🌐 Mailman 3 June 2008 - 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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cx_Oracle help
by Greg Lindstrom Jan. 6, 2011

Jan. 6, 2011

Hello, I'm trying to help out a friend and am stumped. Can you help me out? Thanks, --greg - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - I will briefly explain the problem I am facing. I am using Oracle 9.2, Python 2.5 and I installed cx_Oracle- 4.3.1-win32-9i-py25 in Python. From python I tried following : >>> import cx_Oracle >>> myDsn = cx_Oracle.makedsn('ISCN47',1521,'AUBDBS01') >>> CONN = cx_Oracle.connect(myusr, mypwd, myDsn) Traceback (most recent call last): File "<pyshell#4>", line 1, in <module> conn = cx_Oracle.Connection('scott','tiger',myDsn) RuntimeError: Unable to acquire Oracle environment handle I have set the below environment variables too NLS_LANG: <snip>.WE8MSWIN1252 ORACLE_HOME: D:\Tools\oracle\ora92 ORACLE_SID: AUBDBS01 PYTHON_HOME: d:\Utility\Python25 PYTHONPATH: %PYTHON_HOME%\lib;%PYTHON_HOME%\DLLs;%PYTHON_HOME%\Lib\site-packages;%ORACLE_HOME%\bin LD_LIBRARY_PATH: %LD_LIBRARY_PATH%;D:\Tools\oracle\ora92\lib Not getting any idea where I am wrong? Regards, Kishore

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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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Learning Python
by Fred P Dec. 13, 2009

Dec. 13, 2009

Hey Everyone, I am completely new at python, but not new to programming or scripting. I have a couple of years of LUA scripting experience, about a year of C++ classes, and used to be very efficient at c-shell scripting in unix. My question for you guys: 1) How do I get Started? 2) Recommend any specific Books? 3) Any online tutors/ forums that would benefit a newbie 4) Any online classes that teach python? I have taken online c++ courses, and found them helpful. I was hoping to find something for python. My main objective is to write scripts for the following type of applications File management, file copies/syncs/ compares Text manipulation - like parsing text files to replace or augment specific values Integration into current applications to write redundant routines and maybe some day plugins I am not even sure what else, but I do know that every time i think of something that we need at work, other people say, "That would be a good task for a python script" and I would eventually like to be able to do something about that. Thanks Fred

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Re: [Tutor] Hands-on beginner's project?
by George Oliver Oct. 3, 2008

Oct. 3, 2008

> Python Universe Builder (PUB) is an Interactive Fiction module for > Python. It provides a > programming environment similar to that of Inform or TADS but runs > under any Python > interpreter. > > http://py-universe.sourceforge.net/ There also is PAWS (Python adventure writing system): http://home.fuse.net/wolfonenet/PAWS.htm Just for reference, other slightly more complicated examples of separating the game logic and data can be found in the mud genre. I recently wrote up a list of all the Python mud frameworks I could find: http://www.mudconnect.com/discuss/discuss.cgi?mode=MSG&area=coders&message=…

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addressbook program
by Danny Laya July 3, 2008

July 3, 2008

Hi I am making an addressBook program now, and you know some problem, the program doesn't work. This is the code : # Loading the addressbook filename = "addbook.dat" def readBook(book) import os if os.path.exists(filename): store = open(filename,'r') for line in store: name = line.rstrip() entry = store.next().rstrip() book[name] = entry store.close() # Saving the address book def saveBook(book): store = open(filename,"w") for name,entry in book.items(): store.write(name + '\n') store.write(entry + '\n') store.close() # Getting User Input def getChoice(menu): print menu choice = int(raw_input("Select a choice(1-4): ")) return choice # Adding an entry def addEntry(book): name = raw_input("Enter a name: ") entry = raw_input("Enter a street, town and phone number: ") book[name] = entry # Removing an entry def removeEntry(book): name = raw_input("Enter a name: ") del(book[name]) #Finding an Entry def findEntry(book): name = raw_input("Enter a name: ") if name in book: print name, book[name] else: print "Sorry, no entry for: ", name # Quitting the program def main(): theMenu = ''' 1) Add Entry 2) Remove Entry 3) Find Entry 4) Quit and save ''' theBook = {} readBook(theBook) choice = getChoice(theMenu) while choice != 4: if choice == 1: addentry(theBook) elif choice == 2: removeEntry(theBook) elif choice == 3: findEntry(theBook) else: print "Invalid choice, try again" choice = getChoice(theMenu) saveBook(theBook) # Call the main function if __name__ == "__main__": main() Help me guy's .... Some enlightenment and explanation about the wrong and how this program works maybe ...... I got this code from Alan Gauld tutorial in Handling Files part.

