Marc Huffnagle wrote:
Steve Holden wrote:
>>> a,b,c = 1.1, 2.2, 3.3
>>> a,b,c = map(int, (a,b,c))
>>> a,b,c
(1, 2, 3)
>>> a,b,c = [int(x) for x in (a,b,c)]
>>> a,b,c
(1, 2, 3)
regards
Steve
Thanks ... so there's no way to pass an actual variable into a list
mapping, instead of its value? I
Lee Harr wrote:
On 2005-02-03, BJörn Lindqvist <[EMAIL PROTECTED]> wrote:
The process seem slow. I've submitted two patches and haven't gotten
any response so far, but it has only been three weeks. Other patches
seem to be idling for months. I'm not complaining, just want to know
why the process is
Alexander Zatvornitskiy wrote:
Hello All!
I'am trying to make something like this:
CPT={ ['b0','c0']:1, ['b0','c1']:0, ['b1','c0']:3, ['b1','c1']:1 }
but python says "TypeError: list objects are unhashable"
I can replace list with touple: CPT={ ('b0','c0'):1, ('b0','c1'):0, ...and so
on. But, where
Daniel Bickett wrote:
|def setreplace( self , set ):
|"""
|Do multiple replaces at once, using dictionary `set' as a legend,
|where each instance of each key is to be replaced with that key's
|value.
|"""
|if type( set ) == dict:
|resu
fortepianissimo wrote:
Thank you so much about this useful tip! I learned the new decorator
feature of 2.4 simply because of your post.
Unfortunately I don't have luxury right now to run Python 2.4 (for what
I'm doing anyways). You mentioned the way to do decorator in 2.3. Still
I have a question h
I have lists containing values that are all either True, False or None,
e.g.:
[True, None, None, False]
[None, False, False, None ]
[False, True, True, True ]
etc.
For a given list:
* If all values are None, the function should return None.
* If at least one value is True, t
Alan McIntyre wrote:
Hi all,
I have a list of items that has contiguous repetitions of values, but
the number and location of the repetitions is not important, so I just
need to strip them out. For example, if my original list is
[0,0,1,1,1,2,2,3,3,3,2,2,2,4,4,4,5], I want to end up with [0,1,2
Alan McIntyre wrote:
Hi all,
I have a list of items that has contiguous repetitions of values, but
the number and location of the repetitions is not important, so I just
need to strip them out. For example, if my original list is
[0,0,1,1,1,2,2,3,3,3,2,2,2,4,4,4,5], I want to end up with [0,1,2
Raymond Hettinger wrote:
"Steven Bethard"
For a given list:
* If all values are None, the function should return None.
* If at least one value is True, the function should return True.
* Otherwise, the function should return False.
. . .
Right now, my code looks like:
if T
Mike C. Fletcher wrote:
Alan McIntyre wrote:
...
I have a list of items that has contiguous repetitions of values, but
the number and location of the repetitions is not important, so I just
need to strip them out. For example, if my original list is
[0,0,1,1,1,2,2,3,3,3,2,2,2,4,4,4,5], I want t
ow (instead of waiting for a future
version of Python, assuming it's accepted), the current code for the
Bunch class follows.
STeVe
--
# Copyright (c) 2004 Python Software Foundation.
# All rights reserved.
# Written by Steven
rbt wrote:
Either I'm crazy and I'm missing the obvious here or there is something
wrong with this code. Element 5 of this list says it doesn't contain the
string 255, when that's *ALL* it contains... why would it think that???
import time
ips = ['255.255.255.255', '128.173.120.79', '198.82.247.
Steve Holden wrote:
You are modifying the list as you iterate over it. Instead, iterate over
a copy by using:
for ip in ips[:]:
...
Also worth noting, you can write this like:
for ip in list(ips):
...
if you're afraid of smiley-faces [:] in your code. ;)
Steve
--
http://mail.python.
Fredrik Lundh wrote:
Steven Bethard wrote:
Raymond Hettinger wrote:
return max(lst)
Very clever! Thanks!
too clever. boolean > None isn't guaranteed by the language specification:
Yup. I thought about mentioning that for anyone who wasn't involved in
the previous thread di
rbt wrote:
John J. Lee wrote:
Steve Holden <[EMAIL PROTECTED]> writes:
[...]
You are modifying the list as you iterate over it. Instead, iterate
over a copy by using:
for ip in ips[:]:
...
