greater-or-equal to end, it is an empty slice, and the empty string is returned: py> s[6:3] '' So the slice s[0:] says "give me the slice of the string s starting at position 0 and extending up to the end of the string". In the case of the empty string, since the string is empty, there are no characters and every index is out-of-bounds. So s[0] will raise an error. But the slice s[0:] is an empty slice, and will return the empty string. Slicing can be considered to be a short-cut for using a for-loop and range. s[start:end:step] is like this function: def slice_copy(s, start, end=None, step=1): if end is None: end = len(s) new = [] for i in range(start, end, step): new.append(s[i]) return ''.join(new) (except that real slicing can deal with out-of-bounds start and end as well.) If you study slice_copy, you should understand why an empty slice returns the empty string. -- Steven ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Doubt!
On 10/23/2012 04:14 PM, Nitin Ainani wrote: Dear Sir/Madam, I am new to python I have a question. It is as follows: Suppose *s* is a variable and *s* stores empty string s="" Now if we write following statement print(s[0]) # it gives error print(s[0:])# it does not give error why? See http://docs.python.org/tutorial/introduction.html and in particular section 3.1.2 on Strings where you'll find "Degenerate slice indices are handled gracefully: an index that is too large is replaced by the string size, an upper bound smaller than the lower bound returns an empty string." HTH, Emile ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Strings.
On Tue, Oct 23, 2012 at 7:24 PM, Nitin Ainani wrote: > Dear Sir/Madam, > > I am new to python I have a question. It is as follows: > > Suppose s is a variable and s stores empty string > > emptyString = "" #consider the string to be non-empty, that is, let's say 13 characters long (the number you chose below) string13 = "1234567890ABC" print ( string13 [ 0 ] ) >Now if we write following statement > > print ( s [ 0 ] ) # it gives error ***what error? *** The error and your example can be used to understand indexes. s [ 0 ] is asking for the value of a specific piece of s. s[0] is asking for the value at index Zero of string s. S has nothing inside of it. > > print(s[0:])# it does not give error #what does it give? > print (s[13:13]) # this too does not give error #What is the output > why? And with your other two examples I suggest understanding slicing. slice! I want the whole pie, myPie [ 0: ] #the : around an index has a special meaning. Try a string with text and observe the output of your questions. aString [ : ] aString [ : 0 ] aStr [ 1: ] etc Check it out, mess around, get back to me. Alexander ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Strings.
On 10/23/2012 07:48 PM, Alexander wrote: > On Tue, Oct 23, 2012 at 7:24 PM, Nitin Ainani wrote: >> Dear Sir/Madam, >> >> I am new to python I have a question. It is as follows: >> >> Suppose s is a variable and s stores empty string >> >> emptyString = "" > #consider the string to be non-empty, that is, let's say 13 characters > long (the number you chose below) > string13 = "1234567890ABC" > print ( string13 [ 0 ] ) > >> Now if we write following statement >> >> print ( s [ 0 ] ) # it gives error > ***what error? *** > The error and your example can be used to understand indexes. > s [ 0 ] is asking for the value of a specific piece of s. > s[0] is asking for the value at index Zero of string s. > S has nothing inside of it. > >> print(s[0:])# it does not give error > #what does it give? >> print (s[13:13]) # this too does not give error > #What is the output >> why? > And with your other two examples I suggest understanding slicing. > slice! I want the whole pie, myPie [ 0: ] #the : around an index has > a special meaning. > Try a string with text and observe the output of your questions. > aString [ : ] > aString [ : 0 ] > aStr [ 1: ] > > etc > Check it out, mess around, get back to me. > Alexander Nitin: Or even better, stick to the original thread, with the dubious title "Doubt!" What's the point of starting a second nearly-identical thread within 10 minutes? -- DaveA ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Strings.
