Re: [Tutor] Does IPython have a "restart"?
At 07:55 AM 7/16/2008, Dick Moores wrote: I mean something equivalent to what you get when you do a Ctrl+F6 in IDLE: >>> import math >>> math.log(3) 1.0986122886681098 >>> === RESTART === >>> math.log(3) Traceback (most recent call last): File "", line 1, in math.log(3) NameError: name 'math' is not defined >>> === Got this from the ipython-user list: Use %reset: In [1]: import math In [2]: math.sin(3) Out[2]: 0.14112000805986721 In [3]: %reset Once deleted, variables cannot be recovered. Proceed (y/[n])? y In [5]: math.sin(3) --- NameError Traceback (most recent call last) /home/fperez/Desktop/ in () NameError: name 'math' is not defined Note that it is NOT the same though: idle forces a new, fresh python process, while ipython just clears your current variables. So things like reloading extension modules won't work the same way. Dick ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Unittest
You get the "D" characters when decoding Russian encoded in UTF-8 using Latin-1
instead.
# coding: utf-8
x=u'Зарегистрироваться'
print x.encode('utf-8').decode('latin-1')
ÐаÑегиÑÑÑиÑоваÑÑÑÑ
Check that your html encoding is declared correctly.
--
Mark
"Oleg Oltar" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED]
Ok, seems it's my console setting. Tried console with koi8-r (from
http://vak.ru/doku.php/macosx-russian), and it looks ok there. Mean the
satndard output, but still getting "D" chars instead of russian when trying to
convert it to html via HTMLTestRunner (see
http://tungwaiyip.info/software/HTMLTestRunner.html)
On Thu, Jul 17, 2008 at 9:33 AM, Oleg Oltar <[EMAIL PROTECTED]> wrote:
And in case:
# coding: utf-8
import traceback
try:
raise Exception(u'Зрегиться')
except Exception,e:
print traceback.format_exc().decode('utf-8').encode('cp437',
'replace')
Getting
beryl:~ oleg$ python ./wish/newaccount/reg.py
Traceback (most recent call last):
File "./wish/newaccount/reg.py", line 5, in
raise Exception(u'?')
Exception:
My console settings:
In [1]: import sys
In [2]: sys.getdefaultencoding()
Out[2]: 'ascii'
In [3]: sys.stdout.encoding
Out[3]: 'US-ASCII'
On Thu, Jul 17, 2008 at 9:30 AM, Oleg Oltar <[EMAIL PROTECTED]> wrote:
OK
the output:
# coding: utf-8
import traceback
try:
raise Exception(u'Зрегиться')
except Exception,e:
print traceback.format_exc().decode('utf-8')
>>> Traceback (most recent call last):
File "/var/folders/PC/PCtFE4gQGiqpQymiAScfnk+++TM/-Tmp-/py46506ECT",
line 7, in
print traceback.format_exc().decode('utf-8')
UnicodeEncodeError: 'ascii' codec can't encode characters in position
148-156: ordinal not in range(128)
On Thu, Jul 17, 2008 at 8:13 AM, Mark Tolonen <[EMAIL PROTECTED]> wrote:
The Exception is output in the encoding of the source file. If the
terminal you are displaying the exception on is in a different encoding, it
will be garbled. I'm not familiar with OS X's terminal. Try running python
and printing sys.stdout.encoding.
Alternatively, wrap your code in a try/except handler and translate the
exception yourself.
# coding: utf-8
import traceback
try:
raise Exception(u'Зарегистрироваться')
except Exception,e:
print traceback.format_exc().decode('utf-8')
The last line translates the utf-8 traceback into Unicode. Printing
Unicode will encode the output with the terminal's decoding. If there are
characters it can't display, you'll still get an error, though. You can be
more explicit however:
print
traceback.format_exc().decode('utf-8').encode('cp437','replace')
In this case you'll get ? whenever a character can't be represented in
the selected encoding. cp437, for example, can't display any russian
characters, so for me (on Windows) I just get all ???. When I tried it
with a character string that could be displayed in cp437, it worked fine:
Traceback (most recent call last):
File "", line 1, in
File "t4.py", line 4, in
raise Exception('MàΓ£ΦΘΩδ')
Exception: MàΓ£ΦΘΩδ
Another option is to redirect the output to a file and read the file
with an editor that can display utf-8 (such as Notepad on Windows).
python testfile.py 2>error.txt # this redirects stderr to
a file.
Hope that helps,
Mark
"Oleg Oltar" <[EMAIL PROTECTED]> wrote in message news:[EMAIL
PROTECTED]
The code
# -*- coding: utf-8 -*-
#!/usr/bin/python
"""
This test case check how system works in the situation, when user
tries to use already
used username (domain)
We are creating two accounts with such parameters:
1. Sex = Femle
2. Name1=Name2 = foobar%S
3. Pass1 = Name
4. Pass2 = Name
5. Email address1 = Email address2 = [EMAIL PROTECTED]
In the test we use verification point - warning message about
incorrect input of domain name and the
sugestion message
"""
from selenium import selenium
import unittest, time, re
import HTMLTestRunner
import config
import Creating_account_basic
class Same_domain_name(unittest.TestCase):
def setUp(self):
self.name = "foobar"
self.email = self.name + "@meta.ua"
self.verificationErrors = []
self.selenium = selenium("localhost", ,config.browser,
config.link)
Re: [Tutor] Any way of monitoring a python program's memory utilization?
> > I'm iterating through a vey large tarfile (uncompressed, it would be about > 2.4G, with about 2.5 million files in it) and I can see from some external > monitors that its virtual storage usage just grows and grows, until my > whole system finally grinds to a halt after about 1.2 million members have > been processed. Well, you can check whether your system has reached its limits or not, but what for ? it will lead you no where as the only sthing you can do is stop your program (while MEM_stat <= 1G: parse(); else: break) & you don't get anything done. I believe installing more memroy in your system is the way to go, you need to have at least 3G of Memory (memory is cheap these days), then don't let python use it as you don't know how much memory it will need for your program's internal routines, but create a virtual drive in memory (RAM DRIVE) extract the tar file into it & parse its content as you wish (ofcourse you can use harddrive too ut its gona be VERY slow (specialy on Windows)). ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Any way of monitoring a python program's memory utilization?
