Re: [Tutor] Code Readability (was: Recursion and List Comprehensions)
Since when is elegance a dirty word? Elegance is the soul of good programming. A simple and graceful solution to the widest number of cases, efficient and easy to understand in application. Sometimes subtle, but always beautiful. In language design, software architecture, algorithms, it is the rushing light of clarity that banishes dark and smelly corners. It's side effects are many--reusable code, effortless speed, painless maintenance, reduced complexity. The dreams shared by physicists, mathematicians, and engineers, are dreams of elegance. It is heartbreaking to see a concise and useful term maligned by dense one-liners, which are seldom anything except hard to read. Simple and short ain't the same thing. And having indulged in possibly very off-topic interlude, let me point out that recognizing a donut when you see it, doesn't make you a baker. Trust me, I'm not baking donuts. And judging by the amount of Escher-like pretzels that continute to be baked in the world, we have a long ways to go before we get more than the occasional sighting or passing whiff of something sweet and round with a hole in the middle. . Take care, Andrew On 10/28/05, Carroll, Barry <[EMAIL PROTECTED]> wrote: > Kent Johnson <[EMAIL PROTECTED]> wrote: > > <> > > >>PS Don't get too crazy about eliminating intermediate variables, they can > >>make the code more readable. > >> > >>Kent > > I agree. When writing for keeps (i.e. production code) I prefer clarity and > ease of maintenance over 'elegance' or 'trickiness'. This exercise is > intended, in part, to sharpen my understanding of Python idioms. If I can > write highly idiomatic code that works, chances are better that I will be > able to decipher it when I come across it elsewhere. > > Barry > > > ___ > 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] Tkinter
When I run the following code,
script kept running and I have to force it to stop.
Could you check the code to give suggestions how to improve it?
Thanks a lot!
from Tkinter import *
from Tkinter import _cnfmerge
class Dialog(Widget):
def __init__(self, master=None, cnf={}, **kw):
cnf = _cnfmerge((cnf, kw))
self.widgetName = '__dialog__'
Widget._setup(self, master, cnf)
self.num = self.tk.getint(
apply(self.tk.call,
('tk_dialog', self._w,
cnf['title'], cnf['text'],
cnf['bitmap'], cnf['default'])
+ cnf['strings']))
try: Widget.destroy(self)
except TclError: pass
def destroy(self): pass
if __name__ == '__main__':
q = Button(None, {'text': 'How are you',
Pack: {}})
b1 = Listbox()
b1.pack()
c1 = Checkbutton(text="Check")
c1.pack()
q.mainloop()
from Tkinter import *
root =Tk()
menu=Menu(root)
root.config(menu=menu)
filemenu=Menu(menu)
menu.add_cascade(label="Test", menu=filemenu)
filemenu.add_command(label="Just Try")
filemenu.add_separator()
mainloop()
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Re: [Tutor] Tkinter
What kind of improvement you looking for?
On 10/29/05, Shi Mu <[EMAIL PROTECTED]> wrote:
> When I run the following code,
> script kept running and I have to force it to stop.
> Could you check the code to give suggestions how to improve it?
> Thanks a lot!
>
> from Tkinter import *
> from Tkinter import _cnfmerge
>
> class Dialog(Widget):
> def __init__(self, master=None, cnf={}, **kw):
> cnf = _cnfmerge((cnf, kw))
> self.widgetName = '__dialog__'
> Widget._setup(self, master, cnf)
> self.num = self.tk.getint(
> apply(self.tk.call,
> ('tk_dialog', self._w,
> cnf['title'], cnf['text'],
> cnf['bitmap'], cnf['default'])
> + cnf['strings']))
> try: Widget.destroy(self)
> except TclError: pass
> def destroy(self): pass
>
> if __name__ == '__main__':
>
> q = Button(None, {'text': 'How are you',
> Pack: {}})
> b1 = Listbox()
> b1.pack()
>
> c1 = Checkbutton(text="Check")
> c1.pack()
>
> q.mainloop()
>
> from Tkinter import *
> root =Tk()
> menu=Menu(root)
> root.config(menu=menu)
> filemenu=Menu(menu)
> menu.add_cascade(label="Test", menu=filemenu)
> filemenu.add_command(label="Just Try")
> filemenu.add_separator()
> mainloop()
> ___
> Tutor maillist - Tutor@python.org
> http://mail.python.org/mailman/listinfo/tutor
>
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Re: [Tutor] Tkinter
move the bottom codes to the top and try to make
the codes following if __name__ == '__main__':
as few as possible.
also,
i want the main menu come first, and after clicking test/just try, i
can go to the "how are you" interface.
