[Tutor] Polyfit works like this
On Tuesday 01 December 2009, questions anon wrote: > I would now like to add a line of best fit. I think the command is > polyfit()?? > But I can't seem to get it to work These are the steps to make polyval work. I typed it into an 'ipython -pylab' session; I hope I included all relevant lines and I removed some of the output: #this is the input data In [13]:d_x = [0, 0.1, 0.3, 0.5, 0.7, 1, 1.2, 1.5, 1.8, 2] In [14]:d_y = [0.1, 0.11, 0.15, 0.3, 0.5, 0.8, 1, 1.2, 1.1, 1.2] #show input data In [15]:plot(d_x,d_y, label='data') #make 2nd degree polynom, and plot smoothly with 50 points In [17]:pol2 = polyfit(d_x, d_y, 2) In [18]:p_x = linspace(0, 2, 50) In [19]:p2_y = polyval(pol2, p_x) In [20]:plot(p_x,p2_y, label='pol 2nd') #also create line and plot it too (would not need 50 points) In [21]:pol1 = polyfit(d_x, d_y, 1) In [22]:p1_y = polyval(pol1, p_x) In [24]:plot(p_x,p1_y, label='line') #create legend so you can recognize the curves In [25]:legend() Eike. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] Fwd: Moving from Python 2 to Python 3: A 4 page "cheat sheet"
Forwarded from python-announce. A helpful summary of the differences between Python 2 and 3 (though some of the differences were introduced well before Python 3). Kent -- Forwarded message -- From: Mark Summerfield To: comp-lang-python-annou...@moderators.isc.org Date: Tue, 1 Dec 2009 06:05:09 -0800 (PST) Subject: Moving from Python 2 to Python 3: A 4 page "cheat sheet" I've produced a 4 page document that provides a very concise summary of Python 2<->3 differences plus the most commonly used new Python 3 features. It is aimed at existing Python 2 programmers who want to start writing Python 3 programs and want to use Python 3 idioms rather than those from Python 2 where the idioms differ. It uses Python 3.1 syntax since that looks like being the standard for a few years in view of the language moratorium. The document is U.S. Letter size but will also print fine on A4 printers. It is available as a free PDF download (no registration or anything) from InformIT's website. Here's the direct link: http://ptgmedia.pearsoncmg.com/imprint_downloads/informit/promotions/python/python2python3.pdf And of course, if you want more on Python 3, there's always the documentation---or my book:-) "Programming in Python 3 (Second Edition)" ISBN-10: 0321680561. -- Mark Summerfield, www.qtrac.eu ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Moving from Python 2 to Python 3: A 4 page "cheatsheet"
"Kent Johnson" wrote Forwarded from python-announce. A helpful summary of the differences between Python 2 and 3 (though some of the differences were introduced well before Python 3). It is available as a free PDF download (no registration or anything) from InformIT's website. Here's the direct link: http://ptgmedia.pearsoncmg.com/imprint_downloads/informit/promotions/python/python2python3.pdf It didn't work for me I always got forwarded to the Book "home page" on InformIT Alan G ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] pygame help with livewires
ok so its working and drops a normal cow and randomly a green cow but
i want it to be able to tell when you collide with the green cow cause
its gonna be a powerup.
heres the code for my program.
# Pizza Panic
# Player must catch falling pizzas before they hit the ground
from livewires import games, color
import random
hscorefile = open("hscores.txt", 'r')
score = 0
level = 1
pizzascore = 2
stl = 15
lstl = 15
pizza_speed = 1
cook_speed = 4
pizza_drop = 0.5
level_up_drop = 1
highscore = int(hscorefile.read(1))
hscorefile.close()
games.init(screen_width = 640, screen_height = 480, fps = 50)
class Pan(games.Sprite):
"""
A pan controlled by player to catch falling pizzas.
