🌐 Mailman 3 March 2005 - Python-list - python.org

File Uploads
by Doug Helm April 1, 2005

April 1, 2005

Hey, Folks: I'm trying to write a very simple file upload CGI. I'm on a Windows server. I *am* using the -u switch to start Python for CGIs, as follows: c:\python\python.exe -u %s %s I *do* have write permissions on the directory I'm trying to write to. But, when I click submit, it just hangs. Any help would be greatly appreciated. Thanks. Here's the code... Upload.py import cgi print "content-type: text/html\n\n" form = cgi.FieldStorage() if not form: print """ <html> <head></head> <body> <form name="frmMain" action="Upload.py" method="POST" enctype="multipart/form-data"> <input type="file" name="filename"><br> <input type="submit"> </form> </body> </html> """ else: import BLOB lobjUp = BLOB.BLOB() if lobjUp.Save('filename', 'SomeFile.jpg'): print """ <html> <head></head> <body> File successfully saved. </body> </html> """ else: print """ <html> <head></head> <body> Unable to save file. </body> </html> """ -------------- Blob.py import cgi import staticobject cTrue = 1 cFalse = 0 try: import msvcrt,os msvcrt.setmode( 0, os.O_BINARY ) # stdin = 0 msvcrt.setmode( 1, os.O_BINARY ) # stdout = 1 except ImportError: pass class BLOB(staticobject.StaticObject): def __init__(self): self.initializing = cTrue staticobject.StaticObject.__init__(self) self.initializing = cFalse def Save(self, pstrFormFieldName, pstrFilePathAndName): # tried this first -- same result -- just hangs... # try: # form = cgi.FieldStorage() # item = form[pstrFormFieldName] # if item.file: # data = item.file.read() # f = open(pstrFilePathAndName,'wb') # f.write(data) # f.close() # return cTrue # else: # return cFalse # except: # return cFalse form = cgi.FieldStorage() f = open(pstrFilePathAndName,'wb') f.write(form[pstrFormFieldName].value) f.close()

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Printing Varable Names Tool.. Feedback requested.
by Ron_Adam April 1, 2005

