Why does list.index throws an exception instead of returning a value like say -1? What's the idea behind this? To me it looks cleaner to deal with special values, etc than exceptions. EDIT: I didn't realize -1 to be usable, but in that case, how about a value of None? ...
I'm just trying to streamline one of my classes and have introduced some functionality in the same style as the flyweight design pattern. However, I'm a bit confused as to why __init__ is always called after __new__. I wasn't expecting this. Can anyone tell me why this is happening and how I implement this functionality otherwise? (apar...
Hello all! I'm trying to wrap the Patricia Tries (Perl's NET::Patricia) to be exposed in python. I am having difficulty with one of the classes. So instances the patricia node (below) as viewed from python have a "data" property. Reading it goes fine, but writing to it breaks. typedef struct _patricia_node_t { u_int bit; /* ...
I've got a dictionary like: { 'a': 6, 'b': 1, 'c': 2 } I'd like to iterate over it by value, not by key. In other words: (b, 1) (c, 2) (a, 6) What's the most straightforward way? ...
If I have a dictionary like: { 'a': 1, 'b': 2, 'c': 3 } How can I convert it to this? [ ('a', 1), ('b', 2), ('c', 3) ] And how can I convert it to this? [ (1, 'a'), (2, 'b'), (3, 'c') ] ...
Alright, so I was taking a look at some source when I came across this: >>> def __parse(self, filename): ... "parse ID3v1.0 tags from MP3 file" ... self.clear() ... try: ... fsock = open(filename, "rb", 0) ... try: ... fsock.seek(-128, 2) ... tagdata = fsock...
I have a list full of various bits of information that I would like to pass to several strings for inclusion via the new string format method. As a toy example, let us define thelist = ['a', 'b', 'c'] I would like to do a print statement like print '{0} {2}'.format(thelist) and print '{1} {2}'.format(thelist) When I run this, I rece...
I want to benchmark PHP vs Pylons. I want my comparison of both to be as even as possible, so here is what I came up with: PHP 5.1.6 with APC, using a smarty template connecting to a MySQL database Python 2.6.1, using Pylons with a mako template connecting the the same MySQL database Is there anything that I should change in that set...
I am trying to find some examples but no luck. Anyone knows some examples on the net? I want to know what it returns when it can't find, and how to specify from start to end, which I guess is gonna be 0, -1. ...
Im considering doing a small project as a part of my masters for doing ocr just for sheetmusic instead of text. I think PIL and Python would be fine for simple proof of concept O"notes"R. My question is: Has anyone got any "dont do it with PIL use xyz instead" or something in that alley? EDIT: My delicius links regarding the subject i...
I have a HTTP client in Python which needs to use TLS. I need not only to make encrypted connections but also to retrieve info from the remote machine, such as the certificate issuer. I need to make connection to many HTTP servers, often badly behaved, so I absolutely need to have a timeout. With non-TLS connections, mysocket.settimeout(...
Is there a common function to do this? Right now I'm just doing the following (and overriding __len__) idx < 0: idx = len(self) + idx if idx < 0 or idx >= len(self): raise IndexError, "array index (%d) out of range [0, %d)" %(idx, len(self)) ...
During a bout of C# and WPF recently, I got to like C#'s properties: public double length_inches { get { return length_metres * 39.0; } set { length_metres = value/39.0; } } Noticing, of course, that length_metres may change from being a field to a property, and the code need not care. WPF can also bind UI elements to object p...
Several months ago, I wrote a blog post detailing how to achieve tab-completion in the standard Python interactive interpreter--a feature I once thought only available in IPython. I've found it tremendously handy given that I sometimes have to switch to the standard interpreter due to IPython unicode issues. Recently I've done some work...
Is there any mechanism to comment out large blocks of Python code? Right now the only ways I can see of commenting out code are to either start every line with a #, or to enclose the code in """ (triple quotes), except that actually makes it show up in various doc tools. Edit--After reading the answers (and referring to the "duplicate")...
[resolved] I tweaked the preferences in komodo edit and ended up with: don't auto indent don't allow file contents to override tab settings prefer tab characters over spaces 4 spaces per indent 4 width of each tab char I also set komodo to show whitespace and tabs, which eneded up revealing the screwed up sections. yeah - it's a ...
I'd like to create a graphic image on the fly based on user input, and then present that image as a PNG file (or jpg or gif if necessary, but PNG is preferred). This is actually for an astrology application; what I'd like to do is generate the chart in PNG for display. Python or Ruby is fine; in fact, the library available may determin...
Can someone please show me a full python sample code that uses pyserial, i have the package and am wondering how to send the AT commands and read them back! H-e-l-p ! ...
A equation takes values in the following form : x = [0x02,0x00] # which is later internally converted to in the called function to 0x300 y = [0x01, 0xFF] z = [0x01, 0x0F] How do I generate a series of test values for this function ? for instance I want to send a 100 odd values from a for loop for i in range(0,300): ...
Hi, I want to learn a text manipulation language and I have zeroed in on Python. Apart from text manipulation Python is also used for numerical applications, machine learning, AI, etc. My question is how do I approach the learning of Python language so that I am quickly able to write sophisticated text manipulation utilities. Apart from...