"""
global score
image = games.load_image("pan.bmp")
def __init__(self):
""" Initialize Pan object and create Text object for score. """
global level
global hs
global score
super(Pan, self).__init__(image = Pan.image, x =
games.mouse.x, bottom = games.screen.height)
self.score = games.Text(value = 0, size = 25, color = color.black,
top = 5, right = games.screen.width - 10)
games.screen.add(self.score)
self.leveltxt = games.Text(value = "level:", size = 25, color
= color.black,
top = 5, right = games.screen.width - 580)
games.screen.add(self.leveltxt)
self.level = games.Text(value = level, size = 25, color = color.black,
top = 5, right = games.screen.width - 566)
games.screen.add(self.level)
self.hs = games.Text(value = "Highscore:" + str(highscore),
size = 25, color = color.black,
top = 5, right = games.screen.width - 320)
games.screen.add(self.hs)
def update(self):
""" Move to mouse x position. """
self.x = games.mouse.x
if self.left < 0:
self.left = 0
if self.right > games.screen.width:
self.right = games.screen.width
self.check_catch()
def check_catch(self):
""" Check if catch pizzas. """
global pizza_drop
global level
global score
global score_to_level
global cook_speed
global pizza_speed
global stl
global lstl
global pizzascore
stl = (lstl *2.5)
for pizza in self.overlapping_sprites:
self.score.value = self.score.value + pizzascore
score = self.score.value
if self.score.value >= stl:
lstl = stl
pizza_drop += 0.2
self.level.value += 1
pizza_speed += .25
pizzascore = pizzascore * 2
cook_speed += 5
level = level + 1
lvlup_message = games.Message(value = "Level " + str(level),
size = 90,
color = color.red,
x = games.screen.width/2,
y = games.screen.height/2,
lifetime = 2 * games.screen.fps)
games.screen.add(lvlup_message)
self.score.right = games.screen.width - 10
pizza.handle_caught()
class Pizza(games.Sprite):
"""
A pizza which falls to the ground.
"""
global pizza_speed
speed = 1.5
image = games.load_image("pizza.bmp")
def __init__(self, x, y = 90):
""" Initialize a Pizza object. """
super(Pizza, self).__init__(image = Pizza.image,
x = x, y = y,
dy = pizza_speed)
def update(self):
""" Check if bottom edge has reached screen bottom. """
if self.bottom > games.screen.height:
self.end_game()
self.destroy()
def handle_caught(self):
""" Destroy self if caught. """
self.destroy()
def end_game(self):
global highscore
global score
global name
""" End the game. """
if score > highscore:
hsfile = open("hscores.txt", "w")
hsfile.write(str(score))
hsfile.close()
hs_message = games.Message(value ="New highscore of " + str(score),
size = 45,
color = color.red,
x = games.screen.width/2,
y = games.screen.height/2,
lifetime = 1 * games.screen.fps,
after_death = games.screen.quit)
games.screen.add(hs_message)
else:
end_message = games.Message(value = "game over",
size = 45,
color = color.red,
x = games.screen.width/2,
y =
Re: [Tutor] Moving from Python 2 to Python 3: A 4 page "cheatsheet"
On Wed, Dec 2, 2009 at 8:56 AM, Alan Gauld wrote: > > "Kent Johnson" wrote > >> Forwarded from python-announce. A helpful summary of the differences >> between Python 2 and 3 (though some of the differences were introduced >> well before Python 3). > >> It is available as a free PDF download (no registration or anything) >> from InformIT's website. Here's the direct link: >> >> http://ptgmedia.pearsoncmg.com/imprint_downloads/informit/promotions/python/python2python3.pdf > > > It didn't work for me I always got forwarded to the Book "home page" on > InformIT Strange. Worked for me yesterday and again just now. Kent ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Moving from Python 2 to Python 3: A 4 page "cheatsheet"
* Alan Gauld [091202 15:07]: > >http://ptgmedia.pearsoncmg.com/imprint_downloads/informit/promotions/python/python2python3.pdf > > > It didn't work for me I always got forwarded to the Book "home page" > on InformIT Worked for me with wget(1). -- You are capable of planning your future. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Moving from Python 2 to Python 3: A 4 page "cheatsheet"
On Wed, Dec 2, 2009 at 8:13 AM, Joerg Woelke wrote: > Alan Gauld [091202 15:07]: > > > > http://ptgmedia.pearsoncmg.com/imprint_downloads/informit/promotions/python/python2python3.pdf > > > > > > It didn't work for me I always got forwarded to the Book "home page" > > on InformIT > Worked for me with wget(1). > And for me with Google Chrome on Ubuntu... -Wayne -- To be considered stupid and to be told so is more painful than being called gluttonous, mendacious, violent, lascivious, lazy, cowardly: every weakness, every vice, has found its defenders, its rhetoric, its ennoblement and exaltation, but stupidity hasn’t. - Primo Levi ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Moving from Python 2 to Python 3: A 4 page "cheatsheet"
