Re: [Tutor] Dictionary blues...
if D.has_key(event.keysym): str=D[event.keysym] self.text.insert(END,str) You can remove the 'text.' thats only used if text were part of a class, which in this case it isn't. Oops, that should say remove 'self.' not text. Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] blocking user access
Diana Hawksworth wrote: Liam, I am using IDLE - and Tkinter, John and Liam. I have been working through the book Python Programming by Michael Dawson. One of his programs calls for the entry of a password, then reveals a message. What I would like to do is make the Text widget that reveals the message, unusable by a user! I tried the state = DISABLED in the 2nd line of code below, where the widget to display the text is created - and it did disable the Text widget - to the extent that it wouldn't reveal the message! I have tried multiple other places to put the DISABLED - at the end of this code for instance, but it doesn't seem to work there! Where can I place it so that it will prevent a user access to that Text widget? Also - assuming I can get it to work - what is the term I need to use to enable to Text widget again so that it will continue to work the next time around. I tried ENABLED - but was told that global name is not defined! Here is a snippet from Fredrik Lundh's An Introduction to Tkinter that shows how to enable the widget, insert some text, then disable it again: text.config(state=NORMAL) text.delete(1.0, END) text.insert(END, text) text.config(state=DISABLED) from http://www.pythonware.com/library/tkinter/introduction/x8309-patterns.htm Kent Any ideas? Thanks in advance for suggestions. Diana Here is the code: # create text widget to display message self.secret_txt = Text(self, width = 35, height = 5, wrap = WORD) self.secret_txt.grid(row = 3, column = 0, columnspan = 2, sticky = W) def reveal(self): Display message based on password. contents = self.pw_ent.get() if contents == secret: message = Here's the secret to living to 100: live to 99 \ and then be VERY careful. else: message = That's not the correct password, so I can't share \ the secret with you. self.secret_txt.delete(0.0, END) self.secret_txt.insert(0.0, message) Hi Diana, Welcome. Are you using IDLE? Could you provide a copy of your code? Regards, Liam Clarke Still a newbie, but not as much. :) On Wed, 23 Mar 2005 20:59:02 +1100, Diana Hawksworth [EMAIL PROTECTED] wrote: Hi! I need help on blocking user access to a message box - for example, the program could provide an answer to an input. At the moment, the user has access to - and can type into - that answer space. How do I prevent that from happening please? Diana - a very newbie! ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor -- 'There is only one basic human right, and that is to do as you damn well please. And with it comes the only basic human duty, to take the consequences. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Mysqldb module - where ?????
I am googling for a slackware package containing the Mysqldb module, but all I am coming up with is MySQLdb. I am not hallucinating right? They are indeed two separate modules? Vicki ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] re question
All I have a string that has a bunch of numbers with the units attached to them. I want to strip off the units. I am using a regular expression and sub to do this. This works great for almost all of the cases. These are the type of lines: SigWind: 857hPa, , 21.0C, 20.1C, 210 @ 9kts SigWind: 850hPa±, , , , 205 @ 11kts Std Lvl: 850hPa, 1503m, 16.8C, 15.7C, 205 @ 11kts I am using the following cleanstring = re.compile( '(hPa|hPa\xb1|m|C|kts)' ). And then the cleanstring.sub(,line). I have tried using numerous \ to escape the \xb1. I also tried replacing all non numeric characters that are part of a number-character string but I could not make that work. The idea was replace all non-number characters in a word that is made up of numbers followed by numbers. I then split the line at the commas so in the current thinking I need the commas for the split. How do I deal with the hPa±? When I print it out it looks like it is a hexadecimal escape character (\xb1) but I am note sure how to deal with this. Any ideas? Thanks ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Changing a class into a subclass
On Mar 24, 2005, at 18:07, Ismael Garrido wrote: Hello. I have a program that saves/loads to/from XML. I have a main class Building, and a subclass House(Building). When I save the code I instruct each object to save itself to XML (using ElementTree), so House adds itself to the XML tree. My problem is when I load the XML. Before having subclasses what I did was to send the XML object (again in ElementTree) to the object and let itself load. Now, with subclasses, if I send the House XML to Building I get a Building instance, when I need a House instance. You can't make an object transform into an object of a different class. You need to identify what class the object will be an instance of before loading it. Which, if you're using XML tags like Building type=House or House, shouldn't be very difficult to do. -- Max maxnoel_fr at yahoo dot fr -- ICQ #85274019 Look at you hacker... A pathetic creature of meat and bone, panting and sweating as you run through my corridors... How can you challenge a perfect, immortal machine? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Changing a class into a subclass