On Thu, 17 Jul 2008, Monika Jisswel wrote: > Well, you can check whether your system has reached its limits or not, but > what for ? So I can debug the problem. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] IPython problem: Difficulty in setting editor to TextPad
Win XP, Python 2.51, IPython 0.84
In my ipy_user_conf.py I have put this line:
ipy_editors.install_editor("C:\Program Files\TextPad 5\TextPad.exe")
I use IPython -debug to start IPython, and this is what it tells me:
'editor': '"C:\\Program Files\\TextPad 5\\textpad.exe"',
but
In [3]: ed versions.py
Editing... > C:\Program Files\TextPad 5\TextPad.exe
'C:\Program' is not recognized as an internal or external command,
operable program or batch file.
done. Executing edited code...
[snip]
It seems obvious that there still is a problem with the spaces in the
path, but I don't know what to do about them.
Help, please.
Dick Moores
Have you seen the video introducing the terrific and free
IDE, Ulipad? Download it from my website.
Re: [Tutor] Unittest
beryl:~ oleg$ env
MANPATH=/usr/share/man:/usr/local/share/man:/usr/X11/man
TERM_PROGRAM=Apple_Terminal
TERM=xterm-color
SHELL=/bin/bash
TMPDIR=/var/folders/PC/PCtFE4gQGiqpQymiAScfnk+++TM/-Tmp-/
Apple_PubSub_Socket_Render=/tmp/launch-UNXiC6/Render
TERM_PROGRAM_VERSION=237
USER=oleg
COMMAND_MODE=unix2003
SSH_AUTH_SOCK=/tmp/launch-hfpsIl/Listeners
__CF_USER_TEXT_ENCODING=0x1F6:0:0
PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin
PWD=/Users/oleg
LANG=ru_RU.UTF-8
SHLVL=1
HOME=/Users/oleg
PYTHONPATH=:/Users/oleg/Documents/wishes_Test
LOGNAME=oleg
DISPLAY=/tmp/launch-1kgALC/:0
SECURITYSESSIONID=a206d0
On Thu, Jul 17, 2008 at 9:58 AM, Oleg Oltar <[EMAIL PROTECTED]> wrote:
> See previous message (sent it few seconds ago)
>
>
> On Thu, Jul 17, 2008 at 9:55 AM, Mark Tolonen <[EMAIL PROTECTED]<[EMAIL
> PROTECTED]>>
> wrote:
>
>> OK, your console is set to 'ascii' ('cp437' was my example and is the
>> Windows console encoding). 'ascii' won't be able to display Russian.
>> It shouldn't have displayed the "ИзвениÑ" characters either.
>> Are you still running on the same terminal that display those
>> characters? Can you change your terminals encoding preference via an
>> environment variable?
>> --
>> Mark
>>
>> "Oleg Oltar" <[EMAIL PROTECTED]> wrote in message
>> news:[EMAIL PROTECTED]
>>
>> And in case:
>> # coding: utf-8
>>
>> import traceback
>> try:
>> raise Exception(u'Зрегиться')
>> except Exception,e:
>> print traceback.format_exc().decode('utf-8').encode('cp437',
>> 'replace')
>>
>>
>> Getting
>>
>> beryl:~ oleg$ python ./wish/newaccount/reg.py
>> Traceback (most recent call last):
>> File "./wish/newaccount/reg.py", line 5, in
>> raise Exception(u'?')
>> Exception:
>>
>>
>>
>> My console settings:
>>
>> In [1]: import sys
>>
>> In [2]: sys.getdefaultencoding()
>> Out[2]: 'ascii'
>>
>> In [3]: sys.stdout.encoding
>> Out[3]: 'US-ASCII'
>>
>>
>> On Thu, Jul 17, 2008 at 9:30 AM, Oleg Oltar <[EMAIL PROTECTED]>
>> wrote:
>>
>>> OK
>>> the output:
>>>
>>> # coding: utf-8
import traceback
try:
raise Exception(u'Зрегиться')
except Exception,e:
print traceback.format_exc().decode('utf-8')
>>>
>>>
>>> >>> Traceback (most recent call last):
>>> File "/var/folders/PC/PCtFE4gQGiqpQymiAScfnk+++TM/-Tmp-/py46506ECT",
>>> line 7, in
>>> print traceback.format_exc().decode('utf-8')
>>> UnicodeEncodeError: 'ascii' codec can't encode characters in position
>>> 148-156: ordinal not in range(128)
>>>
>>>
>>>
>>>
>>> On Thu, Jul 17, 2008 at 8:13 AM, Mark Tolonen <[EMAIL PROTECTED]<[EMAIL
>>> PROTECTED]>>
>>> wrote:
>>>
The Exception is output in the encoding of the source file. If the
terminal you are displaying the exception on is in a different encoding, it
will be garbled. I'm not familiar with OS X's terminal. Try running
python
and printing sys.stdout.encoding.
Alternatively, wrap your code in a try/except handler and translate the
exception yourself.
# coding: utf-8
import traceback
try:
raise Exception(u'Зарегистрироваться')
except Exception,e:
print traceback.format_exc().decode('utf-8')
The last line translates the utf-8 traceback into Unicode. Printing
Unicode will encode the output with the terminal's decoding. If there are
characters it can't display, you'll still get an error, though. You can be
more explicit however:
print
traceback.format_exc().decode('utf-8').encode('cp437','replace')
In this case you'll get ? whenever a character can't be represented in
the selected encoding. cp437, for example, can't display any russian
characters, so for me (on Windows) I just get all ???. When I
tried
it with a character string that could be displayed in cp437, it worked
fine:
Traceback (most recent call last):
File "", line 1, in
File "t4.py", line 4, in
raise Exception('MàΓ£ΦΘΩδ')
Exception: MàΓ£ΦΘΩδ
Another option is to redirect the output to a file and read the file
with an editor that can display utf-8 (such as Notepad on Windows).
python testfile.py 2>error.txt # this redirects stderr to a
file.