Thanks 2009/12/3 Wayne Werner > > > On Wed, Dec 2, 2009 at 8:13 AM, Joerg Woelke wrote: > >> Alan Gauld [091202 15:07]: >> > > >> http://ptgmedia.pearsoncmg.com/imprint_downloads/informit/promotions/python/python2python3.pdf >> > >> > >> > It didn't work for me I always got forwarded to the Book "home page" >> > on InformIT >> Worked for me with wget(1). >> > > > And for me with Google Chrome on Ubuntu... > -Wayne > -- > To be considered stupid and to be told so is more painful than being called > gluttonous, mendacious, violent, lascivious, lazy, cowardly: every weakness, > every vice, has found its defenders, its rhetoric, its ennoblement and > exaltation, but stupidity hasn’t. - Primo Levi > > ___ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor > > ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
[Tutor] working with bit arrays
Hi, I am trying to represent a number as a list of bits: for example the bit representation of the integer 8. I did find a number of articles pertaining to a module called bitarray but I was unable to download/install that package. I am using Linux on Ubuntu 9.10; Python 2.6.2. I am almost certain there is a relatively easy way to convert an integer that can be represented by 32 bits into an array of bits that I can iterate over looking for switched on bits or switched off bits. Any information such as recipes or past articles in this list providing methods to create and manipulate bit arrays would be most appreciated. Robert ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] working with bit arrays
On Wed, Dec 2, 2009 at 12:08 PM, Robert Berman wrote:
> Hi,
>
> I am trying to represent a number as a list of bits: for example the bit
> representation of the integer 8. I did find a number of articles pertaining
> to a module called bitarray but I was unable to download/install that
> package. I am using Linux on Ubuntu 9.10; Python 2.6.2.
>
> I am almost certain there is a relatively easy way to convert an integer
> that can be represented by 32 bits into an array of bits that I can iterate
> over looking for switched on bits or switched off bits.
>
> Any information such as recipes or past articles in this list providing
> methods to create and manipulate bit arrays would be most appreciated.
>
Python 2.6+ (as far as I know) has the bin() function:
Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit (Intel)]
on
win32
Type "help", "copyright", "credits" or "license" for more information.
>>> bin(8)
'0b1000'
>>>
And larger:
>>> bin(999)
'0b10101001011010010110001110100101001100111'
You can convert them to integers to use ^ (XOR) or & (AND) and other binary
operations on them:
http://docs.python.org/reference/expressions.html#binary-bitwise-operations
>>> a = int('01001', 2)
>>> b = int('1', 2)
>>> a & b == b
True
>>> a = int('01110', 2)
>>> a & b == b
False
There may be some other way to check, but that's probably the easiest I know
of.
HTH,
Wayne
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Re: [Tutor] working with bit arrays
Wayne,
Thank you very much.
Robert
On Wed, 2009-12-02 at 12:48 -0600, Wayne Werner wrote:
> On Wed, Dec 2, 2009 at 12:08 PM, Robert Berman
> wrote:
>
> Hi,
>
> I am trying to represent a number as a list of bits: for
> example the bit representation of the integer 8. I did find a
> number of articles pertaining to a module called bitarray but
> I was unable to download/install that package. I am using
> Linux on Ubuntu 9.10; Python 2.6.2.
>
> I am almost certain there is a relatively easy way to convert
> an integer that can be represented by 32 bits into an array of
> bits that I can iterate over looking for switched on bits or
> switched off bits.
>
> Any information such as recipes or past articles in this list
> providing methods to create and manipulate bit arrays would
> be most appreciated.
>
>
>
> Python 2.6+ (as far as I know) has the bin() function:
>
>
> Python 2.6.2 (r262:71605, Apr 14 2009, 22:40:02) [MSC v.1500 32 bit
> (Intel)] on
> win32
> Type "help", "copyright", "credits" or "license" for more information.