On 10/29/05, Liam Clarke <[EMAIL PROTECTED]> wrote:
> What kind of improvement you looking for?
>
> On 10/29/05, Shi Mu <[EMAIL PROTECTED]> wrote:
> > When I run the following code,
> > script kept running and I have to force it to stop.
> > Could you check the code to give suggestions how to improve it?
> > Thanks a lot!
> >
> > from Tkinter import *
> > from Tkinter import _cnfmerge
> >
> > class Dialog(Widget):
> > def __init__(self, master=None, cnf={}, **kw):
> > cnf = _cnfmerge((cnf, kw))
> > self.widgetName = '__dialog__'
> > Widget._setup(self, master, cnf)
> > self.num = self.tk.getint(
> > apply(self.tk.call,
> > ('tk_dialog', self._w,
> > cnf['title'], cnf['text'],
> > cnf['bitmap'], cnf['default'])
> > + cnf['strings']))
> > try: Widget.destroy(self)
> > except TclError: pass
> > def destroy(self): pass
> >
> > if __name__ == '__main__':
> >
> > q = Button(None, {'text': 'How are you',
> > Pack: {}})
> > b1 = Listbox()
> > b1.pack()
> >
> > c1 = Checkbutton(text="Check")
> > c1.pack()
> >
> > q.mainloop()
> >
> > from Tkinter import *
> > root =Tk()
> > menu=Menu(root)
> > root.config(menu=menu)
> > filemenu=Menu(menu)
> > menu.add_cascade(label="Test", menu=filemenu)
> > filemenu.add_command(label="Just Try")
> > filemenu.add_separator()
> > mainloop()
> > ___
> > Tutor maillist - Tutor@python.org
> > http://mail.python.org/mailman/listinfo/tutor
> >
> ___
> Tutor maillist - Tutor@python.org
> http://mail.python.org/mailman/listinfo/tutor
>
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[Tutor] threaded chat server, is this the way?
Hi,
Im trying to write a threaded chat server, building on examples given in
the book "Python Network Programming", chapter 21.
I have managed to come up with af working (so it seems) solution, see
code below.
My question is: What is wrong with this aproach?
I put each new connection in a common dict, and when i recieve a message
i loop the dict and send the message to each connection (except the sender).
In the book I'm told I have to a semaphore and a queue for each
connection. What would I achieve by doing this, and how would i go about it?
Thanks
Christian
My code looks like this:
--
# -*- coding: latin_1 -*-
# original: Echo Server with Threading - Chapter 21 - echoserver.py,
Python Network programming
import socket, traceback, os, sys
from threading import *
import time
host = '' # Bind to all interfaces
port = 1
def handleclient(clientsock, connectionsDic):
print "New child", currentThread().getName()
print "Got connection from", clientsock.getpeername()
#assign a name to this connection and put it in connectionsDic
name = currentThread().getName()
connectionsDic[name]=clientsock
buffer = ""
try:
while 1:
input = clientsock.recv(4096)
if not len(input):
break
buffer += input
if "\n" in buffer:
#todo: check that \n is actually the end of buffer
data = buffer
buffer =""
for connName in connectionsDic.keys():
message = "%s says: %s"%(name, data)
try:
if connName!=name:
connectionsDic[connName].sendall(message)
else:
connectionsDic[connName].sendall("Your
message has been passed on\n\r")
except:
pass
finally:
# Close the connection
clientsock.close()
del connectionsDic[name]
print name, " says goodbye.."