April 1, 2005

Hi, Sometimes it just helps to see what's going on, so I've been trying to write a tool to examine what names are pointing to what objects in the current scope. This still has some glitches, like not working in winpython or the command line, I get a 'stack not deep enough' error. I haven't tested it on linux yet either. It could be something with my python install.(?) Anyway, here's the source with an example output. I'm still not sure what to call it. Pnames stands for printnames, but if you think of something better let me know. Some things I think will be good is shortening long output such as lists and dictionaries to '[...]' or '[:] or a few chars at the beginning and end with '...' in the middle. I think it's important to keep the output short and readable. Any suggestions would be apreciated. :) Ron IDLE 1.1.1c1 ==== No Subprocess ==== >>> [globals] __builtins__ --> <module> __doc__ --> <docstring> __file__ --> C:\Python24\Lib\idlelib\idle.pyw __main__ --> <module> __name__ --> __main__ g --> 45 glist --> ['a changed', 'list'] <-- test2:a h --> 45 idlelib --> <module> pnames --> <function> sys --> <module> test1 --> <function> test2 --> <function> test2.at1 --> [True] <-- test2:aaa [test1] t --> ['altered'] <-- test2:w [locals:test2] a --> ['a changed', 'list'] <-- globals:glist aaa --> [True] <-- globals:test2.at1 w --> ['altered'] <-- test1:t Paused >>> #---start--- # pnames.py """ A utility to print the value of variables for debugging purposes. To use: import prnames and insert prnames.prnames() in the program where you want to examin names. Pressing any key will continue. Author: Ronald Adam """ import sys if __name__ is not '__main__': import __main__ def pnames(): """ View """ objdict = {} # Collect references to object. namelist = [] # List of names and values by frame. n = 1 name = None while name!= 'runcode': # Move up in the frames to gather name data. # until the application global frame is reached. name = sys._getframe(n).f_code.co_name if name != 'runcode': # This keeps it out of idle's name space. namelst = [name,[]] namespace = sys._getframe(n).f_locals keys = namespace.keys() # Get all the names in this frame. for k in keys: try: trash = objdict[id(namespace[k])][name] except: try: objdict[id(namespace[k])][name]=[k] except: objdict[id(namespace[k])]={name:[k]} else: objdict[id(namespace[k])][name].append(k) namelst[1].append((k,namespace[k],id(namespace[k]))) #namelist.append(namelst) #try: attribs = None try: attribs = namespace[k].func_dict except: pass if attribs: for att in attribs: attname = k+'.'+att try: trash = objdict[id(attribs[att])][attname] except: try: objdict[id(attribs[att])][name]=[attname] except: objdict[id(attribs[att])]={name:[attname]} else: objdict[id(attribs[att])][name].append(attname) namelst[1].append((attname,attribs[att],id(attribs[att]))) namelist.append(namelst) n += 1 # Now print what we collected. namelist.reverse() # Reverse it so we have globals at the top. tab = 0 for gname, group in namelist: # Sort it. def sortnocase(stringlist): tupleList = [(x[0].lower(), x) for x in stringlist] tupleList.sort() return [x[1] for x in tupleList] group = sortnocase(group) if gname == chr(63): # Idle uses this as name as app-globals. gname = 'globals' if gname == namelist[-1:][0][0]: gname = 'locals:'+gname # Indicate locals group. print '%s[%s]'%(' '*tab, gname) tab += 1 for name, obj, objid in group: # Print the varable name print ' '*tab,name,'-->', # Remove & replace a lot of clutter as we print it. # List other names pointing to mutable objects. if name == '__doc__': obj = '<docstring>' if 'module' in str(obj): # These remove clutter obj = '<module>' # More probably needs to be if 'function' in str(obj): # done here. obj = '<function>' # Print the object print obj, # Print the other names pointing to # the object. obj2 = '' if type(obj) not in [int, str, float, bool, tuple] \ and obj not in [True, False, None]: for obj in objdict[objid].keys(): name2 = objdict[objid][obj] n = 0 if len(name2): for name3 in name2: if obj == chr(63): obj = 'globals' if name3 != name: if n>0: obj2 += ', ' if obj != gname: obj2 += obj+':'+name3 else: obj2 += name3 n += 1 if len(obj2)>0: obj2 = '<-- '+obj2 print obj2 raw_input( 'Paused') def test1(): global g t = g t = [9] test2.at1 = [True] test2(t) def test2(w): a = glist aaa = test2.at1 test2.at1[0] = True a[0] = 'a changed' w[0] = 'altered' pnames() if __name__ == '__main__': # Make a few globals to see. g = 45 h = g glist = ['just a','list'] # Put an attribute on a function # to find. test2.at1 = 25 # Run test function. test1() #---end---

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Re: property and virtuality
by Steven Bethard April 1, 2005