Just to help popularise the alternative idiom, which IMO is
significantly less cryptic (sane constructors of
Nick Coghlan wrote:
Steven Bethard wrote:
Yes -- help me rally behind my generic object PEP which proposes a
Bunch type (probably to be renamed) for the Python standard lib. =)
Did you see the suggestion of 'namespace' as a name?
Yup, it's in the current PEP draft. See the "
Nick Coghlan wrote:
Alex Martelli wrote:
Nick Coghlan <[EMAIL PROTECTED]> wrote:
...
Michael Spencer also posted an interesting idea recently about
setting up
a view of an existing dictionary, rather than as a separate object:
class attr_view(object):
def __init__(self, data):
object.__s
fortepianissimo wrote:
Thanks Steve - actually my question was simpler than that. I just
wanted to use Daniels' recipe of lazy initialization on objects with
__slots__:
class Lazy(object):
def __init__(self, calculate_function):
self._calculate = calculate_function
def __get__(self,
Alex Martelli wrote:
Steven Bethard <[EMAIL PROTECTED]> wrote:
Here's a solution that works for iterables other than lists:
py> def collapse(iterable):
... enumeration = enumerate(iterable)
... _, lastitem = enumeration.next()
... yield lastitem
... for i, item
nition among software purchasers and IT
departments; and it was (usually) a future sale to Microsoft.
It was only as Microsoft approached monopoly status that copyright
infringement began to hurt them more than it gained them. With few if any
competitors, the loss of revenue from unauthorized copie
On Sat, 18 Jun 2005 15:43:24 -0400, Chinook wrote:
> Steven,
>
> Your weigh-in on semantics is misleading,
How is it misleading?
> but your elaboration of the aspect is very well put.
>
> As to semantics, piracy is to the originator what freedom fighter is to thos
In Han Kang wrote:
> Anyway, I was wondering...I have an super class which is the superclass
> for 5 other classes. However, I want to be able to call the subclass
> constructors from the super class. Is this possible?
Are you trying to use your superclass as a factory?
If so, one option is s
In Han Kang wrote:
> So each of the sub classes plots a different type of graph. The
> superclass defines methods that are the same for all the plots. I want
> to be able to pick some points and be able to generate a more plots.
> What I was wondering if I could define in a method in the supe
[EMAIL PROTECTED] wrote:
> I know this is wrong syntax, but I think it demonstrates what I'm
> trying to do:
>
> import myModule path = /modules/myModule
> import myModule2 path = /modules/myModule2
>
> Something like that. Is it possible?
I would put your additional modules into a 'modules' di
Charles Krug wrote:
> myWords = split(aString, aChar)
>
> is depreciated but
>
> myWords = aString.split(aChgar)
>
> is not?
Yes, that's basically correct. What's deprecated are the functions in
the string module. So
string.split(a_str, b_str)
is deprecated in favor of
a_str.split
[EMAIL PROTECTED] wrote:
> AhhI see. I played around with the sys.path function...and it
> looks like python automatically looks in the same directory as my
> script first. Then is searches to all the other pre-defined paths. So
> it works for me to just keep my main script in the same direc
Oliver Andrich wrote:
> def remove_html_entities(data):
> for html, char in html2text:
> data = apply(string.replace, [data, html, char])
> return data
I know this isn't your question, but why write:
> data = apply(string.replace, [data, html, char])
when you could write
data
James Stroud wrote:
> Hello All,
>
> Is this a bug? Why is this tuple getting unpacked by raise? Am I missing some
> subtle logic? Why does print not work the same way as raise? Both are
> statements. Why does raise need to be so special?
>
> py> sometup = 1,2
> py> print sometup
> (1, 2)
> py>
tter way of putting what James tried to get across is, don't
be too concerned about writing fast code until you have learnt the
basics of the language. Get the code WORKING first, and FAST second.
(And frequently, the best way to get it working is also the best way to
have it run fast.)
--
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i in dummies: funString += i + ','
> funString = funString[0:len(funString)-1]
> funString += ')'
> loopStr= '[ ' + funString
> for i in range(0,dim):
> loopStr += ' for ' + dummies[i] + ' in Range(' +
> r
Grig Gheorghiu wrote:
import codecs
print codecs.encode(c, 'utf-8')
>
> © some text
Or simply:
py> print c.encode('utf-8')
© some text
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h risk. It also relies on an implementation detail, that True
and False are singletons (doubletons?), and will break if that changes.
And finally, since True is just an object, and not a constant like None,
it will break if True gets set to some other value.
In other words, it is not only superfluous but also fragile.