Hope that helps,
Mark
"Oleg Oltar" <[EMAIL PROTECTED]> wrote in message
news:[EMAIL PROTECTED]
> The code
# -*- coding: utf-8 -*-
#!/usr/bin/python
"""
This test case check how system works in the situation, when user tries
to use already
used username (domain)
We are creating two accounts with such parameters:
1. Sex = Femle
2. Name1=Name2 = foobar%S
3. Pass1 = Name
4. Pass2 = Name
5. Email address1 = Email address2 = [EMAIL PROTECTED]
In the test we use verification point - warning message
Re: [Tutor] Unittest
And also:
Getting this in console when trying to generate report via HTMLTestRunner
(it displayed text correctly when tried simple unittest.main)
pass
output_list['pt1.1'] =
'!!! True\nÐ"омен \'foobar\' занÑÑ. РекомендованнÑе
ÑвободнÑе доменÑ: ffoobar foobar.foobar foofoo
fofo\n[]\n';
On Thu, Jul 17, 2008 at 10:01 AM, Oleg Oltar <[EMAIL PROTECTED]> wrote:
> beryl:~ oleg$ env
> MANPATH=/usr/share/man:/usr/local/share/man:/usr/X11/man
> TERM_PROGRAM=Apple_Terminal
> TERM=xterm-color
> SHELL=/bin/bash
> TMPDIR=/var/folders/PC/PCtFE4gQGiqpQymiAScfnk+++TM/-Tmp-/
> Apple_PubSub_Socket_Render=/tmp/launch-UNXiC6/Render
> TERM_PROGRAM_VERSION=237
> USER=oleg
> COMMAND_MODE=unix2003
> SSH_AUTH_SOCK=/tmp/launch-hfpsIl/Listeners
> __CF_USER_TEXT_ENCODING=0x1F6:0:0
> PATH=/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin:/usr/X11/bin
> PWD=/Users/oleg
> LANG=ru_RU.UTF-8
> SHLVL=1
> HOME=/Users/oleg
> PYTHONPATH=:/Users/oleg/Documents/wishes_Test
> LOGNAME=oleg
> DISPLAY=/tmp/launch-1kgALC/:0
> SECURITYSESSIONID=a206d0
>
>
>
> On Thu, Jul 17, 2008 at 9:58 AM, Oleg Oltar <[EMAIL PROTECTED]> wrote:
>
>> See previous message (sent it few seconds ago)
>>
>>
>> On Thu, Jul 17, 2008 at 9:55 AM, Mark Tolonen <[EMAIL PROTECTED]<[EMAIL
>> PROTECTED]>>
>> wrote:
>>
>>> OK, your console is set to 'ascii' ('cp437' was my example and is the
>>> Windows console encoding). 'ascii' won't be able to display Russian.
>>> It shouldn't have displayed the "ИзвениÑ" characters either.
>>> Are you still running on the same terminal that display those
>>> characters? Can you change your terminals encoding preference via an
>>> environment variable?
>>> --
>>> Mark
>>>
>>> "Oleg Oltar" <[EMAIL PROTECTED]> wrote in message
>>> news:[EMAIL PROTECTED]
>>>
>>> And in case:
>>> # coding: utf-8
>>>
>>> import traceback
>>> try:
>>> raise Exception(u'Зрегиться')
>>> except Exception,e:
>>> print traceback.format_exc().decode('utf-8').encode('cp437',
>>> 'replace')
>>>
>>>
>>> Getting
>>>
>>> beryl:~ oleg$ python ./wish/newaccount/reg.py
>>> Traceback (most recent call last):
>>> File "./wish/newaccount/reg.py", line 5, in
>>> raise Exception(u'?')
>>> Exception:
>>>
>>>
>>>
>>> My console settings:
>>>
>>> In [1]: import sys
>>>
>>> In [2]: sys.getdefaultencoding()
>>> Out[2]: 'ascii'
>>>
>>> In [3]: sys.stdout.encoding
>>> Out[3]: 'US-ASCII'
>>>
>>>
>>> On Thu, Jul 17, 2008 at 9:30 AM, Oleg Oltar <[EMAIL PROTECTED]>
>>> wrote:
>>>
OK
the output:
# coding: utf-8
>
> import traceback
> try:
> raise Exception(u'Зрегиться')
> except Exception,e:
> print traceback.format_exc().decode('utf-8')
>
>>> Traceback (most recent call last):
File "/var/folders/PC/PCtFE4gQGiqpQymiAScfnk+++TM/-Tmp-/py46506ECT",
line 7, in
print traceback.format_exc().decode('utf-8')
UnicodeEncodeError: 'ascii' codec can't encode characters in position
148-156: ordinal not in range(128)
On Thu, Jul 17, 2008 at 8:13 AM, Mark Tolonen <[EMAIL PROTECTED]<[EMAIL
PROTECTED]>>
wrote:
> The Exception is output in the encoding of the source file. If the
> terminal you are displaying the exception on is in a different encoding,
> it
> will be garbled. I'm not familiar with OS X's terminal. Try running
> python
> and printing sys.stdout.encoding.
>
> Alternatively, wrap your code in a try/except handler and translate the
> exception yourself.
>
> # coding: utf-8
> import traceback
> try:
> raise Exception(u'Зарегистрироваться')
> except Exception,e:
> print traceback.format_exc().decode('utf-8')
>
> The last line translates the utf-8 traceback into Unicode. Printing
> Unicode will encode the output with the terminal's decoding. If there are
> characters it can't display, you'll still get an error, though. You can
> be
> more explicit however:
>
> print
> traceback.format_exc().decode('utf-8').encode('cp437','replace')
>
> In this case you'll get ? whenever a character can't be represented in
> the selected encoding. cp437, for example, can't display any russian
> characters, so for me (on Windows) I just get all ???. When I
> tried
> it with a character string that could be displayed in cp437, it worked
> fine:
>
> Traceback (most recent call last):
> File "", line 1, in
> File "t4.py", line 4, in
> raise Exception('MàΓ£ΦΘΩδ')
> Exception: MàΓ£ΦΘΩδ
>
> Another option is to redirect the output to a file and read the file
> with an editor that can display utf-8 (such as Notepad on Windows).
>
> python testfile.py 2>error.txt # this redirects stderr to
> a file.
>
> Hope that helps,
> Mark
>
>
Re: [Tutor] Any way of monitoring a python program's memory utilization?