> >>> bin(8)
> '0b1000'
> >>>
>
>
> And larger:
>
>
> >>> bin(999)
> '0b10101001011010010110001110100101001100111'
>
>
> You can convert them to integers to use ^ (XOR) or & (AND) and other
> binary operations on
> them:
> http://docs.python.org/reference/expressions.html#binary-bitwise-operations
>
>
> >>> a = int('01001', 2)
> >>> b = int('1', 2)
> >>> a & b == b
> True
> >>> a = int('01110', 2)
> >>> a & b == b
> False
>
>
> There may be some other way to check, but that's probably the easiest
> I know of.
>
>
> HTH,
> Wayne
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Re: [Tutor] working with bit arrays
My approach has been to store it as an array and then build the integer as needed. This code requires Python 2.5 or later. def bits2int(l): return sum([2**i if j else 0 for i,j in enumerate(l)]) To convert the other way: def int2bits(m, n): return [int(bool(m&(1<>= inc return i floating point is so messy and slow :) Cheers On Wednesday 02 December 2009 12:08, Robert Berman wrote: > Hi, > > I am trying to represent a number as a list of bits: for example the bit > representation of the integer 8. I did find a number of articles > pertaining to a module called bitarray but I was unable to > download/install that package. I am using Linux on Ubuntu 9.10; Python > 2.6.2. > > I am almost certain there is a relatively easy way to convert an integer > that can be represented by 32 bits into an array of bits that I can > iterate over looking for switched on bits or switched off bits. > > Any information such as recipes or past articles in this list providing > methods to create and manipulate bit arrays would be most appreciated. > > Robert ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Tutor Digest, Vol 70, Issue 5
,
> x = games.screen.width/2,
> y = games.screen.height/2,
> lifetime = 1 * games.screen.fps,
> after_death = games.screen.quit)
> games.screen.add(hs_message)
> else:
> end_message = games.Message(value = "game over",
> size = 45,
> color = color.red,
> x = games.screen.width/2,
> y = games.screen.height/2,
> lifetime = 0 * games.screen.fps,
> after_death = games.screen.quit)
> games.screen.add(end_message)
>
>
> class power_pizza1(games.Sprite):
> """
> A pizza which falls to the ground.
> """
> global pizza_speed
> speed = 1.5
> image = games.load_image("power_pizza1.bmp")
>
> def __init__(self, x, y = 90):
> """ Initialize a Pizza object. """
> super(power_pizza1, self).__init__(image = power_pizza1.image,
> x = x, y = y, dy = pizza_speed)
>
>
> def update(self):
> """ Check if bottom edge has reached screen bottom. """
> if self.bottom > games.screen.height:
> self.destroy()
>
> def handle_caught(self):
> """ Destroy self if caught. """
> self.destroy()
> class Chef(games.Sprite):
> """
> A chef which moves left and right, dropping pizzas.
> """
> global cook_speed
> image = games.load_image("chef.bmp")
>
> def __init__(self, y = 55, speed = 1000, odds_change = 55):
> """ Initialize the Chef object. """
> super(Chef, self).__init__(image = Chef.image,
> x = games.screen.width / 2,
> y = y,
> dx = cook_speed)
>
> self.odds_change = odds_change
> self.time_til_drop = 0
>
>
> def update(self):
> """ Determine if direction needs to be reversed. """
> if self.left < 0 or self.right > games.screen.width:
> self.dx = -self.dx
> elif random.randrange(self.odds_change) == 0:
> self.dx = -self.dx
>
> self.check_drop()
>
>
> def check_drop(self):
> rpp = 5
> """ Decrease countdown or drop pizza and reset countdown. """
> global pizza_drop
> if self.time_til_drop > 0:
> self.time_til_drop -= pizza_drop
> else:
> new_pizza = Pizza(x = random.randrange(40, 600))
> rpp = random.randrange(1, 5)
> if rpp == 3:
> power_pizza = power_pizza1 (x = random.randrange(40, 600))
> games.screen.add(power_pizza)
> else:
> games.screen.add(new_pizza)
>
> # set buffer to approx 30% of pizza height, regardless of
> pizza speed
> self.time_til_drop = int(new_pizza.height * 1.3 / Pizza.speed) + 1
>
>
> def main():
> """ Play the game. """
> wall_image = games.load_image("wall.jpg", transparent = False)
> games.screen.background = wall_image
>
> the_chef = Chef()
> games.screen.add(the_chef)
>
> the_pan = Pan()
> games.screen.add(the_pan)
>
> games.mouse.is_visible = False
>
> games.screen.event_grab = True
> games.screen.mainloop()
>
> # start it up!