--
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On Wed, 22 Jun 2005 09:54:44 +0200, Fredrik Lundh wrote:
>> [CENSORED] I keep for myself how stupid I found your post.
>
> so let's see if everyone who understands how embarrassingly stupid
> your post is will keep that to themselves...
Damn, did I fail some test?
-
I thought I was just calling other functions :-)
That's the joys of a mostly self-taught programming knowledge: you miss
out on all the buzzwords.
--
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which act
in a similar way, you would say
try:
False
except NameError:
False = 0
True = not False
Note that there is no need to do something with the name "False" in the
try clause -- just use it.
--
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--
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because the test did atan2 on the
> components of an all-zero complex raised to an integer power, and I
> had written one of the few 754-conforming libms at the time. They
> wanted 0, while my atan2 dutifully returned -pi. I haven't had much
> personal love for 75
Steve Juranich wrote:
> I have in some code an 'eval', which I hate, but it's the shortest
> path to where I need to get at this point.
What's this code trying to do? If you care about malicious code at all,
you'll avoid 'eval' completely. A couple reasons why:
With only a little trouble, I ca
return self.value
(only with error checking etc for production code).
Then you use it like this:
py> myprintablestr = MyClass("Lovely Spam!")
py> print myprintablestr
*** Lovely Spam!!! ***
Am I close?
--
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Tim Peters wrote:
> [Steven D'Aprano]
>>It isn't necessary to look at complex numbers to see the difference
>>between positive and negative zero. Just look at a graph of y=1/x. In
>>particular, look at the behaviour of the graph around x=0. Now tell me
>>
ount of your target;
- try to avoid adding or subtracting numbers of wildly
differing magnitudes; and
- be aware of the risk of errors blowing out and have
strategies in place to manage the size of the error.
--
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.blue := 255; colour.green := 0;
Okay, so maybe it is more of a feature than a trick, but I miss it and it
would be nice to have in Python.
--
Steven
--
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from Pascal
with self:
blue = blue
green = green
red = red
And now you can see why Python doesn't support this idiom.
--
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There's an easy way to settle this once and for all. If somebody can come
up with a good empirical test for "easier" (easier what?), we can run
some tests, get some hard figures for, eg, how many calories are expended
in typing one form over the other, and find out which is easier.
Until then, the question is at least partly a matter of personal taste,
and as such, there is no justification for such sweeping generalities as
"the answer is simply no, just use an if statement instead".
--
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Matthew Thorley wrote:
> from elementtree import ElementTree as et
>
> xmla = et.ElementTree('some_file.xml')
> xmlb = et.Element('parent')
> et.SubElement(xmlb, 'child1')
> et.SubElement(xmlb, 'child2')
>
> root = et.Element('root')
> root.append(xmla.getroot())
> root.append(xmlb)
>
> print et
[EMAIL PROTECTED] wrote:
> Apologies if this question seems stupid: How does one write a
> function that increments a value in Python? When I tried, the variable
> never changed.
> The session went like this:
>
def incr(counter):
> counter = int(counter)
> counter += 1
>
cou
doesn't exactly fit the specification but may
> be easier to read.
Or, more generally,
[0 for x in L if x is None]
which doesn't solve the asked-for question, but is a useful feature.
--
Steven.
--
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old the entire list in memory.
> 2.) Contracts
Explain please.
> 3.) With
Explain please.
--
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--
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On Fri, 24 Jun 2005 15:47:45 -0700, James Stroud wrote:
> On Friday 24 June 2005 05:58 am, Steven D'Aprano wrote:
>> with colour do begin
>> red := 0; blue := 255; green := 0;
>> end;
>>
>> instead of:
>>
>> colour.red := 0; colour.blue := 255;
):
> counter = int(counter)
> counter += 1
>
>>>> counter = 1
>>>> incr(counter)
>>>> print counter
> 1
Why does it need to be a function? Why complicate matters? Isn't it
simpler to just do this:
counter = 1
counter += 1
print counter
--
Steven
--
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x for initialising dicts conflicts with the use of keyword
arguments for non-existent, hypothetical and/or user-defined classes.
That's okay. I'm perfectly comfortable with the fact that the syntax for
initialising a dict conflicts with the syntax for initialising a list, a
Decimal, a MutableString, and a ConfigParser object.
So why should I be distressed that it conflicts with the syntax for
initialising MyDictWithDefaultValue objects?