I see no problem, if you open very BIG files then your memory will get filled up & your system will halt, can you buy more food than your fridge can handle , and write to a list asking to invistigate the problem ? 2008/7/17 Terry Carroll <[EMAIL PROTECTED]>: > On Thu, 17 Jul 2008, Monika Jisswel wrote: > > > Well, you can check whether your system has reached its limits or not, > but > > what for ? > > So I can debug the problem. > > ___ > 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] How to populate a dictionary
Hello, I am taking python this summer, and have run into a problem.
The assignment is to create a dictionary from a text file:
"12/07/0526 = St Felix IV begins his reign as Catholic Pope"
"12/07/1109 = Crusaders capture Syria's harbor city of Tripoli"
"12/07/1191 = Richard Coeur de Lion and Crusaders defeat Saracens in Palestine"
"12/07/1290 = Jews are expelled from England by order of King Edward I"
"12/07/1442 = King Alfonso V of Arag¢n becomes king of Naples"
"Create a dictionary of dates. Each date you have in there should have a
special event. An example would be that the dictionary would contain the
following
NOTE: You must have at least 100 different dates. You can get this from lists
on the internet if you like, but it must be something real, not just garbage or
something just made up.
12/28/1929: My Birthday
1/1/1948: New Years Day 48
9/11: the big one
Your program should start by creating an empty dictionary called dates. Then
your program will get an array of ALL the keys for that dictionary and then
write a loop that will display all the key/value pairs.
BUT: The dictionary setup file should exist OUTSIDE of the program, you should
have lines in it that say something like "12/28/1948=Starting Day" or something
like that. Your strategy will be to open that file, read it, split it into
lines, then for each line, you will split that line by the equals = sign. The
left side value is the Key and the Right Hand Side is the value.
You will read this whole files, splitting each key/value pair and store them in
a dictionary. Then write the loop which will get all the keys, SORT those keys
and print out the key/value pairs.
here is a sample of my code:
#!python
myDictionary = { }
inputLines = open ("dates.txt") .read() .split ("\n")
for i in range ( len(inputLines) ) :
if (inputLines [i] != "") :
leftHandSide = inputLines [i].split ("=")
rightHandSide = inputLines [i].split ("=")
myDictionary [leftHandSide] = rightHandSide
theKeys = myDictionary.keys ()
theKeys.sort ()
for i in range (len (theKeys) ):
print theKeys[i], myDictionary[ theKeys[i] ]
Can anyone help?
___
Tutor maillist - Tutor@python.org
http://mail.python.org/mailman/listinfo/tutor
[Tutor] Recursive function
hi all,
i am new to programming, i just started writing scripts in python about
functions.There is a program by name hangman where in i take input three
characters and then concatenate the resultant output is compared to a three
letter string, if it is similar it will display the word as correct if not i
want to execute the same function which evokes to prompt for three
characters as input. The problem is i am not getting a runtime error.
below is the piece of code:
#word Hangman
print "Welcome to the Hangman"
print
print
a = raw_input("enter 1st letter=")
b = raw_input("enter 2nd letter=")
c = raw_input("enter 3rd letter=")
def cmp():
d = (a+b+c);
if (d=='PAN'):
print "word" 'd' "is correct"
else:
print "Try Again"
CALL();
def CALL():
cmp();
cmp()
--
Raghavendra Vanam
___
Tutor maillist - Tutor@python.org
http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] How to populate a dictionary
josetjr wrote...
>Hello, I am taking python this summer, and have run into a problem.
Let me suggest some improvements. You can process all the lines in a
textfile like this:
for line in open("dates.txt").readlines():
print line
Furthermore, if you have a string in the form of "ABC=DEF", you can split it
like this:
key,value=s.split("=")
To enumerate the keys of a dictionary in alphabetical order, you can use:
for k in sorted(d):
print k
So, your little homework program becomes more pythonic like this:
history={}
for line in open("dates.txt").readlines():
line=line.strip("\n\"") # clean the line a bit; strip off the newline
and quotes
date,event=line.split("=")
history[date]=event
for k in sorted(history):
print k,history[k]
Have a nice day,
--
"The ability of the OSS process to collect and harness
the collective IQ of thousands of individuals across
the Internet is simply amazing." - Vinod Vallopillil
http://www.catb.org/~esr/halloween/halloween4.html
___
Tutor maillist - Tutor@python.org
http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] How to populate a dictionary
Dates = {}
def read_Dates (Dates):
if os.path.exists(FILE_NAME):
store = open(FILE_NAME,'r')
for line in store:
name = line.rstrip()
entry = store.next().rstrip()
Dates[name] = entry
store.close()
def save_Dates (Dates):
store = open(FILE_NAME, 'w')
for name,entry in Dates.items():
store.write(name + '\n')
store.write(entry + '\n')
store.close()
print "%s File Saved and Closed!" % FILE_NAME
- Original Message -
From: [EMAIL PROTECTED]
To: tutor@python.org
Sent: Thursday, July 17, 2008 8:07 AM
Subject: [Tutor] How to populate a dictionary
Hello, I am taking python this summer, and have run into a problem.
The assignment is to create a dictionary from a text file:
"12/07/0526 = St Felix IV begins his reign as Catholic Pope"
"12/07/1109 = Crusaders capture Syria's harbor city of Tripoli"
"12/07/1191 = Richard Coeur de Lion and Crusaders defeat Saracens in Palestine"
"12/07/1290 = Jews are expelled from England by order of King Edward I"
"12/07/1442 = King Alfonso V of Arag¢n becomes king of Naples"
"Create a dictionary of dates. Each date you have in there should have a
special event. An example would be that the dictionary would contain the
following
NOTE: You must have at least 100 different dates. You can get this from lists
on the internet if you like, but it must be something real, not just garbage or
something just made up.
12/28/1929: My Birthday
1/1/1948: New Years Day 48
9/11: the big one
Your program should start by creating an empty dictionary called dates. Then
your program will get an array of ALL the keys for that dictionary and then
write a loop that will display all the key/value pairs.