On 24/10/2012 00:24, Nitin Ainani wrote: Dear Sir/Madam, I am new to python I have a question. It is as follows: Suppose *s* is a variable and *s* stores empty string Pythonistas prefer the use of name and not variable. s="" Now if we write following statement print(s[0]) # it gives error print(s[0:])# it does not give error print (s[13:13]) # this too does not give erro why? This was the design decision made by Guido van Rossum many, many years ago. Other people have already given you other answers on the other thread that you started with the same question but a different subject, please don't do that, thanks. Regards, Nitin -- Cheers. Mark Lawrence. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blackJack problem
> To: tutor@python.org > From: alan.ga...@btinternet.com > Date: Tue, 23 Oct 2012 23:46:23 +0100 > Subject: Re: [Tutor] blackJack problem > > Matthew Dalrymple writes: > > > I thought by having a value outside > > of the functions made the value global. > ok...is there an easier way to write this? the reason i was calling that > global value the same as the currentBet is because i need to add that value > to 5...I have to start at 1000 and if i win add 5 and if i lose subtract 5 > and store that value. I have been staring at this stuff for like 3 hours :/ > and still cant get even a slight idea as of what should work > Not quite. > To change the global value in a function you also need to declare it as > global inside the function. Otherwise it will create a new local > variable that has no effect on the global one. > > Also by declaring a parameter of your function with the same name as the > global you confuse things. Don't do that. > > > Am i somewhat on the right track? > > > > any help would be appriciated... > > > > Oh i also forgot to mention that even though im not using all the parameters > > they have to be there because the professor wants to be able to run other > > peoples "player1.py" files on my game. > > Interesting concept. And if the other peoples files are calling your > functions with values in those parameters you will just ignore them I > presume? Hmmm, that should produce some interesting results... it should work in theory correct? > -- > Alan G > Author of the Learn to Program web site > http://www.alan-g.me.uk/ > Playing with gnus and possibly screwing it up!! > > ___ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blackJack problem
On 24/10/12 01:00, Matthew D wrote: > > I thought by having a value outside > > of the functions made the value global. > ok...is there an easier way to write this? the reason i was calling that global value the same as the currentBet is because i need to add that value to 5... You need to read about global variables and namespaces in Python. But using a global name as a parameter name will not make the function use the global name as the first parameter, in fact the opposite will happen in that the parameter will hide the global value. If you want to pass the global value into your function then call it with the global name as the first argument. If you want to change the global value from your function then you need to declare the name global inside your function: ## readMe = 42 # global var we will read changeMe=666 # global valuer we will change def foo(param1): print param1 print readMe# accesses the global value def bar(): global changeMe # use global value rather than local print 'old: ', changeMe changeMe = 99 print 'new: ', changeMe print readMe, changeMe # print original values foo(readMe) #prints 42 twice, once as param1, once as global value bar() # prints old and new values print readMe, changeMe# print after values ## l...still cant get even a slight idea as of what should work Try the above and variations. If you are still stuck ask here for more detail. You can also try reading the "Whats in a Name?" topic of my tutorial for a different explanation. > > peoples "player1.py" files on my game. > > Interesting concept. And if the other peoples files are calling your > functions with values in those parameters you will just ignore them I > presume? Hmmm, that should produce some interesting results... it should work in theory correct? No, in theory users will get unpredictable results since other people will assume that the values they pass into your functions will influence the result. They will not expect you to ignore them and apply some totally arbitrary values of your own. The theory is that the parameters in a function control the behaviour, not act as simply placeholders for random data. If your teacher wants the function to have certain parameters I suspect he wants you to use them in your function! -- Alan G Author of the Learn to Program web site http://www.alan-g.me.uk/ ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blackJack problem
Thanks Alan Gauld for your help. After taking a little break and coming back it all seemed to make sense...i understand why there is gonna be some really weird outputs to the interchanging of the player1.py files...that really could get interesting LOL...I seemed to have got the program running good now i have only a few pretty simple questions, If you have the GetBet in the player1.py file you have to pass in the total value right?...that is the only way to get the total into the function? the professor told us straight out that he doesnt really know what he is doing...he wanted us to put in (currentBet, previousBet, and win/lose). I think it only makes sense if you put in the total value in as prevousBet. also he wanted us to pass in (player_hand, dealer_hand) in as parameters for the HitStand function...why would we want to total the hand more than once if we already have the total value? wouldn't we want to just pass in those values instead of the hand itself? Im starting to think im not really learning anything from this class...if anything its just confusing me and teaching me the wrong way to go about things thanks again for your help :)> To: tutor@python.org > From: alan.ga...