April 1, 2005

Laszlo Zsolt Nagy wrote: > > My problem is about properties and the virtuality of the methods. I > would like to create a property whose get and set methods > are virtual. Perhaps you want to roll your own VirtualProperty descriptor? Here's one based off the property implementation in Raymond Hettinger's How-To Guide for Descriptors[1]: py> class VirtualProperty(object): ... def __init__(self, getname=None, setname=None, delname=None, ... doc=None): ... self.getname = getname ... self.setname = setname ... self.delname = delname ... self.__doc__ = doc ... def __get__(self, obj, type=None): ... if obj is None: ... return self ... if self.getname is None: ... raise AttributeError('unreadable attribute') ... try: ... fget = getattr(obj, self.getname) ... except AttributeError: ... raise TypeError('%s object does not have a %s method' % ... (type(obj).__name__, self.getname)) ... return fget() ... def __set__(self, obj, value): ... if self.setname is None: ... raise AttributeError("can't set attribute") ... try: ... fset = getattr(obj, self.setname) ... except AttributeError: ... raise TypeError('%s object does not have a %s method' % ... (type(obj).__name__, self.setname)) ... fset(value) ... def __delete__(self, obj): ... if self.delname is None: ... raise AttributeError("can't delete attribute") ... try: ... fdel = getattr(obj, self.delname) ... except AttributeError: ... raise TypeError('%s object does not have a %s method' % ... (type(obj).__name__, self.delname)) ... fdel() ... py> class C(object): ... def getx(self): ... return 'C' ... x = VirtualProperty('getx', 'setx', 'delx') ... py> class D(C): ... def getx(self): ... try: ... return self._x ... except AttributeError: ... return 'D' ... def setx(self, x): ... self._x = x ... py> c = C() py> c.x 'C' py> c.x = 1 Traceback (most recent call last): File "<interactive input>", line 1, in ? File "<interactive input>", line 24, in __set__ TypeError: C object does not have a setx method py> del c.x Traceback (most recent call last): File "<interactive input>", line 1, in ? File "<interactive input>", line 33, in __delete__ TypeError: C object does not have a delx method py> d = D() py> d.x 'D' py> d.x = 1 py> d.x 1 py> del d.x Traceback (most recent call last): File "<interactive input>", line 1, in ? File "<interactive input>", line 33, in __delete__ TypeError: D object does not have a delx method STeVe [1] http://users.rcn.com/python/download/Descriptor.htm

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Re: Controling the ALU
by Grant Edwards April 1, 2005

April 1, 2005

On 2005-03-31, Cesar Andres Roldan Garcia <cesar.andres(a)gmail.com> wrote: > How can I control an ALU from a PC using Python? The ALU is buried pretty deep in the CPU. The ALU is part of what is actually executing the instructions that _are_ Python. -- Grant Edwards grante Yow! VICARIOUSLY at experience some reason visi.com to LIVE!!

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Newbie Shell Editor Question
by Kash March 31, 2005

March 31, 2005

Hi Everyone, I am new to python. I have just installed it. I am went to the python website and used it to download python and a beginners tutorial. I set the environment variables as explained in the faq. However when I start idle and run a program from it; I get the following types of errors; however I can run the same programs no problem from my command prompt. Can anyone please tell me what I am doing wrong? I thought Idle was used to test programs in. I am able to open a new window and write code, save it and then run that code; but just not if I type it into the main idle window directly. Any help would greatly appreciated, thank you. Kash This is my error: ---------------------------- IDLE 1.1 >>> python hello.py SyntaxError: invalid syntax >>> python hello SyntaxError: invalid syntax >>> exit 'Use File/Exit or your end-of-file key to quit IDLE' >>> print "Hello" Hello >>> hello Traceback (most recent call last): File "<pyshell#4>", line 1, in -toplevel- hello NameError: name 'hello' is not defined >>> hello.py Traceback (most recent call last): File "<pyshell#5>", line 1, in -toplevel- hello.py NameError: name 'hello' is not defined >>>

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assignments - want a PEP
by Kay Schluehr March 31, 2005

March 31, 2005

>From time to time I still use my old Mathematica system. The Mathematica language has some nice properties. The one I like best is the possibility to create symbols from nothing. Translated into the Python realm following creations are possible: >>> a a That's it. Just make an 'a' as a pure symbol. The reason for those symbols is late evaluation. Most of the time an expression should be transformed and simplified before it is finally evaluated using concrete numbers or other stuff. I tried to mimic this in Python using a Symbol() class: >>> a = Symbol() >>> a a So 'a' would be a Symbol object that is represented by the name "a" not by the standard format information that tells us that a is some member of class Symbol(). Starting with Symbol() subclsses of Symbol() e.g Expr() could overload operators like __add__, __mul__ etc. in order to create new symbolic objects: >>> a,b = Expr(),Expr() >>> (a+b)/c a+b --- c The availability of Symbol() would make it easy to create a Computer Algebra System ( CAS ) in Python, just using standard Python operators. Unfortunately it is not possible to implement Symbol() in an elegant way. Symbol() has to retrieve somehow it's own name from the environment where the name is created, but no assignment/name binding event is accessible to Python objects. I want to propose making name binding accessible by introducing an __assign__ method which is called, whenever an object is bound to a name. By default the __assign__ method does nothing at all but can be implemented by custom classes. def __assign__(self,own_name): # do somtehing with me and my name Instead of changing the behaviour of the current assignment operator "=" one could think about introduction of a new assignment ":=" that is connected to the __assign__ method of custom classes if available. What do You think? Regards, Kay