BUT: The dictionary setup file should exist OUTSIDE of the program, you should
have lines in it that say something like "12/28/1948=Starting Day" or something
like that. Your strategy will be to open that file, read it, split it into
lines, then for each line, you will split that line by the equals = sign. The
left side value is the Key and the Right Hand Side is the value.
You will read this whole files, splitting each key/value pair and store them in
a dictionary. Then write the loop which will get all the keys, SORT those keys
and print out the key/value pairs.
here is a sample of my code:
#!python
myDictionary = { }
inputLines = open ("dates.txt") .read() .split ("\n")
for i in range ( len(inputLines) ) :
if (inputLines [i] != "") :
leftHandSide = inputLines [i].split ("=")
rightHandSide = inputLines [i].split ("=")
myDictionary [leftHandSide] = rightHandSide
theKeys = myDictionary.keys ()
theKeys.sort ()
for i in range (len (theKeys) ):
print theKeys[i], myDictionary[ theKeys[i] ]
Can anyone help?
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Re: [Tutor] How to populate a dictionary
Several reactions: --- As I understood it the list policy is: 1) not solve homework problems. 2) request students to tell us exactly what problems they were running into e.g. expected output, actual output, exceptions, ... 3) then give specific suggestions We seem to have violated that policy in this case. Can we in agreement on the policy? --- I also prefer list posts to be in plain text rather than various fonts, sizes and colors. --- I think that assignment is very poorly worded! Why the busywork of coming up with 100 real dates. What does that have to do with programming? -- Bob Gailer 919-636-4239 Chapel Hill, NC ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Any way of monitoring a python program's memoryutilization?
"Monika Jisswel" <[EMAIL PROTECTED]> wrote... I see no problem, if you open very BIG files then your memory will get filled up & your system will halt, Only if you were to foolishly read the whole file into memory at once. Early computers only had memories of a few kilobytes but could process files much larger than that - I recall using one with only 16K RAM and no hard drive( a server not a home computer) that was able to process data files of several megabytes. And many PC databases are 10's of GB in size and a database is no more than a few very big files. Given that many PCs have a hardware upper memory limit of 2G and 32bit processors a limit of 4G that would make life very difficult if we were restricted in file size by the RAM available. You just have to make sure you read the files in small chunks. and process each chunk in turn. (A technique usually referred to as paging.) In python the chunk size is usually a line... There is only a problem if you try saving all of the lines into a collection of some sort So I can debug the problem. The problem he is trying to debug is why the files are using up his memory when he (presumably) was not expecting them to fill it. To use the fridge analogy, why is the fridge still full after I've eaten all the food? Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] How to populate a dictionary
<[EMAIL PROTECTED]> wrote
The assignment is to create a dictionary from a text file:
ok, since it's 'homework' I won't give the whole answer but will try
to point you in the right direction.
Your program should start by creating an empty dictionary called
dates.
Then your program will get an array of ALL the keys for that
dictionary
and then write a loop that will display all the key/value pairs.
OK, I'm not sure why they want you to build an array, its not really
necessary...
you should have lines in it that say something like
"12/28/1948=Starting Day"
open that file, read it, split it into lines, then for each line,
Again you don;t need to do all of that, Python has a function
readlines() that does it all for you.
you will split that line by the equals = sign.
The left side value is the Key and the Right Hand Side is the value.
You will read this whole files, splitting each key/value pair and
store them in a dictionary.
You can do this one line at a time rather than reading the file
then going back over it to split/store the data.
Then write the loop which will get all the keys,
SORT those keys and print out the key/value pairs.
OK, Again thats a bit off track as a sequence. I'd get the keys,
sort them then write a loop over the sorted keys to display the
results.
myDictionary = { }
#AG-You were asked to call it dates!
inputLines = open ("dates.txt") .read() .split ("\n")
for i in range ( len(inputLines) ) :
Could just be:
for line in open("dates.txt"):
if (inputLines [i] != "") :
leftHandSide = inputLines [i].split ("=")
rightHandSide = inputLines [i].split ("=")
These two lines do the same split. You need to store the first split
value in one variable and the second in the other. (Remember split()
returns a list). Try:
lhs, rhs = line.split('=')
myDictionary [leftHandSide] = rightHandSide
theKeys = myDictionary.keys ()
theKeys.sort ()
for i in range (len (theKeys) ):
print theKeys[i], myDictionary[ theKeys[i] ]
Rather than indexing via range(len()), a Python for loop is best used
to get the items directly. Thus:
for key in theKeys:
print key, dates[key]
See how much more readable it is? And how much less typing!
If you have a recent version of Python you can also avoid the
business of extracting the keys and sorting them by using the
sorted() function on the dates directly as part of the for loop.
I'll leave that as an extra research topic! :-)
HTH,
--
Alan Gauld
Author of the Learn to Program web site
http://www.freenetpages.co.uk/hp/alan.gauld
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Re: [Tutor] How to populate a dictionary
"Michiel Overtoom" <[EMAIL PROTECTED]> wrote
Let me suggest some improvements. You can process all the lines in a
textfile like this:
for line in open("dates.txt").readlines():
print line
Or just
for line in open("dates.txt"):
print line.rstrip()
So, your little homework program becomes more pythonic like this:
Spoilsport, you showed him the answer! :-)
Alan G
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Re: [Tutor] How to populate a dictionary
"bob gailer" <[EMAIL PROTECTED]> wrote As I understood it the list policy is: 1) not solve homework problems. 2) request students to tell us exactly what problems they were running into e.g. expected output, actual output, exceptions, ... 3) then give specific suggestions We seem to have violated that policy in this case. Can we in agreement on the policy? So far as I know the policy remains as it always was Bob. I also prefer list posts to be in plain text rather than various fonts, sizes and colors. I haven't had that problem. They are all in plain text whenI get them, but thats probably my mail/news reader settings I think that assignment is very poorly worded! I agree, the recommended sequence to solve is not great, but it's better than some homework assignments I've seen posted here. Why the busywork of coming up with 100 real dates. What does that have to do with programming? Agreed, thats just silly. Unless the course is also trying to teach research skills! Alan G. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] IPython problem: Difficulty in setting editor to TextPad
"Dick Moores" <[EMAIL PROTECTED]> wrote
In my ipy_user_conf.py I have put this line:
ipy_editors.install_editor("C:\Program Files\TextPad 5\TextPad.exe")
escape the spaces and backslashes(raw string might work as well)
ipy_editors.install_editor("C:\\Program\ Files\\TextPad
5\\TextPad.exe")
OR maybe
ipy_editors.install_editor(r"C:\Program Files\TextPad 5\TextPad.exe")
Alan G
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Re: [Tutor] IPython problem: Difficulty in setting editor to TextPad
At 08:13 AM 7/17/2008, Alan Gauld wrote:
"Dick Moores" <[EMAIL PROTECTED]> wrote
In my ipy_user_conf.py I have put this line:
ipy_editors.install_editor("C:\Program Files\TextPad 5\TextPad.exe")
escape the spaces and backslashes(raw string might work as well)
Yeah, I tried that (except for the raw string).