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list objects are unhashable
by Norman Khine July 1, 2008

July 1, 2008

Hello, I would like to count list items but am not 100% sure how to do it. Here is what I have so far: for brain in brains: x = getattr(brain, horizontal) y = getattr(brain, vertical) if x and y and (x, y) in table: table[(x, y)] += 1 table[(x, '')] += 1 table[('', y)] += 1 table[('', '')] += 1 but when I run this, I get the following error on the line: if x and y and (x, y) in table: TypeError: list objects are unhashable where: x = ['airlines-scheduled', 'airport-car-parking'] I am basically looping through files within each file, I have an entity, for example: file1 <topic>airlines-scheduled airport-car-parking</topic> file2 <topic>airport-car-parking</topic> etc... So the above code counts all occurrences of 'airport-car-parking' and sums it up. All works well if, I change the code to: for brain in brains: x = getattr(brain, horizontal) x = string.join(x, '' ) y = getattr(brain, vertical) y = string.join(y, '' ) if x and y and (x, y) in table: table[(x, y)] += 1 table[(x, '')] += 1 table[('', y)] += 1 table[('', '')] += 1 So now my list becomes a string, which is not really good for me, as this fails when there is more then one item. Is there a better way to loop through this and sum up all occurrences of each entry ie 'airport-car-parking' Cheers Norman

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Re: [Tutor] Deleting specified files using a python program...help with code?]
by David July 1, 2008

July 1, 2008

I am learning python from books and this mailing list. I used the suggestions to come up with this; #!/usr/bin/python # Filename : new_remove-file.py import os import sys import glob dir_input = raw_input('Enter dir: ') win_trace = ['*.ini', '*.db'] files_removed = 0 for root, dirs, files in os.walk(dir_input): for trace in win_trace: win_trace_path = os.path.join(root, trace) for filename in glob.glob(win_trace_path): if os.path.exists(filename): print filename else: print 'No files found' confirmation = raw_input('Confirm removal: ') if confirmation == 'y': print "removing '%s'" % filename os.remove(filename) files_removed += 1 elif confirmation == 'n': pass else: sys.exit() if files_removed : print '%d files removed' % files_removed else : print 'No files found' Here is the output; david@opteron ~ $ ./new_remove_file.py Enter dir: test test/test.ini test/test.db Confirm removal: y removing 'test/test.db' 1 files removed Please point me in the direction as to why only one file is removed. thanks -david -- Powered by Gentoo GNU/LINUX http://www.linuxcrazy.com

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Deleting specified files using a python program...help with code?
by Saad Javed July 1, 2008

July 1, 2008

I transfer files a lot between my windows and linux partitions...these folders sometimes contain *.db and *.ini files which are not recognized or used by linux. So i tried to write a program to crawl through my home dir and remove these files...I'm *very* new to programming and python so please be gentle. Here is the code: *import os list = ['*.ini', '*.db'] for root, dirs, files in os.walk('/home/saad'): **for list in files: **os.remove(os.path.join('root', 'list')) print 'done'* Unfortunately its a bit too efficient and nearly wiped my home dir before i manually killed it. Again...treat me like a super noob. Saad

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Re: [Tutor] Is "var = None" in Python equivalent to "Set var
by Tony Cappellini June 30, 2008

June 30, 2008

Message: 5 Date: Mon, 30 Jun 2008 11:49:59 +0200 From: "Andre Engels" <andreengels(a)gmail.com> Subject: Re: [Tutor] Is "var = None" in Python equivalent to "Set var = Nothing"in VB? To: Kelie <kf9150(a)gmail.com> Cc: tutor(a)python.org Message-ID: <6faf39c90806300249k493e233o9d72fff3841e0c29(a)mail.gmail.com> Content-Type: text/plain; charset=UTF-8 >>I don't know about Visual Basic, In VB6 ( I have not worked with VB.NET), objects are set to Nothing when they go out of scope, yet there is a fair amount lot of code out there where objects are explicitly set to Nothing. This is a pretty common practice in VB land. >>but in Python these statements are unnecessary. What happened to "Explicit is better than implicit"?

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