At 10:30 AM 3/24/2005, Max Noel wrote: On Mar 24, 2005, at 18:07, Ismael Garrido wrote: Hello. I have a program that saves/loads to/from XML. I have a main class Building, and a subclass House(Building). When I save the code I instruct each object to save itself to XML (using ElementTree), so House adds itself to the XML tree. My problem is when I load the XML. Before having subclasses what I did was to send the XML object (again in ElementTree) to the object and let itself load. Now, with subclasses, if I send the House XML to Building I get a Building instance, when I need a House instance. You can't make an object transform into an object of a different class Are you referring to a Python object? If so you may assign a class to the object's __class__ attribute. class A:pass class B:pass b = b() print b.__class__ # displays class __main__.B at 0x011BB9C0 b.__class__ = A print b.__class__ # displays class __main__.A at 0x011BBA20 [snip] Bob Gailer mailto:[EMAIL PROTECTED] 510 558 3275 home 720 938 2625 cell ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] I need some guidance
Alan, I am a bit lost when you wrote: Read a lot and experiment a lot. Thats where Pythons prompt really helps. You can build quite sophisticated programs very quickly by the way Windows XP and the Python v2.4). Do you mean writing from the Command Line windows instead to use the IDLE one? No, I mean any prompt whether in IDLE or the command line. The point is, you can experiment at the prompt before typing the code into a file. Calling a function lots of times with different values for example is a great way to learn how to use it, and much faster than writing a full program, saving it, then running it and then changing it, and repeating. Just type the command in at the prompt and hit Enter. Then hit up arrow or CTRL P to bring the line back, change the values and hit Enter again... Once you've got it just how you want it, type the line into a real program. That's still how I get to grips with any new modules that I haven't used before. HTH, Alan G Author of the Learn to Program web tutor http://www.freenetpages.co.uk/hp/alan.gauld ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Changing a class into a subclass
let itself load. Now, with subclasses, if I send the House XML to Building I get a Building instance, when I need a House instance. You can't make an object transform into an object of a different class. You need to identify what class the object will be an instance of before loading it. Which, if you're using XML tags like Building type=House or House, shouldn't be very difficult to do. Absolutely, looks like you answered your own question... :-) But if you want an OOP approach thre are some things to try. First you can create a BuildingFactory class that has a single instance (or indeed no instances because you could use a static method... or get really fancy and create a meta-class!). The factory class then takes the XML string fragment and figures out which subclass of Building to create and returns the required object. You can avoid having to recode the factory class each time by using a dictionary object and each subclass definition adds an entry to the Factory class dictionary - possibly by calling a class method of Building in the __init__() code class Shack(Building): def __init__(self,p1,p2...): Building.__init__(self,...) Building.register(self,'Shack', Shack) ...rest of init... Now the factory code can go name = self.getClassName(xmlString) obj = self.classList[name]() and instantiate a Shack object. But unless you expect to create an awful lot of subclasses, or just want to be purist in approach its probably overkill! Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Changing a class into a subclass
Are you referring to a Python object? If so you may assign a class to the object's __class__ attribute. class A:pass class B:pass b = b() print b.__class__ # displays class __main__.B at 0x011BB9C0 b.__class__ = A print b.__class__ # displays class __main__.A at 0x011BBA20 Interesting Bob, but presumably that doesn't change the internal state so the OP would need to run an initialise method using the XML? Or no, I suppose if he did this inside the class's init method, as the first step, it would then initialise as usual? I feel a spell at the coming on... The problem is you still need to identify the class itself (not the class name) before you can do this, but I guess you might get that from either the builtins dictionary or the Building module if it has all the Building subclasses in? But it certainly does allow you to 'convert' from one class to another, much like the C++ cast operator. Alan g. Learning something new every day. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Changing a class into a subclass
Alan Gauld wrote:
But if you want an OOP approach thre are some things to try.