ipy_editors.install_editor("C:\\Program\ Files\\TextPad 5\\TextPad.exe")
OR maybe
ipy_editors.install_editor(r"C:\Program Files\TextPad 5\TextPad.exe")
I finally got some help from one of the main IPython guys (just now).
The line that partially works is
ipy_editors.install_editor('"C:\Program Files\TextPad 5\TextPad.exe"
${file}(${line})')
But using the line number doesn't work, so I skip it and do
In [3]: ed versions.py
Editing... > "C:\Program Files\TextPad 5\TextPad.exe" versions.py(0)
This DOES open versions.py in Textpad, with the caret at line 1.
Thanks for your educated guesses, Alan.
Dick
==
Have you seen the video introducing the terrific
and free IDE, Ulipad? Download it from my website.
Re: [Tutor] Recursive function
"vanam" <[EMAIL PROTECTED]> wrote
i am new to programming, i just started writing scripts in python
about
functions.
You need to check the section of your tutorial/book that
discusses loops. That will make your solution much easier.
characters as input. The problem is i am not getting a runtime
error.
Tell us what you are getting (and what you expected), it makes our
job easier if we don't have to guess.
below is the piece of code:
#word Hangman
print "Welcome to the Hangman"
print
print
a = raw_input("enter 1st letter=")
b = raw_input("enter 2nd letter=")
c = raw_input("enter 3rd letter=")
def cmp():
You shouldn't write functions with the same name as builtin
functions. You will not be able to use the builtin one if you do!
cmp() is the builtin Python function for comparing two things.
d = (a+b+c);
You could just have read the three letters at once using
raw_input...
if (d=='PAN'):
print "word" 'd' "is correct"
else:
print "Try Again"
CALL();
def CALL():
cmp();
You don;t need CALL, you could just have called cmp from
inside cmp - this is known as a recursice call and is allowed
in Python. It can be used to create a loop effect here as you
do but it has a limited number of repetitions and is best not
used for that purpose. Instead use the built in looping
constructs in Python "for" or "while"
In your case you probabnly want something like:
d = ""
while d != "PAN":
# code inserted here
print "Word", d, "is correct" # only prints when d == PAN
HTH,
--
Alan Gauld
Author of the Learn to Program web site
http://www.freenetpages.co.uk/hp/alan.gauld
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[Tutor] continuouse loop
Would a program using a continuouse loop such as in this code take up resources on the system if left for long period ? import sys > > while 1: > self.data = sys.stdin.readline() > self.function_1(data) > What are my other options is I want to have a running program & other programs communicate with it & get responses from it ? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] continuouse loop
"Monika Jisswel" <[EMAIL PROTECTED]> wrote Would a program using a continuouse loop such as in this code take up resources on the system if left for long period ? Any running program takes up some resources but whether this one would increase its resource usage over time, which I assume is what you want to know, would depend on what it did with self.data and what happened in self.function_1. If function_1 did nothing that was resource intensive - like build a big list in memory or open a new file each time it was called (and not release it) - then it would be fine. But if function_1 stored data in a list or opened a new comms port on each call then yes it will eat up resources. import sys while 1: self.data = sys.stdin.readline() self.function_1(data) What are my other options is I want to have a running program & other programs communicate with it & get responses from it ? The trick to writing long running processes such as Windows services and Unix daemons is to ensure they are either stateless (the create use and free the needed resources in each operation) or utilise pools (pre-allocated sets of resources that are allocated to a function as needed and released by the function when done - if you run out of pool you take a decision to enlarge the pool or to stop servicing requests until resource becomes available - possibly using a queue if instant response is not critical) Thee are framweworks around, such as twisted, that help with these tasks. HTH, -- Alan Gauld Author of the Learn to Program web site http://www.freenetpages.co.uk/hp/alan.gauld ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Any way of monitoring a python program's memory utilization?
On Thu, 17 Jul 2008, Monika Jisswel wrote: > I see no problem, if you open very BIG files then your memory will get > filled up & your system will halt, I'm going to disagree with you on this one. First, in general, it is not the case that opening a very large file will cause memory to be filled up. In general, only the portion of the file that is being processed needs to actually be in memory. A tarfile appears to be an exception to that general rule. The question is, why? Can that exception be avoided and a program that's processing a tar file be as well-behaved in terms of resource consumption as a program that processes other types of files? Second, although most resource constraint problems can often be addressed by buying more resource, that's not usually a good approach. Where, as here, the resource constraint surfaces only in rare cases (i.e., processing a tarfile), the better approach is to find out if something is out of whack with respect to that one case. Simply adding resources is a poor use of, um, resources, for a couple reasons. I'd rather spend my money on a nice dinner than on adding memory to a computer system that is perfectly adequate in every other way, other than in processing a single file. And adding resources, whether memory, disk, or CPU, is a band-aid: it gets you over this hump, but not the next. If I add enough memory to process a 4-Gb file, great, I can now process a 4-Gb file. But if I get a 6-Gb file in a couple months, I have to pull out the checkbook again. But managing the resource utilization is a scalable scheme. > can you buy more food than your fridge can handle , and write to a list > asking to invistigate the problem ? This is such an off-the wall analogy that it's difficult to respond to, but what the heck. First, I'm not writing to the list to ask it to investigate the problem. I'm writing to the list to find out what tools are available so that *I* can investigate the problem. Second, under this analogy, you're looking at a scenario where food is put into a refrigerator in containers, and when consumed, the containers are left in the refrigerator. Now, your solution here might be to keep buying more or larger refrigerators. Mine would be to see if I can get rid of all the empty containers that are uselessly occupying space in the refrigerator, so I can utilize the space for useful purposes (refrigerating food) rather than chilling empty containers for no reason. Back to the real Python case: now that I can monitor my memory usage, I can try various strategies to solve the problem, and I can do it with a subset of data. Instead of running the program on a 4Gb file and waiting to see if it blows up or halts my system in 15 minutes after processing a couple gig, I can run it with a much smaller 60 Mb file, and track its effects. For anyone who cares about the real issue: it seems that tarfile.py caches every member it processes in an internal list. The list isn't actually used if accessing the file as an iterator, so by reinitializing it to [], the memory consumption problem is avoided. This breaks other methods of the module, which are used to extract particular desired members, but in my case, that's okay. I'm currently experimenting to see if I can come up with a patch that will either allow both means of accessing the members (as an iterator and directly), or, as a less desirable alternative, if a parameter like cache=False is specified, allow access as an iterator and raise an exception if the other methods are used. Thanks to a couple tarfile.py experts on comp.lang.python for their insight on this. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Any way of monitoring a python program's memory utilization?
