🌐 Mailman 3 August 2007 - Tutor - python.org

Send binary/hex data to a TCP socket
by Tod Haren July 19, 2011

July 19, 2011

I need to send a server at the other end of a socket a 36 byte "frame", where each byte represents a specific field in the custom data structure. (If there are any Ham operators reading this, I'm talking about the AGW Packet Engine) The documentation for the server says to initialize each field to a binary zero(0x00). How do I get a binary zero in Python? The next step is to send this all to the server and subsequently receive a similarly formated frame. A very basic frame looks something like this(modified from documentation): |00 00 00 00 4D 00 00 00 00 00 00 00 00 00 00 00 |....M........... |00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................ |00 00 00 00 |.... My problem is that hex(0) return '0x0' and hex(ord('M')) returns '0x4d'. If I concatonate these all together then the socket receives 109 bytes instead of 36. The documentation examples are in C++, so they are little help to me. The examples make use of the MoveMemory function for building the frames, but I'm clueless what that does. Pseudo code for the frame above: l = [] for i in xrange(36): l.append(hex(0)) l[4]=hex(ord('M')) d='' d=d.join(l) #I need some other data type to send besides a string! sock.send(d) #send the 36 bytes to the socket Any pointers or references would be greatly appreciated.

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Tracking time
by Michael Key Jan. 6, 2010

Jan. 6, 2010

I am trying to develop a project tracking program that would allow you to track hours and minutes spent on several different projects and store he data in a database for printing. Any help would be appreciated. Mike

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difflib.SequenceMatcher with get_matching_blocks is incorrect
by Thomas Nov. 5, 2007

Nov. 5, 2007

I'm trying to write a program to test someone's typing speed and show them their mistakes. However I'm getting weird results when looking for the differences in longer (than 100 chars) strings: import difflib # a tape measure string (just makes it easier to locate a given index) a = '1-3-5-7-9-12-15-18-21-24-27-30-33-36-39-42-45-48-51-54-57-60-63-66-69-72-75-78-81-84-87-90-93-96-99-103-107-111-115-119-123-127-131-135-139-143-147-151-155-159-163-167-171-175-179-183-187-191-195--200' # now with a few mistakes b = '1-3-5-7-l-12-15-18-21-24-27-30-33-36-39o42-45-48-51-54-57-60-63-66-69-72-75-78-81-84-8k-90-93-96-9l-103-107-111-115-119-12b-1v7-131-135-139-143-147-151-m55-159-163-167-a71-175j179-183-187-191-195--200' s = difflib.SequenceMatcher(None, a ,b) ms = s.get_matching_blocks() print ms [(0, 0, 8), (200, 200, 0)] Have I made a mistake or is this function designed to give up when the input strings get too long? Thanks in advance, Thomas

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problem resulting from installing 3.0
by Dick Moores Sept. 2, 2007

Sept. 2, 2007

XP, Python 2.5.1 I installed 3.0 alpha out of curiosity in a separate folder from 2.5.1. Then I found that both 2.5.1's IDLE and my main Python editor Ulipad would no longer open. My first idea was that the installation of 3.0 somehow changed my path. But it didn't. After uninstalling 3.0, and fiddling with the path and PYTHONPATH, IDLE and Ulipad now open, but the console opens first. The files executed are idle.pyw and ulipad.pyw. How can I get back to where I was before, without that annoying console opening? path: %SystemRoot%\system32;%SystemRoot%;%SystemRoot%\System32\Wbem;C:\Program Files\Microsoft SQL Server\90\Tools\binn\;E:\Program Files\IDM Computer Solutions\UltraEdit-32;E:\Program Files\QuickTime\QTSystem\;E:\Program Files\Subversion\bin PYTHONPATH: E:\Python25\;E:\PythonWork\;E:\Programs\Ulipad3.7\ And another question is, exactly what should go into PYTHONPATH? I've never been clear about that. Thanks, Dick Moores

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parsing response from SOAPpy request
by Sean Cronin Sept. 1, 2007

Sept. 1, 2007

I'm using SOAPpy to access weather data from the NOAA National Digital Forecast Database XML Web Service [1] and I've been having trouble figuring out how to parse the data. The response comes back as XML document but when I check it with type(result) it shows the the response is a string. Does anyone have any suggestions on getting relevant data? I've attached a sample SOAP response to this post. Thanks, -Sean

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Starting classes
by Ara Kooser Sept. 1, 2007

Sept. 1, 2007

Hello, I read Alan Gauld's and How to Think Like a Computer Scientist section on classes. So I tried to write a simple room class. My goal is to write a short text adventure using classes. Here is the code: class Area: def _init_(self, name, description): self.name = name def look(here): "Look around the place you are in" print here.description outside1 = Area("Outside") outside1.description = "You are standing outside with the town gate to your back" self.contents.append("dirt") look(bedroom) I get the following error. Traceback (most recent call last): File "/Users/ara/Documents/text_advent.py", line 11, in <module> outside1 = Area("Outside") TypeError: this constructor takes no arguments Do the outside1 = Area("Outside) need to be nested in the class or can they be outside of it? Thank you. Ara -- Quis hic locus, quae regio, quae mundi plaga. Ubi sum. Sub ortu solis an sub cardine glacialis ursae.