--
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On Sat, 25 Jun 2005 17:41:58 +0200, Konstantin Veretennicov wrote:
> On 6/25/05, Mandus <[EMAIL PROTECTED]> wrote:
>> It is really a consensus on this; that
>> removing map, filter, reduce is a good thing? It will render a whole lot
>> of my software unusable :(
>
> I think you'll be able to use
[The HTML version of this Summary is available at
http://www.python.org/dev/summary/2005-05-01_2005-05-15.html]
=
Summary Announcements
=
--
PEP 340 Episode 2: Revenge of the With (Block)
-
[The HTML version of this Summary is available at
http://www.python.org/dev/summary/2005-05-16_2005-05-31.html]
=
Summary Announcements
=
QOTF
We have our first ever Quote of the Fortnight (QOTF), thanks to
the wave of discussion over `PEP 343`_
[The HTML version of this Summary is available at
http://www.python.org/dev/summary/2005-06-01_2005-06-15.html]
=
Summary Announcements
=
-
Bug Day: Saturday, June 25th 2005
-
AMK organized an
>>>> list comprehensions a bit better.
>>>>
>>
>>
>> Couldnt there just be a "functional" module ?...
>>
>> from functional import map, filter, reduce
>
> but lambda is grammar, so probably not so easy to import?
"from __future
On Sat, 25 Jun 2005 15:44:14 -0400, Nicolas Fleury wrote:
> Steven D'Aprano wrote:
>> One of the things I liked in Pascal was the "with" keyword. You could
>> write something like this:
>>
>> with colour do begin
>> red := 0; blue := 255; green :=
ile our code every single time to know this?
Isn't it reasonable to just say, "I use join because it is faster than
adding strings" without being abused for invalid optimization?
--
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--
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omments suggest to me that they are safe until list comps are
significantly faster. But reduce needs to be re-factored as a for loop,
with all the disadvantages that implies. I think that if people like
Mandus have good real-world usage cases for reduce, it can be saved, at
least as part of
hold the intermediate
results of from the for loop. Yes, that seems to be the case."
Funny how people differ in what they find readable :-)
--
Steven.
--
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On Sat, 25 Jun 2005 18:44:12 -0700, James Stroud wrote:
> On Saturday 25 June 2005 11:08 am, Steven D'Aprano wrote:
>> The problem is, you have made colour (returning to English spelling
>> instead of foreign) into a class. If you need two colour variables, you
>> have
On Sat, 25 Jun 2005 23:08:10 +, Bengt Richter wrote:
> On Sun, 26 Jun 2005 04:08:31 +1000, Steven D'Aprano <[EMAIL PROTECTED]> wrote:
>
>>On Fri, 24 Jun 2005 15:47:45 -0700, James Stroud wrote:
>>
>>> On Friday 24 June 2005 05:58 am, Steven D'Apran
here, ;-/
Given how much the use of global variables are discouraged, is it a
good idea to allow even more inter-namespace interactions?
--
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ever throws an exception
> (unless the parameter list has the wrong types). Its an example of a
> method that can be used cleanly with a type inferencer, while the index
> and find methods cannot.
Er, how does that last one work? How can findall be used cleanly? Why
can't find?
--
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, easy to understand examples of where
Python's name/object model differs from the variable/value model?
--
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exchanging one special case for another
special case.
> The result of find() does
> not have this property: it can be an integer that is an index into the
> string,
> or it can be a -1.
Both of which are ints. What you are talking about isn't really TYPE
checking, but more like
do assignment like this:
>
> a, b = (1,)*2
>
> But I guess that's not exactly elegant. ;-)
In general that is not the same thing as a = b = obj.
py> a, b = ([], [])
py> a.append(1)
py> b
[]
py> a = b = []
py> a.append(1)
py> b
[1]
--
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The history and justification for Hungarian notation is explained here:
http://www.joelonsoftware.com/articles/Wrong.html
--
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Reinhold Birkenfeld wrote:
> For my part, ctypes seems like a suggestion to start with.
I believe this has been discussed somewhere before and the conclusion
was that ctypes should not be a candidate for inclusion in the Python
stdlib because people don't want things in the stdlib that can make
Fredrik Johansson wrote:
> On 6/27/05, Reinhold Birkenfeld <[EMAIL PROTECTED]> wrote:
>
>>Do you have any other good and valued Python modules that you would think are
>>bug-free, mature (that includes a long release distance) and useful enough to
>>be granted a place in the stdlib?