I m really sorry if no one of you liked/agreed with the fridge analogy but that's what my brain could come up with at the time, I have to say it's not a very scientific argument. but I only meant to say that if you are piping data into memory & this data is larger than that memory then there is no problem with the code but with the data, & I think this paragraph actually confirms some of it : For anyone who cares about the real issue: it seems that tarfile.py caches > every member it processes in an internal list. The list isn't actually > used if accessing the file as an iterator, so by reinitializing it to [], > the memory consumption problem is avoided. This breaks other methods of > the module, which are used to extract particular desired members, but in > my case, that's okay. > but I have to admit I was completely wrong and a new patch to the tarfile module will soon see the light to fix this problem for the rest of ur lives painlessly. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Question on how to do something.
Hello. I'm new to Python and I was wondering how to read all the files in a folder. I used this program or command for single files. import pprint pprint.pprint(open(r'c:\text\somefile.txt').readlines()) And if possible, is there a way to make it so that it waits at the end of each file for a confirmation to go onto the next file? Thanks ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] continuouse loop
Monika Jisswel wrote: > Would a program using a continuouse loop such as in this code take up > resources on the system if left for long period ? > > import sys > > while 1: > self.data = sys.stdin.readline() > self.function_1(data) Not much, I would think, until something is written to stdin of this program, and then it would depend on what function_1 does. > What are my other options is I want to have a running program & other > programs communicate with it & get responses from it ? If I understand what you're asking, there are a few options outlined in the python library reference, here: http://docs.python.org/lib/ipc.html I would add named pipes as another option for *nix, windows may have something similar. And, depending on what you're trying to accomplish maybe xmlrpclib, soappy, pyro, or perhaps even cgi. HTH, Marty ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] creating pop method for stack class
I am almost done with a stack class that I wrote:
#!/usr/bin/python
class Stack(list):
def isempty(self):
length = len(self)
if length == 0:
return True
else:
return False
def peek(self):
length = len(self)
if length == 0:
return 0
else:
last_index = length - 1
return self[last_index]
def stackpop(self):
length = len(self)
if length == 0:
print "Empty list!"
else:
last_index = length - 1
stackpop_val = self[last_index]
self = self[:last_index]
return stackpop_val
def push(self, value):
return self.append(value)
if __name__ == '__main__':
x = True
stack = Stack()
print "Pick an option to modify stack: "
while x == True:
print "1) Peek at the last value"
print "2) Pop off the last value"
print "3) Push a value on the stack"
print "4) Print stack"
print "5) Quit Program"
choice_string = raw_input("Make a choice: ")
try:
choice = int(choice_string)
except ValueError:
sys.exit("Not an integer! Goodbye!")
if choice == 1:
if stack.isempty():
print "Stack is empty"
else:
peek_val = stack.peek()
print peek_val
elif choice == 2:
pop_val = stack.stackpop()
print pop_val
elif choice == 3:
push_val = raw_input("Push this value on stack: ")
stack.push(push_val)
elif choice == 4:
print stack
elif choice == 5:
print "Goodbye!"
x = False
else:
x = False
sys.exit("Wrong response Goodbye!")
My main problem seems to be getting this part to work:
def stackpop(self):
length = len(self)
if length == 0:
print "Empty list!"
else:
last_index = length - 1
stackpop_val = self[last_index]
self = self[:last_index]
return stackpop_val
The easiest solution would be to use the pop method from list, but I decided I
wanted to take a crack at writing my own pop method. Unfortunately, this
always happens when I run the program:
1) Peek at the last value
2) Pop off the last value
3) Push a value on the stack
4) Print stack
5) Quit Program
Make a choice: 3
Push this value on stack: 1
1) Peek at the last value
2) Pop off the last value
3) Push a value on the stack
4) Print stack
5) Quit Program
Make a choice: 3
Push this value on stack: blah
1) Peek at the last value
2) Pop off the last value
3) Push a value on the stack
4) Print stack
5) Quit Program
Make a choice: 3
Push this value on stack: blah blah
1) Peek at the last value
2) Pop off the last value
3) Push a value on the stack
4) Print stack
5) Quit Program
Make a choice: 2
blah blah
1) Peek at the last value
2) Pop off the last value
3) Push a value on the stack
4) Print stack
5) Quit Program
Make a choice: 4
['1', 'blah', 'blah blah']
How come the stack doesn't shrink when I pop off the last value? I tested the
code in the interpreter:
>>> lista = [1,2,3,4]
>>> lista[:len(lista)-1]
[1, 2, 3]
>>> lista = lista[:len(lista)-1]
>>> lista
[1, 2, 3]
Any hints?