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Re: split an iteration
by Raymond Hettinger March 31, 2005

March 31, 2005

[Robin Becker] > This function from texlib in oedipus.sf.net is a real cpu hog and I determined > to see if it could be optimized. > > def add_active_node(self, active_nodes, node): > """Add a node to the active node list. > The node is added so that the list of active nodes is always > sorted by line number, and so that the set of (position, line, > fitness_class) tuples has no repeated values. > """ If you can change the data structure to be an actual list of tuples, then the bisect module can be used directly: insert_index = bisect.bisect_left(active_nodes, node) if active_nodes[insert_index] == node: return # avoid creating a duplicate entry active_nodes.insert(insert_index, node) If the data structure cannot be changed to tuples, then try adding a custom compare operation to the node class: def __cmp__(self, other): return cmp((self.line, self.position, self.fitness_class), (other.line, other.position, other.fitness_class)) > insert_index = nan > for index, a in enumerate(active_nodes): > if a.line>=node_line: > insert_index = index > break > index = insert_index This loop can be squeezed a bit more using itertools.imap() and operator.attrgetter() for the attribute lookup: for index, aline in enumerate(imap(attrgetter('line'), active_nodes): if aline > node_line: . . . > Is there a fast way to get enumerate to operate over a slice of an iterable? enumerate(s) is the same as izip(count(), s). So, to start from position i, write: for index, value in izip(count(i), s[i:]): . . . That being said, your best bet is to eliminate the initial linear search which is likely consuming most of the clock cycles. Also, I noticed that the code does not reference self. Accordingly, it is a good candidate for being a staticmethod or standalone function. Raymond Hettinger

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Numarray newbie question
by ChinStrap March 31, 2005

March 31, 2005

I know there are probably alternatives for this with the standard library, but I think that would kill the speed I get with numarray: Say I have two 2-dimensional numarrays (x_mat and y_mat, say), and a function f(x,y) that I would like to evaluate at every index. Basically I want to be able to say f(x_mat,y_mat) and have it return a numarray with the same shape and element wise evaluation of f. I know, I want a ufunc, but they look scary to write my own. Are there any functions that do this? Or is writing ufuncs easier than it seems? Thanks, -Chris Neff

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(no subject)
by None March 31, 2005