# Set up the socket.
s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
s.bind((host, port))
s.listen(1)
#Dict to keep track og connections
connectionsDic = {}
while 1:
try:
clientsock, clientaddr = s.accept()
except KeyboardInterrupt:
raise
except:
traceback.print_exc()
continue
t = Thread(target = handleclient, args = [clientsock, connectionsDic])
t.setDaemon(1)
t.start()
---
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[Tutor] Nokia 60 series
There's some extra info here: http://comments.gmane.org/gmane.comp.python.announce/5658 HTH, Matt -- Dr. M. Williams MRCP(UK) Clinical Research Fellow Cancer Research UK +44 (0)207 269 2953 +44 (0)7834 899570 http://acl.icnet.uk/~mw http://adhominem.blogspot.com ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Tkinter
> When I run the following code,
> script kept running and I have to force it to stop.
Yep. Thats usually what happens when you run a GUI program.
What did you expect it to do?
> Could you check the code to give suggestions how to improve it?
I'll add some comments but its not clear what you are trying to do.
Some general points first:
1) You should only have one call to mainloop() in a Tkinter program.
2) Its bad practice to have code after the "if name==main " block.
That code gets exercised as well as the if block - very confusing!
Specific comments:
class Dialog(Widget):
def __init__(self, master=None, cnf={}, **kw):
cnf = _cnfmerge((cnf, kw))
self.widgetName = '__dialog__'
AG> Looks a bit weird. Names starting with underscores usually mean private
AG> and __xxx___ style names are usually private to Python itself... But
those are
AG> merely conventions, but useful ones...
Widget._setup(self, master, cnf)
AG> Are you sure you don't want to call Widget.__init__ first?
self.num = self.tk.getint(
apply(self.tk.call,
('tk_dialog', self._w,
cnf['title'], cnf['text'],
cnf['bitmap'], cnf['default'])
+ cnf['strings']))
AG> I have no idea whats going on here! Can you explain?
try: Widget.destroy(self)
except TclError: pass
AG> And having constructed the Widget subclass you now destroy it?
AG> I'm very confused.
def destroy(self): pass
AG> except destroy doesn't do anything...
if __name__ == '__main__':
q = Button(None, {'text': 'How are you',
Pack: {}})
AG> This is a very old fashioned way of configuring a Tkinter widget
AG> and suggests you have been looking at a very old Tkinter tutorial.
q = Button(None, text="How are you")
q.pack()
AG> would be more common.
b1 = Listbox()
b1.pack()
c1 = Checkbutton(text="Check")
c1.pack()
q.mainloop()
AG> So you set the mainlop running here and wait for events.
AG> But you haven't defined any event handlers anywhere
AG> let alone connected them to your widgets. The only things
AG> that will work are the default window widgets
from Tkinter import *
AG> You've already done this up top
root =Tk()
menu=Menu(root)
root.config(menu=menu)
filemenu=Menu(menu)
menu.add_cascade(label="Test", menu=filemenu)
filemenu.add_command(label="Just Try")
filemenu.add_separator()
AG:> And this all looks a bit confused too, I'm not sure what
AG> you are trying to achieve here?
mainloop()
AG> And you already called mainloop above, although this mainlop isn't
AG> defined anyplace that I can see, its nopt attached to an object of
AG> any kind...
I think you need to clarify in your mind what you are trying to achieve
and restructure the code to reflect that. As it is its not clear what
exactly
you think the code should do.
Can you simplify it? Just get a basic window/menu combination set up
and working, then once thats fixed fold the config stuff in later?
Also I'd make sure you check out the latest Tkinter tutorial, all that
configuration by dictionary stuff was deprecated about 7 years ago!