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Re: [Tutor] creating pop method for stack class
On 18/07/2008, Christopher Spears <[EMAIL PROTECTED]> wrote: > How come the stack doesn't shrink when I pop off the last value? I tested > the code in the interpreter: > > >>> lista = [1,2,3,4] > >>> lista[:len(lista)-1] > [1, 2, 3] > >>> lista = lista[:len(lista)-1] > >>> lista > [1, 2, 3] First, a tip: Instead of lista[:len(lista)-1], you can (and should) just write lista[:-1]. Now, what if we wrap that in a function: >>> def shorten(lst): ... lst = lst[:-1] # identical to: lst = lst[:len(lst)-1] ... Then test it: >>> lista = [1, 2, 3, 4] >>> shorten(lista) What do you think will be the result of: >>> print lista ? PS. You wrote: > def stackpop(self): > length = len(self) > if length == 0: > print "Empty list!" If you're trying to pop from an empty stack, this is an error condition. Rather than printing a message, the correct way to handle errors in python is by raising exceptions. e.g. def stackpop(self): if len(self) == 0: raise IndexError# or you could define your own exception... > def peek(self): > length = len(self) > if length == 0: > return 0 The same applies here -- peeking at an empty stack should be an error too. Otherwise, how can you tell the difference between an empty stack and a stack where the top item happens to be a 0? -- John. ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] parsing sendmail logs
2008/7/15 Martin Walsh <[EMAIL PROTECTED]>:
> > Any pragmatic advice on building or working with a framework to get
> > to the point where i can do analysis on my logs would be cool.
> >
>
>
> As an exercise, I think it would be a reasonable approach to write
> python derivatives of the shell commands being used, perhaps tailored to
> the data set, to get a feel for working with text data in python. Then
> ask questions here if you get stuck, or need optimization advice. I
> think you'll find you can accomplish this with just a few lines of
> python code for each (sort -u, grep, awk '{print $n}', etc), given your
> use of the commands in the examples provided. Write each as a function,
> and you'll end up with code you can reuse for other log analysis
> projects. Bonus!
>
> HTH,
> Marty
>
>
Hi Marty,
Thanks for the input. I like the idea of writing tailored versions of the
standard unix tools. I think what has held me back from writing more than a
few scripts based on someone elses code is a lack of clarity about what i'm
wanting to write.
I've done a bit of web programming in ASP,PHP and Perl mostly in the
presentation layer, but the shift in domain to sysadmin tasks has for some
reason has been difficult.
To essentially re-write "sort -u" in python has the advantage for me that i
use sort _alot_ so i'm familiar with the concept and it's a small enough
tasks to feel doable. :-)
Your suggestion also provides an insight into how to program that i find
easy to forget. which is to break things down into smaller pieces.
Cheers,
nibuh.
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Re: [Tutor] parsing sendmail logs
2008/7/16 Jeff Younker <[EMAIL PROTECTED]>: > Parsers as referenced in your link are intended for heavy-duty lifting > such as parsing programming languages. > > Sendmail logs are very simple, so those parsers are vast overkill. Split > on whitespace combined with regular expressions should be up to the job. > > -jeff > > Jeff, Thanks for the clarification, I was looking at these parsers thinking they were overkill. split and regex for version 0.0.0.1 of my script looks like the order of the day :-) Cheers, ram, ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
[Tutor] Guidance on jump-starting to learn Python
I have the challenge / opportunity to learn Python quickly. I am technically-minded, but I am not a programmer. When I have tried / used Python before (I've written 5-6 python programs/utilities), it has been solving a particular issue but not learning the proper structure/procedures to learn Python (nor any other programming language). I humbly admit I have cut corners, so I have bad habits. I have been advised to start with the basics but at an accelerated pace. Any recommended "homework" assignments? I have two books as well: Core Python Programming from Wesley Chun , Second Edition. Python Programming for the Absolute Beginner, Second Edition. Thanks so much for your advice/help in advance. Steve ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] creating pop method for stack class
> > First, a tip: > > Instead of lista[:len(lista)-1], you can (and should) just > write lista[:-1]. > > Now, what if we wrap that in a function: > > >>> def shorten(lst): > ... lst = lst[:-1] # identical to: lst = > lst[:len(lst)-1] > ... > > Then test it: > > >>> lista = [1, 2, 3, 4] > >>> shorten(lista) > > What do you think will be the result of: > > >>> print lista > > ? > I see what you mean. I have tested it, and I have gotten a weird result: >>> def shorten(lst): ... lst = lst[:-1] ... >>> lista = [1,2,3,4] >>> shorten(lista) >>> print lista [1, 2, 3, 4] >>> lista = [1,2,3,4] >>> lista = lista[:-1] >>> print lista [1, 2, 3] >>> Strange...why does it work outside of the function but not in it? Let me try something else: >>> def shorten(lst): ... lst = lst[:-1] ... return lst ... >>> lista = [1,2,3,4] >>> shorten(lista) [1, 2, 3] >>> print lista [1, 2, 3, 4] >>> lista = shorten(lista) >>> print lista [1, 2, 3] >>> Huh, how do you explain that? ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Question on how to do something.
"Mitchell Nguyen" <[EMAIL PROTECTED]> wrote in message news:[EMAIL PROTECTED] Hello. I'm new to Python and I was wondering how to read all the files in a folder. Take a look at the fileinput module, I think it will do what you want. Alan G ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] creating pop method for stack class
"Christopher Spears" <[EMAIL PROTECTED]> wrote I am almost done with a stack class that I wrote: Some comments... class Stack(list): def isempty(self): length = len(self) if length == 0: return True else: return False This can just be return bool(len(self)) def peek(self): length = len(self) if length == 0: return 0 How do you know whether zero was the last item or an error? Better to raise an IndexError or a ValueError or define your own StackEmptyError. else: last_index = length - 1 return self[last_index] You don't need the last_index thing, just use -1 -1 is always the last item. def stackpop(self): length = len(self) if length == 0: print "Empty list!" And this is inconsistent with the previous method. Keep your error jhandling style the same or confuse your users. In general putting print statements inside class methods is a bad idea. Raise an exception instead. else: last_index = length - 1 stackpop_val = self[last_index] self = self[:last_index] return stackpop_val I don't think reassigning self is a good idea. I'd go with deleting the last member using del(self[-1]) My main problem seems to be getting this part to work: def stackpop(self): ... self = self[:last_index] return stackpop_val see comment above. HTH, -- Alan Gauld Author of the Learn to Program web site http://www.freenetpages.co.uk/hp/alan.gauld ___ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