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Fw: Starting classes
by christopher.henk＠allisontransmission.com Aug. 31, 2007

Aug. 31, 2007

Oops, forgot to reply all. Chris Henk ----- Forwarded by Christopher Henk/US/ATD/GMC on 08/31/2007 04:55 PM ----- Christopher Henk/US/ATD/GMC 08/31/2007 04:13 PM To "Ara Kooser" <ghashsnaga(a)gmail.com> cc Subject Re: [Tutor] Starting classes The class definition will only have the methods and/or the variables in its definition. So these two functions make up your class class Area: def _init_(self, name, description): self.name = name def look(here): "Look around the place you are in" print here.description looking at the class code: your init function only has one underscore before and after init, you want two, that is why you are getting the error. def __init__(self, name, description): Also you are requiring two arguments to make an Area class, the name and the description. If you try to create an instance using only the name (as you do below) the interpreter will again raise an error. def look(here): "Look around the place you are in" print here.description Not sure if this works as is, I believe it depends on the interpreter, but it is customary to use the word self as the first parameter, and then also change here in the function body def look(self): "Look around the place you are in" print self.description Getting into the code below the class definition: >outside1 = Area("Outside") This will raise an error since you required two parameters to create an Area class and you only provide one. You can either add the description here or leave it off in the __init__ function. Since most likely every area will have a description , I would add it here. outside1 = Area("Outside","You are standing outside with the town gate to your back") outside1.description = "You are standing outside with the town gate to your back" (see above, and below) self.contents.append("dirt") Here we have two problems. The first is the class doesn't have the "contents" attribute yet That's only a problem since you are trying to call a function with it. When you assign to an attribute (like with "description" in the line above), you are adding the attribute to you class instance ("outside1"), however you need to add it before you can use it. Second, you only use self from within the function definition. In this case you would want to use outside1.contents. look(bedroom) Since look was defined in the class definition, you would want to call it like this. bedroom.look() But as of right now there is no bedroom created, so this will give an error. however you can instead look outside. outside1.look() Looking at your code I would have a class something like this: class Area: #what does an area have that makes it an area? contents=None name=None description=None paths=None #where you can go def __init__(self, name, description): #define what everything will start as self.name = name self.discription=None self.contents=[] self.paths={} #Methods: #what can you do to an Area? def look(self): "Look around the place you are in" print self.description def addSomething(self,thing): "adds something to the contents" def removeSomething(self,thing) "remove from contents" def addPath(self,direction,area) "Adds a connection to area" #... #more as needed Chris Henk "Ara Kooser" <ghashsnaga(a)gmail.com> Sent by: tutor-bounces(a)python.org 08/31/2007 03:06 PM To tutor(a)python.org cc Subject [Tutor] Starting classes Hello, I read Alan Gauld's and How to Think Like a Computer Scientist section on classes. So I tried to write a simple room class. My goal is to write a short text adventure using classes. Here is the code: class Area: def _init_(self, name, description): self.name = name def look(here): "Look around the place you are in" print here.description outside1 = Area("Outside") outside1.description = "You are standing outside with the town gate to your back" self.contents.append("dirt") look(bedroom) I get the following error. Traceback (most recent call last): File "/Users/ara/Documents/text_advent.py", line 11, in <module> outside1 = Area("Outside") TypeError: this constructor takes no arguments Do the outside1 = Area("Outside) need to be nested in the class or can they be outside of it? Thank you. Ara -- Quis hic locus, quae regio, quae mundi plaga. Ubi sum. Sub ortu solis an sub cardine glacialis ursae. _______________________________________________ Tutor maillist - Tutor(a)python.org http://mail.python.org/mailman/listinfo/tutor

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or synxtax in if statement
by David Bear Aug. 31, 2007

Aug. 31, 2007

I think I want to be lazy and express this if a == b | a = c (if a equal b or a equals c) using if a == b | c it seems to work.. but I'm not sure if it is correct -- and I haven't seen any documentation on using this type of syntax. -- -- David Bear College of Public Programs at Arizona State University

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Formatting output into columns
by Scott Oertel Aug. 31, 2007

Aug. 31, 2007

Someone asked me this question the other day, and I couldn't think of any easy way of printing the output besides what I came up with pasted below. So what you have is a file with words in it as such: apple john bean joke ample python nice and you want to sort and output the text into columns as such: a p j b n apple python john bean nice ample joke and this is what works, but I would also like to know how to wrap the columns, plus any ideas on a better way to accomplish this. #!/usr/bin/env python data = {} lrgColumn = 0 for line in open("test.txt","r").read().splitlines(): char = line[0].lower() if not char in data: data[char] = [line] else: data[char].append(line) for item in data: print item.ljust(10), if len(data[item]) > lrgColumn: lrgColumn = len(data[item]) print for item in range(lrgColumn): for i in data.iteritems(): try: print i[1][item].ljust(10), except IndexError: print "".ljust(10), print

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[OT] Py3k news
by Kent Johnson Aug. 31, 2007

Aug. 31, 2007

I don't usually post general announcements and news items here but we did recently have a discussion about whether Python 3000 is real or fictional. It's very real... Last week over twenty developers came together for a successful Py3k sprint. As a result the first alpha release is expected in 'a few days'. http://google-code-updates.blogspot.com/2007/08/updates-from-latest-python-… Kent

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