HTH,
Alan G
Author of the learn to program web tutor
http://www.freenetpages.co.uk/hp/alan.gauld
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[Tutor] OS X 10.4 and MySQL for Python
I was just about to attempt to install the python mysql package (http://sourceforge.net/projects/mysql-python/). I just wanted to know if anyone has attempted this on OS X 10.4. Searching the list it is very possible on past versions of os x no one seems to have commented on the latest version though. Cheers Eddie. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Global var problem
Alan Gauld wrote: >> messing about with classes I've come across something basic that I >> don't understand. > > > As you say this has nothing to do with classes its more basic. Its > about namespaces. Try reading the namespaces topic in my tutor for > more info. > > Meanwhile lets simplify by removing the class bit > > > def h(): > global x > x += 1 > print x > > h() # prints 43 Many thanks to Alan, Andrei, Hugo and Welsey for helping me to understand where I was going wrong. I thought I understood namespaces but _obviously_ not . Thanks again, Nick . ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Can anyone help me?
Title: Message The "odds" are determined by the number of favorable outcomes to the number of unfavorable outcomes. In the case of flipping a coin, the odds are 1/1 (sometimes written as 1:1) for heads. The _probability_ of an event (as per a "frequency" definition) is the number of favorable outcomes that cause the event to occur to the total number of outcomes (assuming a uniform distribution). For flipping a coin, the probability of heads would be 1/2. Whether or not the total number of tickets sold impacts your probability of winning depends on the way that the lottery is conducted. Here in Georgia, I believe that the winning lottery sequence is drawn from all possile sequences, not from the restricted set of those sequences from sold tickets only. In the former case, the probability of winning is dependent only on the number of tickets you purchase. In the latter case (or a similar case in which winning sequences were generated until someone won), the number of other tickets sold would affect your chances of winning. -Nick Pomponio From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Smith, JeffSent: Friday, October 28, 2005 11:08 AMTo: bob; Tutor@python.orgSubject: Re: [Tutor] Can anyone help me? But the odds that you will win are not impacted by the number of tickets that are sold in total...only the number you buy. When you take into account the total number of tickets sold, all you get are the odds that the lottery will be won by anyone. I'm also a little confused by that def of odds. Consider flipping a coin. The probability that it will come up heads is 1/2. That def says that the odds in favor of it coming up heads is 1. Jeff -Original Message-From: bob [mailto:[EMAIL PROTECTED] Sent: Friday, October 28, 2005 10:52 AMTo: Smith, Jeff; Tutor@python.orgSubject: Re: [Tutor] Can anyone help me?At 07:28 AM 10/28/2005, Smith, Jeff wrote: Aren't the odds just based on how many tickets you buy? The odds aren'taffected by different people buying more tickets. If only one personbuys a ticket in the entire lottery system, his odds of winning are thesame as if two people play, and the same as if 20 million play.According to the wikipedia: "In probability theory and statistics the odds in favor of an event or a proposition are the quantity p / (1-p), where p is the probability of the event or proposition." If you assign equal probability of winning to each ticket then odds are how many tickets you buy relative to how many tickets everyone else has bought. The probability of a ticket winning is 1 / m**n where m is the highest number possible and n is the number of numbers. If a lottery uses 6 numbers each in the range 1..42 then the probability of a ticket winning is 1/5489031744. All of this is mathematics. Sometimes one or more tickets win. Is that "luck"? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Real newbie - python can't open spam.py
Hi I'm on my first day with python2.3 on Windows XP. I'm able to run python interactively. I've created a text file using NotePad, named it spam.py (as per O'REILLY Learning Python, p13) contents as folows import sys print sys.argv If I do: >python spam.py it says can't open file 'spam.py' Anyone know why? I can open the file in NotePad without problem. Thanks Mike ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Real newbie - python can't open spam.py
Michael Rowan wrote: > Hi > > I'm on my first day with python2.3 on Windows XP. I'm able to run > python interactively. > > I've created a text file using NotePad, named it spam.py. If I do: > > >python spam.py > > it says can't open file 'spam.py' > > Anyone know why? I can open the file in NotePad without problem. Is spam.py in the current directory when you type the command? If not, cd to the directory containing spam.py. What is the exact error message you get? Kent -- http://www.kentsjohnson.com ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] IDLE error msgs and line continuations?