> main()
>
>
> --
>
> Message: 4
> Date: Wed, 2 Dec 2009 10:13:25 -0500
> From: Kent Johnson
> To: Alan Gauld
> Cc: tutor@python.org
> Subject: Re: [Tutor] Moving from Python 2 to Python 3: A 4 page
> "cheatsheet"
> Message-ID:
> <1c2a2c590912020713l72b85952ka4d5b8f3d1e2a...@mail.gmail.com>
> Content-Type: text/plain; charset=ISO-8859-1
>
> On Wed, Dec 2, 2009 at 8:56 AM, Alan Gauld wrote:
>>
>> "Kent Johnson" wrote
>>
>>> Forwarded from python-announce. A helpful summary of the differences
>>> between Python 2 and 3 (though some of the differences were introduced
>>> well before Python 3).
>>
>>> It is available as a free PDF download (no registration or anything)
>>>
Re: [Tutor] working with bit arrays
On Wed, Dec 2, 2009 at 1:08 PM, Robert Berman wrote: > Hi, > > I am trying to represent a number as a list of bits: for example the bit > representation of the integer 8. I did find a number of articles pertaining > to a module called bitarray but I was unable to download/install that > package. I am using Linux on Ubuntu 9.10; Python 2.6.2. > > I am almost certain there is a relatively easy way to convert an integer > that can be represented by 32 bits into an array of bits that I can iterate > over looking for switched on bits or switched off bits. If all you want to do is test bits, you can do that directly using bit-wise logical operators & and |. There is no need to convert to a different representation. For example In [1]: 0xff & 4 Out[1]: 4 In [2]: 0xf0 & 4 Out[2]: 0 Kent ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Moving from Python 2 to Python 3
I don't know that you will reach Mark through this list, I forwarded his post from another list. There is some info on the book web site: http://www.qtrac.eu/py3book.html When replying to a digest, please - change the subject line to something relevant - don't quote the entire digest in your reply. Kent On Wed, Dec 2, 2009 at 2:15 PM, aivars wrote: > Mark, > I have the first edition of your book. What is the difference between > two editions? ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Moving from Python 2 to Python 3
>> I have the first edition of your book. What is the difference between >> two editions? i believe the 1st ed is 3.0 and the 2nd ed is 3.1 but haven't confirmed with him yet. -- wesley - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - "Core Python Programming", Prentice Hall, (c)2007,2001 "Python Fundamentals", Prentice Hall, (c)2009 http://corepython.com wesley.j.chun :: wescpy-at-gmail.com python training and technical consulting cyberweb.consulting : silicon valley, ca http://cyberwebconsulting.com ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] working with bit arrays
On Mi, 2009-12-02 at 13:08 -0500, Robert Berman wrote: > Hi, > > I am trying to represent a number as a list of bits: for example the > bit representation of the integer 8. I did find a number of articles > pertaining to a module called bitarray but I was unable to > download/install that package. I am using Linux on Ubuntu 9.10; Python > 2.6.2. > > I am almost certain there is a relatively easy way to convert an > integer that can be represented by 32 bits into an array of bits that > I can iterate over looking for switched on bits or switched off bits. If all you want is to treat integers as lists of bits, you could create a wrapper class around an integer and implement the __getitem__ and __setitem__ methods to make it behave like a list. Using the bitwise operators, you could make the setter actually modify the bit in question (you'd probably have to either make sure you only receive 1 or 0 as value or you could simply use booleans instead). For a challenge you could try to extend the built-in integer type this way. I'm not sure why you'd need to be able to address bits directly like that, though. Normally the bitwise &, |, << and >> should suffice for all intents and purposes. Making an ACTUAL lists of ACTUAL integers representing the bits would be overkill, though. We're talking several bytes worth of nulls to represent a single bit. I'm all for late optimisation, but this just doesn't feel right. Cheers, Alan ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] working with bit arrays
As`Kent Johnson pointed out, you don't need to convert anything to strings, etc. An integer _is_ a bit array, and individual bits can be tested using the bitwise operators. For your example, if A is an integer you can test bit 8 with: if A & (1 << 8): dosomething There is a simple example on the Python wiki at http://wiki.python.org/moin/BitArrays It uses an array of 32-bit integers as a bit array. The advantage of using 'bitarray' or one of the other packages on the Python Package Index is that they have implemented all of the slicing, etc. of Python lists, strings, etc. Using an array of 32 bit integers, you have to go to some trouble to slice out, say, bits 20 to 40. HTH, Gil ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] working with bit arrays