>
> First of
[EMAIL PROTECTED] wrote:
> if type(input) == str:
You might consider writing this as:
if isinstance(input, basestring):
I don't know if pyparsing ever produces unicode objects, but in case it
does (or it starts to in the future), isinstance is a better call here.
STeVe
--
http://mail
in a la-bor-atory, not a lab-rat-ory, even if they have
lab rats in the laboratory.
Fans of the X-Men movies and comics will remember Professor Charles
Xavier. Unless you are Spanish (Kh-avier), the X sounds like a Z: Zaviour.
But never never never Xecks-Aviour or Eggs-Savior.
Nuclear. Say no more.
--
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Rahul wrote:
> def wrapper(obj):
>g = obj.__call__
>def f(*args,**kwargs):
> for arg in args:print arg
> return g(*args,**kwargs)
>obj.__call__=f
> but it seems this will not work for functions :(
def wrap(obj):
def f(*args, **kwargs):
for arg in args:
Noah wrote:
> def unzip(list):
> if len(list) == 0: return ()
> l = []
> for t in range(len(list[0])):
> l.append(map( lambda x,t=t: x[t], list ))
> return tuple(l)
The simplest solution to this problem that I know of:
def unzip(iterable):
return zip(*iterabl
Steven Bethard wrote:
>
> def wrap(obj):
> def f(*args, **kwargs):
> for arg in args:
> print arg
> return obj(*args, **kwargs)
> return f
>
> @wrap
> def func(a, b, c):
> ...
>
> class C(object):
>
Fuzzyman wrote:
> Surely when they are removed :
>
> class foo:
> pass
>
> won't become invalid syntax, it will just automatically inherit from
> object ?
Well, Guido views this particular syntax as an "oopsie"[1]. It should
actually look like:
class C():
pass
Guido also su
I have a string with a bunch of whitespace in it, and a series of chunks
of that string whose indices I need to find. However, the chunks have
been whitespace-normalized, so that multiple spaces and newlines have
been converted to single spaces as if by ' '.join(chunk.split()). Some
example d
John Machin wrote:
> If "work" is meant to detect *all* possibilities of 'chunks' not having
> been derived from 'text' in the described manner, then it doesn't work
> -- all information about the positions of the whitespace is thrown away
> by your code.
>
> For example, text = 'foo bar', chun
from the context:
def stepsum(n, step=1):
total = 0
for i in range(0, n, step):
total + i
return total
def add_colon_str(s, t):
return s + ": " + t
It doesn't need much explanation to understand what s
and t are. But for anything more complex, I always use
descriptive names.
--
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John Machin wrote:
> Steven Bethard wrote:
>
>> John Machin wrote:
>>
>>> For example, text = 'foo bar', chunks = ['foobar']
>>
>> This doesn't match the (admittedly vague) spec
>
> That is *exactly* my point -- it is not val
Chinook wrote:
> >>> ta = [5, 15, 12, 10, 9]
> >>> for i in range(len(ta)):
> ... if ta[i] >= 10:
> ... ta[i] -= 10
> ... else:
> ... ta[i] += 10
> ...
> >>> ta
> [15, 5, 2, 0, 19]
One possibility:
py> [(tai + 10, tai - 10)[tai >= 10] for tai in ta]
[15, 5, 2, 0, 19]
But see:
htt
[EMAIL PROTECTED] wrote:
> I avoid map sometimes, because I find its syntax less readable
> than list (and expression) comprehensions. But occasionally it
> is the most readable way to do something, and I wouldn't want to lose
> it.
I tend to avoid map as much as possible. The only places I'm sti
Peter Otten wrote:
> import re
> _reLump = re.compile(r"\S+")
>
> def indices(text, chunks):
> lumps = _reLump.finditer(text)
> for chunk in chunks:
> lump = [lumps.next() for _ in chunk.split()]
> yield lump[0].start(), lump[-1].end()
Thanks, that's a really nice, clean s
Bengt Richter wrote:
> I wonder if the above common use of super could be implemented as a property
> of object,
> so you'd normally inherit it and be able to write
> self.super.__init__(*args, **kwargs) # (maybe spell it
> self.__super__.__init__(...) I suppose)
>
> I.e., self.__super__ wo
o know.
--
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On Fri, 01 Jul 2005 09:13:58 -0700, mcherm wrote:
> Lambda serves a very specific purpose: declaring small, in-place
> functions which are no bigger than a single expression. I do this often
> enough that I DO want special syntax for it. But I'll admit that I
> wish "lambda" were about 5 or 6 cha
that demonstrated that this made a
significant -- or even measurable -- speed-up in anything but the most
unusual cases.