On Thu, 27 Oct 2005, CPIM Ronin wrote: > When using IDLE, after hitting F5 to save and run, if an error occurs, > it merely flashes at the code location of the error. While I usually > figure out what is wrong, why don't I get the detailed text error > messages that the command line gives? > > Also, I'm getting most error messages when I try line continuation for > clarity: > > if (condition 123 and > condition 456): Hi RC, It might be the case that 'condition 123' is malformed. If this is true, then the problem doesn't stem from going across lines, but with the 'condition 123' and 'condition 456' stuff. Just to check: ## >>> if (condition 123 and File "", line 1 if (condition 123 and ^ SyntaxError: invalid syntax ## Yeah, looks like Python immediately seizes on that part and stops at the point where the SyntaxError is. It doesn't even wait for me to enter in the rest of the line. I'm not sure if this is the real error that you're seeing; you may have just used 'condition 123' simply as an example. If you have code that you can show us, we'll look at it more carefully. Best of wishes to you! ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Birthday paradox (was: Re: Random number generator (was: Can anyone help me?))
On Fri, 28 Oct 2005, Johan Geldenhuys wrote:
> After I tested the previous code, I noticed that the odds is 1:49 that a
> duplicate number can be found in the 6 digit range (and it happended)
> and that 0 can also be found.
Hi Johan,
I'm not exactly sure how 1 in 49 are the odds of getting a duplication.
Let's talk about this for a moment.
[Warning: long post ahead.]
Just to make sure: the situation is that we're rolling a fifty-sided dice
six times, and we'd like to see what's the probability of having
duplicates in the mix. We have 50**6 possible rolls, but there are only:
50 * 49 * 48 * 47 * 46 * 45
ways of making sure we don't hit duplicates. The probability that we
don't hit any duplicates, then, is:
##
>>> (50 * 49 * 48 * 47 * 46 * 45) / (50 **6)
0L
#
Oops, forgot about integer division. *grin*
Let me try that again:
##
>>> (50.0 * 49 * 48 * 47 * 46 * 45) / (50 **6)
0.7322434559996
##
Ok, so we have about a 73% chance of not having any duplicate numbers if
we roll a 50-digit dice six times.
Since we can either have no duplication or duplication, then he
probability that we will have duplication is:
(1 - probability of not having duplication)
##
>>> 1 - (50.0 * 49 * 48 * 47 * 46 * 45) / (50 **6)
0.2677565440004
##
So we have about a 27% percent chance of getting duplication when we roll
a fifty sided dice six times.
But that's just probability theory. Is this real? Is this truly
probable?
Let's test this experimentally. First, we need some way of generating a
roll of dice. Here's a quick-and-dirty function to do that:
##
>>> def make_roll(n, r):
... return [random.randrange(n) for i in range(r)]
...
>>> make_roll(50, 6)
[11, 48, 39, 43, 30, 24]
>>> make_roll(50, 6)
[6, 47, 0, 34, 9, 38]
##
We can test things experimentally by writing a function to see a roll has
duplication:
##
>>> def has_duplication(roll):
... d = {}
... for number in roll:
... d[number] = d.get(number, 0) + 1
... for count in d.values():
... if count > 1:
... return True
... return False
...
>>> has_duplication([1, 2, 3])
False
>>> has_duplication([1, 2, 2])
True
##
Once we have this tool, then it becomes easy to do a trial run and see, if
we roll 10 times, what percentage of those are duplicates.
##
>>> count_duplicates = 0
>>> for i in range(10):
... if has_duplication(make_roll(50, 6)):
... count_duplicates = count_duplicates + 1
...
>>> count_duplicates
1
>>> 1.0 / 10
0.10001
##
Experimentally, we're seeing 1%, but that might just be a fluke. Or maybe
it's just because the trial size is much too small. *grin*
Let's formalize this test as a function, just to make it easier to retry:
##
>>> def do_trial(n):
... """Returns the number of duplicates if we do a n-trial."""
... count_duplicates = 0
... for i in range(n):
... if has_duplication(make_roll(50, 6)):
... count_duplicates = count_duplicates + 1
... return float(count_duplicates) / n
...