First you can create a BuildingFactory class that has a
single instance (or indeed no instances because you could
use a static method... or get really fancy and create a
meta-class!).
or make it a static method of Building or get really simple and use a
module-level function...
The factory class then takes the XML string
fragment and figures out which subclass of Building to
create and returns the required object. You can avoid
having to recode the factory class each time by using a
dictionary object and each subclass definition adds an entry
to the Factory class dictionary - possibly by calling a
class method of Building in the __init__() code
class Shack(Building):
def __init__(self,p1,p2...):
Building.__init__(self,...)
Building.register(self,'Shack', Shack)
...rest of init...
I think you want to register Shack before you ever create one. You could do
it after Shack is defined:
class Shack(Building):
def __init__(self,p1,p2...):
Building.__init__(self,...)
...rest of init...
Building.register('Shack', Shack)
or you could probably get tricky and do it in a metaclass...but I'm not that
tricky.
Kent
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[Tutor] Defining functions
Hi there, I have written (well almost as I copied some lines from an existing example) this little programme - part of an exercise. #By J Carmona #Programme that compute area for #circle, square, rectangle def area_rect(): length = input(Length: ) width = input (Width: ) print The area is: ,length*width def area_circ(): radius = input(What is the radius?: ) print The area is approximately: , 3.14159*(radius**2) def area_squ(): side = input (What is the length of one side?: ) print The area is: , side*side def print_options(): print -- print Options: print 1. print options print 2. calculate circle area print 3. calculate square area print 4. calculate rectangle area print 5. quit the programme print -- choice = input(Choose an option: ) if choice == 1: print_options() elif choice == 2: area_circ() elif choice == 3: area_squ() elif choice == 4: area_rect() elif choice == 5: print_options() #Call starting menu print_options() If I try to change the 1, 2, 3, 4 or 5 by a letter i.e. a, b, c, d, e the programme stop functionning. I get an error message saying that Traceback (most recent call last): File C:/Python24/Example/area_cir_squ_regt.py, line 39, in -toplevel- print_options() File C:/Python24/Example/area_cir_squ_regt.py, line 27, in print_options choice = input(Choose an option: ) File string, line 0, in -toplevel- NameError: name 'c' is not defined What am I missing? Thanks JC ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Defining functions
John Carmona wrote:
Hi there,
I have written (well almost as I copied some lines from an existing
example) this little programme - part of an exercise.
def print_options():
print --
print Options:
print 1. print options
print 2. calculate circle area
print 3. calculate square area
print 4. calculate rectangle area
print 5. quit the programme
print --
choice = input(Choose an option: )
if choice == 1:
print_options()
elif choice == 2:
area_circ()
elif choice == 3:
area_squ()
elif choice == 4:
area_rect()
elif choice == 5:
print_options()
If I try to change the 1, 2, 3, 4 or 5 by a letter i.e. a, b, c, d, e
the programme stop functionning. I get an error message saying that
Traceback (most recent call last):
File C:/Python24/Example/area_cir_squ_regt.py, line 39, in -toplevel-
print_options()
File C:/Python24/Example/area_cir_squ_regt.py, line 27, in print_options
choice = input(Choose an option: )
File string, line 0, in -toplevel-
NameError: name 'c' is not defined
The input() function evaluates the input as if it is Python code. So you can type 1+2 to input and
it will return 3, for example:
print input('type a valid expression: ')
type a valid expression: 1+2
3
If you type a bare string, Python expects this to be a variable name:
print input('type a valid expression: ')
type a valid expression: a
Traceback (most recent call last):
File stdin, line 1, in ?