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to be moved into a module rather
than dropped altogether. Provided list comps are made as fast as map and
filter, then at the cost of readability they can be replaced by list
comps. But reduce can't be written as a list comp, only as a relatively
complex for loop at a HUGE loss of rea
Guido seems to like list
comprehensions. Unless I'm mistaken (not for the first time) I think he
actually introduced them to the language. They won't be going anywhere
anytime soon.
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e it this way:
rand_nums = four_random()
# rand_nums is a list of four numbers
print rand_nums[0] # prints the first random number
print rand_nums[3] # prints the last one
or like this:
alpha, beta, gamma, delta = four_random()
# four names for four separate numbers
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0 for any non-zero N
return 0.0
else:
return math.exp(math.log(x)/y)
Note how much simpler this would be if we could guarantee proper
infinities and NaNs in the code. We could turn a 23-line block to a
one-liner.
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of reduce.
> Also, map is easily replaced.
> map(f1, sequence) == [f1(element) for element in sequence]
Three mental tokens ( map, f1, sequence ) versus seven ( [], f1, element,
for, element, in, sequence ).
Also, map can take any number of sequences:
map(f1, seq1, seq2, seq3, seq4, ...
common ones.
Er, excuse me, but that is EXACTLY what Devan claimed.
Quote: "With the exception of reduce(lambda x,y:x*y, sequence), reduce can be
replaced with sum, and Guido wants to add a product function."
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ps2'
> why does it happen?
It works for me.
>>> import sys
>>> sys.ps2
'... '
Can you cut and past the relevant lines from your interactive session?
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On Sun, 03 Jul 2005 10:56:42 +0100, Tom Anderson wrote:
> On Sun, 3 Jul 2005, Steven D'Aprano wrote:
>
>> On Sun, 03 Jul 2005 02:22:23 +0200, Fredrik Johansson wrote:
>>
>>> On 7/3/05, Tom Anderson <[EMAIL PROTECTED]> wrote:
>>>> Tha
od reason for it, though.
Yes. You generally want exponentiation to have the highest precedence.
2*3**4 should give 162, not 1296. Think about how you would write
that mathematically, with pencil and paper: the 4 is written as a
superscript over the 3, and is applied to that before multiplying by the 2.
Unary minus is equivalent to multiplying by -1, so -3**4 is equivalent to
-1*3**4.
These are the rules of precedence mathematicians have worked out over many
centuries. Yes, some of them are arbitrary choices, but they do work, and
changing them for another arbitrary choice doesn't give us any benefit.
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urreal. Reduce etc *work*,
right now. They have worked for years. If people don't like them, nobody
is forcing them to use them. Python is being pushed into directions which
are *far* harder to understand than map and reduce (currying, decorators,
etc) and people don't complain about those. And yet something as simple
and basic as map is supposed to give them trouble? These are the same
people who clamoured for zip, which is just a special case of map?
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On Sun, 03 Jul 2005 19:19:05 +, Bengt Richter wrote:
> On Sun, 03 Jul 2005 11:47:07 +1000, Steven D'Aprano <[EMAIL PROTECTED]> wrote:
>
>>On Fri, 01 Jul 2005 12:59:20 -0400, François Pinard wrote:
>>
>>> [Peter Hansen]
>>>> Mike Meyer wrote:
Because that is far less readable, and you take a performance hit.
> But I suspect that most people would just do what I currently do and
> write the for-loop to do what they want directly instead of using lambda
> in reduce.
That's your choice. I'm not suggesting we remove for loops and force you
to use reduce. Or even list comps.
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Christopher Subich wrote:
> One caevat that I just noticed, though -- with the for-solution, you do
> need to be careful about whether you're using a generator or list if you
> do not set an explicit initial value (and instead use the first value of
> 'sequence' as the start). The difference is
ill say this.
Practicality beats purity. If you can demonstrate a
good usage case for testing equality with NaNs, I will
accept that it is a good thing to do.
if x in (SOME_NAN, SOME_OTHER_NAN, ANOTHER_NAN, \
YET_ANOTHER_NAN, AND_ANOTHER_NAN, ..., \
# 240+ more NaNs listed
ALMOST_FINISHED_NOW, LAST_NAN):
print "Calculation failed!"
is _not_ a good usage case, since it is best handled with:
if isNan(x): # handled by the floating point package
print "Calculation failed!"
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