>>>
>>> do_trial(5)
0.40002
>>> do_trial(10)
0.2
>>> do_trial(100)
0.27002
>>> do_trial(1000)
0.26902
>>> do_trial(1)
0.2621
>>> do_trial(10)
0.26676
##
So we're experimentally getting evidence that the probability of rolling
duplicates is about 26%, if we have a 50-sided dice six times. Hey,
that's not bad: that's about the value we got from doing math.
As we scale our expeiment higher, we start seeing the Law of Large Numbers
taking place: when we use lots of trials, then our experimental results
start getting very close to the one we calculated with probability theory.
http://en.wikipedia.org/wiki/Law_of_large_numbers
Here's a punchline: the problem we've been looking at is another disguise
for the Birthday Paradox:
http://en.wikipedia.org/wiki/Birthday_problem
That article makes the assertion that if we have 23 people in a room, the
probability that we have at least two people with the same birthday is
pretty good (about 50%). We can modify do_trial() to experimentally see
that!
##
>>> def do_trial(n, x, y):
... """Returns the number of duplicates if we do a n-trial."""
... count_duplicates = 0
... for i in range(n):
... if has_duplication(make_roll(x, y)):
... count_duplicates = count_duplicates + 1
... return float(count_duplicates) / n
...
>>> do_trial(1, 365, 23)
0.51392
>>> do_trial(1, 365, 1)
0.0
>>> do_trial(1, 365, 2)
0.0023
>>> for i in range(23):
... print i, "people, probability of shared birthday:",
do_trial(1, 365, i)
...
0 people, probability of shared birthday: 0.0
1 people, probability of shared birthday: 0.0
2 people, probability of shared birthday: 0.0035
3 people, probability of shared birthday: 0.0087
4 people, probability of shared birthday: 0.0181
5 people, probability of shared birthday: 0.0273
Re: [Tutor] Birthday paradox (was: Re: Random number generator (was: Can anyone help me?))
> ## > >>> count_duplicates = 0 > >>> for i in range(10): > ... if has_duplication(make_roll(50, 6)): > ... count_duplicates = count_duplicates + 1 > ... > >>> count_duplicates > 1 > >>> 1.0 / 10 > 0.10001 > ## > > > Experimentally, we're seeing 1%, but that might just be a fluke. Or maybe > it's just because the trial size is much too small. *grin* Gaaa. I can't add or subtract. I meant: Experimentally, we're seeing 10%, but that might just be a fluke. Or maybe it's just because the trial size is much too small. > >>> def do_trial(n): > ... """Returns the number of duplicates if we do a n-trial.""" > ... count_duplicates = 0 > ... for i in range(n): > ... if has_duplication(make_roll(50, 6)): > ... count_duplicates = count_duplicates + 1 > ... return float(count_duplicates) / n The comment is wrong. It should be: """Returns the probability of duplicates if we do an n-trial.""" > The variable names 'x' and 'y' suck (I'll try to think of better ones next > time), but I hope that it's clear what we're doing: we're making > do_trial() more general so it can handle different dice rolls. And > because they are parameters in our do_trial() function, we can then see > what the situation loosk like as we get more and more kids in the ^ Looks, not loosks. Sorry about that! ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Python as Application (OT now)
Sorry about misposting this here. I always mix up the
tutor@ and edu-sig@ lists. I am just going to follow
up two things that seem tutor related.
If this seems interesting, you may want to join the
edu-sig list for more...
>>More frightening to me than the ubiquitous use of MS Office is the
>>omnipresence of windows. Every time a student sits down in front
>>of KDE in our lab and says "Where is the internet?" I can only cringe.
>I do wonder why you cringe. Educate the user. He is expecting his
>usual metaphor, and it's not there. The majority of the world has it,
>remember, so he expects you to as well.
>
Certainly. I guess I should have said "I have to cringe" instead of
"...only cringe". I don't just walk away and leave people wondering
why it is impossible to do what they want to do.
As for why ... I guess I just see internet explorer (and windows) as
so limiting, that I cannot understand why this is what we are
teaching.
How do children reach high school without knowing what the
internet is, and that it is not the blue "e"?