File string, line 0, in ?
NameError: name 'a' is not defined
This is exactly the same error you would get if you just typed a bare 'a' at
the interpreter prompt:
a
Traceback (most recent call last):
File stdin, line 1, in ?
NameError: name 'a' is not defined
To get a string from input(), you have to type it with quotes:
print input('type a valid expression: ')
type a valid expression: 'abcd'
abcd
raw_input() will return the literal string the user typed. If you input is a string, this is what
you want:
print raw_input('type anything: ')
type anything: 1+2
1+2
print raw_input('type anything: ')
type anything: abcd
abcd
In general, raw_input() is safer than input(), which is vulnerable to abuse. Even if you want an
integer input, you can use raw_input() and int():
print int(raw_input('type a number: '))
type a number: 35
35
Kent
PS you do need to quote the letters in your if / elif also.
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[Tutor] Re: xmlrpc server
Luis N wrote on Thu, 24 Mar 2005 05:31:03 +0200: snip py-xmlrpc uses a scant 4mb of memory, does only one thing, and does it well, serve xmlrpc requests. It appears significantly faster than Twisted. SimpleXMLRPCServer, as a CGI solution, appears acceptable, given that it be run from FastCGI or mod_python to give it that extra boost. Unless you are aware right now of certain limitations which make one of the solutions a priori unusable for whatever you want to do, I'd say just go with the one which you find easiest to use and try to code in such a way that it's reasonably easy to replace it with something else later. For example 20 MB memory use doesn't sound like much to me on a modern computer, but I'd leave Nevow out of the choice of your XMLRPC server. -- Yours, Andrei = 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. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Changing a class into a subclass
Alan Gauld wrote: Absolutely, looks like you answered your own question... :-) But if you want an OOP approach thre are some things to try. First you can create a BuildingFactory class that has a single instance (or indeed no instances because you could use a static method... or get really fancy and create a meta-class!). The factory class then takes the XML string fragment and figures out which subclass of Building to create and returns the required object. You can avoid having to recode the factory class each time by using a dictionary object and each subclass definition adds an entry to the Factory class dictionary - possibly by calling a class method of Building in the __init__() code My current aproach is something like that. I subclassed Building(Building) :-) and wrote there the factory which returns self of the created instance. But that didn't go with all my other classes that have, as a design rule, that they manage the loading and saving from/to XML. That meant that Building was different to the other classes, and instead of doing: a = Ship() a.fromXML(xml) listOfA.append(a) I had to do: a = Building() listOfBuildings.append(a.fromXML(xml)) When I wrote my factory I thought about the dictionary approach, but I didn't write it because I hoped I could find something like the __class__ thing. Which, btw, is pure magic :-) But there's something that I couldn't understand. In the following code, my guess would be that I'm back from the death would never get printed... but it is... and twice! Why? class A: def pong(self): print self.__class__ print Ping! self.times -=1 if self.times = 0: self.__class__ = B self.pong() class B: def pong(self): print self.__class__ print Pong! self.times -=1 self.__class__ = A self.pong() print I'm back from the death a = A() a.times = 3 a.pong() __main__.A Ping! __main__.B Pong! __main__.A Ping! __main__.B Pong! __main__.A Ping! I'm back from the death ##Weird! I'm back from the death a.__class__ class __main__.A at 0x00C1AF00 Thanks, Ismael ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Changing a class into a subclass