March 31, 2005

#! rnews 1765 Newsgroups: comp.lang.python Path: news.xs4all.nl!newsspool.news.xs4all.nl!transit.news.xs4all.nl!195.241.76.212.MISMATCH!transit1.news.tiscali.nl!tiscali!transit0.news.tiscali.nl!tudelft.nl!130.161.131.117.MISMATCH!tudelft.nl!newsfeed.multikabel.nl!gatel-ffm!gatel-ffm!proxad.net!proxad.net!newsread.com!news-xfer.newsread.com!nntp.abs.net!attws2!ip.att.net!NetNews1!xyzzy!nntp From: Harry George <harry.g.george(a)boeing.com> Subject: Re: Generating RTF with Python X-Nntp-Posting-Host: cola2.ca.boeing.com Content-Type: text/plain; charset=us-ascii Message-ID: <xqxd5tfo7p1.fsf(a)cola2.ca.boeing.com> User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 Lines: 37 Sender: hgg9140(a)cola2.ca.boeing.com Organization: The Boeing Company References: <mailman.1137.1112277702.1799.python-list(a)python.org> <slrnd4o7hd.h5k.axel(a)m2.sine> Mime-Version: 1.0 Date: Thu, 31 Mar 2005 20:56:42 GMT Xref: news.xs4all.nl comp.lang.python:370154 Axel Straschil <axel(a)straschil.com> writes: > Hello! > > > does anyone know of a high-level solution to produce RTF from Python=20 > > (something similar to > > Reportlab for producing PDF)? > > Spend hours of googeling and searching, also in this NG, about two > months ago. My conclusion is: On windwos, maybe you can include some > hacks with dll's, under linux, linux support for generating rtf is none, > and so is python's. > > My workaround was: > http://www.research.att.com/sw/download/ > This includes an html2rtf converter, which I access from python via > popen and temporary files. Not high-level, not very sexy ... ;-( > > Lg, > AXEL. > -- > "Aber naja, ich bin eher der Forentyp." Wolfibolfi's outing in > http://www.informatik-forum.at/showpost.php?p=206342&postcount=10 I generate docbook and convert that to rtf. I generate the docbook from my pdx markup: http://www.seanet.com/~hgg9140/comp/index.html#L007 If you go this route, your python code is actually writing pdx, and you need a 2 step conversion (pdx2docbook.py, then openjade for the xml-to-rtf step). -- harry.g.george(a)boeing.com 6-6M21 BCA CompArch Design Engineering Phone: (425) 294-4718

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(no subject)
by None March 31, 2005

March 31, 2005

#! rnews 1765 Newsgroups: comp.lang.python Path: news.xs4all.nl!newsspool.news.xs4all.nl!transit.news.xs4all.nl!195.241.76.212.MISMATCH!transit1.news.tiscali.nl!tiscali!transit0.news.tiscali.nl!tudelft.nl!130.161.131.117.MISMATCH!tudelft.nl!newsfeed.multikabel.nl!gatel-ffm!gatel-ffm!proxad.net!proxad.net!newsread.com!news-xfer.newsread.com!nntp.abs.net!attws2!ip.att.net!NetNews1!xyzzy!nntp From: Harry George <harry.g.george(a)boeing.com> Subject: Re: Generating RTF with Python X-Nntp-Posting-Host: cola2.ca.boeing.com Content-Type: text/plain; charset=us-ascii Message-ID: <xqxd5tfo7p1.fsf(a)cola2.ca.boeing.com> User-Agent: Gnus/5.09 (Gnus v5.9.0) Emacs/21.3 Lines: 37 Sender: hgg9140(a)cola2.ca.boeing.com Organization: The Boeing Company References: <mailman.1137.1112277702.1799.python-list(a)python.org> <slrnd4o7hd.h5k.axel(a)m2.sine> Mime-Version: 1.0 Date: Thu, 31 Mar 2005 20:56:42 GMT Xref: news.xs4all.nl comp.lang.python:370154 Axel Straschil <axel(a)straschil.com> writes: > Hello! > > > does anyone know of a high-level solution to produce RTF from Python=20 > > (something similar to > > Reportlab for producing PDF)? > > Spend hours of googeling and searching, also in this NG, about two > months ago. My conclusion is: On windwos, maybe you can include some > hacks with dll's, under linux, linux support for generating rtf is none, > and so is python's. > > My workaround was: > http://www.research.att.com/sw/download/ > This includes an html2rtf converter, which I access from python via > popen and temporary files. Not high-level, not very sexy ... ;-( > > Lg, > AXEL. > -- > "Aber naja, ich bin eher der Forentyp." Wolfibolfi's outing in > http://www.informatik-forum.at/showpost.php?p=206342&postcount=10 I generate docbook and convert that to rtf. I generate the docbook from my pdx markup: http://www.seanet.com/~hgg9140/comp/index.html#L007 If you go this route, your python code is actually writing pdx, and you need a 2 step conversion (pdx2docbook.py, then openjade for the xml-to-rtf step). -- harry.g.george(a)boeing.com 6-6M21 BCA CompArch Design Engineering Phone: (425) 294-4718

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