>I've never worked in any workplace where anything else other than
>Excel was used.
>You can't really separate spreadsheet from Excel, or word processing
>from Word, in the general public's view.
Well. I've never worked anyplace where excel was used for anything
other than a badly designed database. Someone must be teaching
people that is what it is for. ("Formula? What is a formula?")
I also get all kinds of odd documents in my lab. People have no idea
what file formats are and are (understandably) upset when they
cannot print out their papers. And yes, we do have a computer
running windows with office, and we still get strange microsoft
documents that are unopenable.
Papers are generally poorly formatted. Things like using the space
bar or tab key to center things. Then even when the docs do open
up, the formatting is all askew.
Perhaps if teachers thought more about the _abstraction_ of a word
processor and the _abstraction_ of a spreadsheet, and focused on
how these tools are best used -- instead of focusing on how to
use the specific implementations -- we would have fewer problems,
and more capable students.
To me, programming is all about abstraction.
Thanks for your time.
(please follow up to edu-sig)
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Re: [Tutor] Code Readability (was: Recursion and List Comprehensions)
> > I agree. When writing for keeps (i.e. production code) I prefer > > clarity and ease of maintenance over 'elegance' or 'trickiness'. > > This exercise is intended, in part, to sharpen my understanding of > > Python idioms. If I can write highly idiomatic code that works, > > chances are better that I will be able to decipher it when I come > > across it elsewhere. > Since when is elegance a dirty word? It's not. But there are tradeoffs. As a concrete example, we can take a look at Bram Cohen's fairly recent request for a pure-Python suffix tree implmementation: http://www.livejournal.com/users/bramcohen/22069.html He's specifically requesting for an implementation for a data structure algorithm that is easy to maintain, and he's willing to sacrifice the elegant optimal solution! But that's because he wants to make sure he can understand the code later on. I'm not sure I agree with Bram --- the "Ukkonen" algorithm for building suffix trees isn't bad, and I can probably cook it up if I'm careful --- but I can see why he values a simple implementation. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Code Readability (was: Recursion and List Comprehensions)
Sorry. *blush* That was some late Friday night craziness. I just looked at the code being discussed: retList=[word[pos]+item for item in permute3(word[0:pos]+word[pos+1:])] And really didn't want to anybody to confuse that with Python's idea of elegance. List comprehensions can get pretty horrible when combined with nested functions and/or slices and/or multiple implicit loops. One of the few areas where Python can get really twisted. That's a great point, Danny. For me, elegance is an admirable goal under any circumstance, but includes all the aspects I listed. Effeciency -and- understandability. Throw it under the umbrella of "graceful" :) The tools we use are far from perfect, and there are still plenty of "aha!" moments to go around. In the real world the fast and ugly usually go hand in hand. I'm an optimist, tho. Anyway, sorry to go so far off topic. Oh, and by the way, I loved 'The Psychology of Programming'. That was a really entertaining book, and thanks again for recommending it. Andrew On 10/29/05, Danny Yoo <[EMAIL PROTECTED]> wrote: > > > > I agree. When writing for keeps (i.e. production code) I prefer > > > clarity and ease of maintenance over 'elegance' or 'trickiness'. > > > This exercise is intended, in part, to sharpen my understanding of > > > Python idioms. If I can write highly idiomatic code that works, > > > chances are better that I will be able to decipher it when I come > > > across it elsewhere. > > > Since when is elegance a dirty word? > > It's not. But there are tradeoffs. As a concrete example, we can take a > look at Bram Cohen's fairly recent request for a pure-Python suffix tree > implmementation: > > http://www.livejournal.com/users/bramcohen/22069.html > > He's specifically requesting for an implementation for a data structure > algorithm that is easy to maintain, and he's willing to sacrifice the > elegant optimal solution! But that's because he wants to make sure he can > understand > I'm not sure I agree with Bram --- the "Ukkonen" algorithm for building > suffix trees isn't bad, and I can probably cook it up if I'm careful --- > but I can see why he values a simple implementation. > > d the code later on. > ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