Ismael Garrido wrote: But there's something that I couldn't understand. In the following code, my guess would be that I'm back from the death would never get printed... but it is... and twice! Why? It's printed every time B.pong() is called, just as Pong is. You print each one twice - no mystery! Kent class A: def pong(self): print self.__class__ print Ping! self.times -=1 if self.times = 0: self.__class__ = B self.pong() class B: def pong(self): print self.__class__ print Pong! self.times -=1 self.__class__ = A self.pong() print I'm back from the death a = A() a.times = 3 a.pong() __main__.A Ping! __main__.B Pong! __main__.A Ping! __main__.B Pong! __main__.A Ping! I'm back from the death ##Weird! I'm back from the death a.__class__ class __main__.A at 0x00C1AF00 Thanks, Ismael ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Trying to use MySQLdb.cursor
I finally gave up and used MySQLdb to connect to my database. It connects okay, and returns data, but now I have a new question. I use the code below to print the data returned from my query, but I would like to make labels at the top of the columns. How do I do this dynamically? I would like to get the fieldnames as defined by mysql and print them before printing each column. Is there a way to do this? Here is the relevant portion of the code: def getdata(): conn = MySQLdb.Connect( host='localhost', user='user', passwd='password', db='sample',compress=1, cursorclass=MySQLdb.cursors.DictCursor) cursor = conn.cursor() cursor.execute(SELECT computers.comp_location FROM computers, mice WHERE mice.mouse_type = USB AND computers.comp_location like A% AND mice.mouse_comp = computers.comp_id;) rows = cursor.fetchall() cursor.close() conn.close() print ''' table border=1 cellpadding=5 ''' for row in rows: print tr for cell in row: print td %s /td % row[cell] print /tr Thanks for helping me get going. Vicki ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Trying to use MySQLdb.cursor
On Fri, 25 Mar 2005, Vicki Stanfield wrote:
I finally gave up and used MySQLdb to connect to my database. It
connects okay, and returns data, but now I have a new question. I use
the code below to print the data returned from my query, but I would
like to make labels at the top of the columns. How do I do this
dynamically?
Hi Vicki,
Yes, there's a special cursor type that, instead of returning rows of
tuples, returns rows of dictionaries. Here's an example:
##
import MySQLdb
import MySQLdb.cursors
conn = MySQLdb.connect(db='test_adb',
...cursorclass=MySQLdb.cursors.DictCursor)
cursor = conn.cursor()
cursor.execute(select * from Locus limit 10)
10L
cursor.fetchone()
{'orientation_is_5': 1, 'last_updated': DateTime object for '2005-03-24
13:48:06.00' at 402faad8, 'is_deleted': 0, 'name': 'At1g08520',
'representative_model': None, 'is_pseudogene': 0, 'last_updated_by': 1L,
'assigned_to': None, 'update_needed': None, 'gene_model_type': 0L, 'id':
1L, 'chromosome': 1L, 'locked_for_pasa': 0}
##
Hmmm.. that's a little messy. Let me clean up the output of that a bit
with the pretty printing module 'pprint':
##
import pprint
pprint.pprint(cursor.fetchone())
{'assigned_to': None,
'chromosome': 1L,
'gene_model_type': 0L,
'id': 2L,
'is_deleted': 0,
'is_pseudogene': 0,
'last_updated': DateTime object for '2005-03-24 13:48:02.00' at
403104b8,
'last_updated_by': 1L,
'locked_for_pasa': 0,
'name': 'At1g08530',
'orientation_is_5': 1,
'representative_model': None,
'update_needed': None}
##
The output's content itself is probably a bit bizarre to you (It's a gene
from the Arabidopsis plant database) But I hope the code is clear.
*grin*
If you have more questions, please feel free to ask!
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Re: [Tutor] Getting file sizes (fwd) [oops, old message!]
Hi everyone, My apologies about the repeated message; I just got an old message from last year, and didn't look closely enough to see that it was a repeat from last year! The mail queue of some folks is really ancient; I wonder why that bounced to me today. Odd. Anyway, sorry about that! ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