"Robert Berman" wrote I am trying to represent a number as a list of bits: for example the bit representation of the integer 8. Numbers are already represented as arrays of bits, thats how they are stored. I am almost certain there is a relatively easy way to convert an integer that can be represented by 32 bits into an array of bits that I can iterate over looking for switched on bits or switched off bits. You can do that using bitmasks. For example to extract the 4th bit use bit4 = value & 0x08# 0x08 = 1000 For bit 2 use bit2 = value & 0x02 # 0x02 = 0010 You can iterate over each bit using for index in range(number_of_bits): print "bit", index + 1, "is", int(bool(value & (2**index)))# int(bool()) prints 1/0 Or am I missing something? -- Alan Gauld Author of the Learn to Program web site http://www.alan-g.me.uk/ ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Moving from Python 2 to Python 3
"wesley chun" wrote i believe the 1st ed is 3.0 and the 2nd ed is 3.1 but haven't confirmed with him yet. I bought the 1st edition which is definitely 3.0. It was quite good I thought. I doubt I'll buy another edition just for the 3.1 uplift, but if he covers the new themed widgets in tkinter I might change my mind! :-) Alan G. ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] working with bit arrays
On 12/2/2009 4:10 PM GilJohnson said... Using an array of 32 bit integers, you have to go to some trouble to slice out, say, bits 20 to 40. I think I agree -- if in fact it's not impossible. Tell me that's a typo or take a moment to explain what I'm misunderstanding... Emile ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] working with bit arrays
Emille, I do think he meant bit 20 to 32 rather than 20 to 40. Unless, of course, he's dealing with a 64 bit word. I am delighted with all the help I have received on this topic and I am gleefully learning anding and oring, but not too much on the EOR side. Thanks again for all the assistance. Robert On Wed, 2009-12-02 at 17:17 -0800, Emile van Sebille wrote: > On 12/2/2009 4:10 PM GilJohnson said... > > > Using an array of 32 bit integers, you have to go to some > > trouble to slice out, say, bits 20 to 40. > > I think I agree -- if in fact it's not impossible. Tell me that's a > typo or take a moment to explain what I'm misunderstanding... > > Emile > > > ___ > Tutor maillist - Tutor@python.org > To unsubscribe or change subscription options: > http://mail.python.org/mailman/listinfo/tutor ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] Do you use unit testing?
Uncle Bob Martin has written a great post about TDD: http://blog.objectmentor.com/articles/2009/10/06/echoes-from-the-stone-age "Look, TDD is not my religion, it is one of my disciplines. It’s like dual entry bookkeeping for accountants, or sterile procedure for surgeons. Professionals adopt such disciplines because they understand the theory behind them, and have directly experienced the benefits of using them." The rest of the post is good too! Kent ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
Re: [Tutor] working with bit arrays
Robert Berman wrote: Emille, I do think he meant bit 20 to 32 rather than 20 to 40. Unless, of course, he's dealing with a 64 bit word. You posted out of order (top--osted). So I am forced to put my response elsewhere. I am delighted with all the help I have received on this topic and I am gleefully learning anding and oring, but not too much on the EOR side. Thanks again for all the assistance. Robert On Wed, 2009-12-02 at 17:17 -0800, Emile van Sebille wrote: On 12/2/2009 4:10 PM GilJohnson said... Using an array of 32 bit integers, you have to go to some trouble to slice out, say, bits 20 to 40. I think I agree -- if in fact it's not impossible. Tell me that's a typo or take a moment to explain what I'm misunderstanding... Emile Once you have an *array* of integers, you have much more than 32 bits to work with. For example, with an array of size 10, you now have 320 bits to work with. He's just pointing out that it's a little bit awkward to address a group of bits that are not all in the same int. So bits 5-20 would be easy, while bits 29-40 would be much harder. DaveA ___ Tutor maillist - Tutor@python.org To unsubscribe or change subscription options: http://mail.python.org/mailman/listinfo/tutor