@btinternet.com > Date: Wed, 24 Oct 2012 01:23:30 +0100 > Subject: Re: [Tutor] blackJack problem > > On 24/10/12 01:00, Matthew D wrote: > > > > > I thought by having a value outside > > > > of the functions made the value global. > > > > > ok...is there an easier way to write this? the reason i was calling that > > global value the same as the currentBet is because i need to add that > > value to 5... > > You need to read about global variables and namespaces in Python. > > But using a global name as a parameter name will not make the function > use the global name as the first parameter, in fact the opposite will > happen in that the parameter will hide the global value. > > If you want to pass the global value into your function then call it > with the global name as the first argument. If you want to change the > global value from your function then you need to declare the name global > inside your function: > > ## > readMe = 42 # global var we will read > changeMe=666 # global valuer we will change > > def foo(param1): > print param1 > print readMe# accesses the global value > > def bar(): > global changeMe # use global value rather than local > print 'old: ', changeMe > changeMe = 99 > print 'new: ', changeMe > > print readMe, changeMe # print original values > > foo(readMe) #prints 42 twice, once as param1, once as global value > > bar() # prints old and new values > > print readMe, changeMe# print after values > > ## > > > l...still cant get even a slight idea as of what should work > > Try the above and variations. If you are still stuck ask here for more > detail. > > You can also try reading the "Whats in a Name?" topic of my tutorial for > a different explanation. > > > > > peoples "player1.py" files on my game. > > > > > > Interesting concept. And if the other peoples files are calling your > > > functions with values in those parameters you will just ignore them I > > > presume? Hmmm, that should produce some interesting results... > > it should work in theory correct? > > No, in theory users will get unpredictable results since other people > will assume that the values they pass into your functions will influence > the result. They will not expect you to ignore them and apply some > totally arbitrary values of your own. The theory is that the parameters > in a function control the behaviour, not act as simply placeholders for > random data. If your teacher wants the function to have certain > parameters I suspect he wants you to use them in your function! > > -- > Alan G > Author of the Learn to Program web site > http://www.alan-g.me.uk/ > > ___ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blackJack problem
On Oct 23, 2012, at 11:01 PM, Matthew D wrote: > Thanks Alan Gauld for your help. After taking a little break and coming back > it all seemed to make sense...i understand why there is gonna be some really > weird outputs to the interchanging of the player1.py files...that really > could get interesting LOL...I seemed to have got the program running good > > now i have only a few pretty simple questions, If you have the GetBet in the > player1.py file you have to pass in the total value right?...that is the only > way to get the total into the function? the professor told us straight out > that he doesnt really know what he is doing...he wanted us to put in > (currentBet, previousBet, and win/lose). I think it only makes sense if you > put in the total value in as prevousBet. also he wanted us to pass in > (player_hand, dealer_hand) in as parameters for the HitStand function...why > would we want to total the hand more than once if we already have the total > value? wouldn't we want to just pass in those values instead of the hand > itself? > > Im starting to think im not really learning anything from this class...if > anything its just confusing me and teaching me the wrong way to go about > things > > thanks again for your help :) The best way to learn to program is to program. Doing it in the context of a class has several advantages (even if the prof isn't the sharpest tack in the box)… 1) The class discussion of various approaches to the assignment gives you a range of possible solutions, both good and bad 2) The enforced discipline of generating a solution to the assignment makes you think 3) Learning (almost) any programming language forces you to learn how to reduce a problem to discrete tasks and then steps. Once you've learned ANY language, the next one is easier. That process iterates. 4) Python is an ideal language and environment in which to learn. That is, it's a really good starting place. Just saying… -Bill___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blackJack problem
On 24/10/2012 04:01, Matthew D wrote: big top post snipped. Any chance of your prof teaching you *NOT* to top post and to use plain English while you're at it? -- Cheers. Mark Lawrence. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blackJack problem
> To: tutor@python.org > From: breamore...@yahoo.co.uk > Date: Wed, 24 Oct 2012 04:33:14 +0100 > Subject: Re: [Tutor] blackJack problem > > On 24/10/2012 04:01, Matthew D wrote: > > > > big top post snipped. > > > > wow was this really necessary? no need to be an ass... > Any chance of your prof teaching you *NOT* to top post and to use plain > English while you're at it? > > -- > Cheers. > > Mark Lawrence. > > ___ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blackJack problem
On 24/10/2012 04:36, Matthew D wrote: > To: tutor@python.org From: breamore...@yahoo.co.uk Date: Wed, 24 Oct 2012 04:33:14 +0100 Subject: Re: [Tutor] blackJack problem On 24/10/2012 04:01, Matthew D wrote: big top post snipped. wow was this really necessary? no need to be an ass... If you can't be bothered to check up before you post and you can't write in plain English then yes. -- Cheers. Mark Lawrence. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
