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  • python: can't terminate a thread hung in socket.recvfrom() call

    - by Dihlofos
    Hello, everyone I cannot get a way to terminate a thread that is hung in a socket.recvfrom() call. For example, ctrl+c that should trigger KeyboardInterrupt exception can't be caught. Here is a script I've used for testing: from socket import * from threading import Thread from sys import exit class TestThread(Thread): def __init__(self,host="localhost",port=9999): self.sock = socket(AF_INET,SOCK_DGRAM) self.sock.bind((host,port)) super(TestThread,self).__init__() def run(self): while True: try: recv_data,addr = self.sock.recvfrom(1024) except (KeyboardInterrupt, SystemExit): sys.exit() if __name__ == "__main__": server_thread = TestThread() server_thread.start() while True: pass The main thread (the one that executes infinite loop) exits. However the thread that I explicitly create, keeps hanging in recvfrom(). Please, help me resolve this.

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  • Unpacking tuple types in Scala

    - by jpalecek
    I was just wondering, can I decompose a tuple type into its components' types in Scala? I mean, something like this trait Container { type Element } trait AssociativeContainer extends Container { type Element <: (Unit, Unit) def get(x : Element#First) : Element#Second }

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  • Validating age field

    - by Marcelo
    Hi people, I'm trying to validate an age field in a form but I'm having some problem. First I tried to make sure that the field will not be send empty. I don't know JavaScript so I searched some scripts and adapted them to this: function isInteger (s) { var i; if (isEmpty(s)) if (isInteger.arguments.length == 1) return 0; else return (isInteger.arguments[1] == true); for (i = 0; i < s.length; i++) { var c = s.charAt(i); if (!isDigit(c)) return false; } return true; } function isEmpty(s) { return ((s == null) || (s.length == 0)) } function validate_required(field,alerttxt) { with (field) { if (value==null||value=="") { alert(alerttxt);return false; } else { return true; } } } function validate_form(thisform) { with (thisform) { if ((validate_required(age,"Age must be filled out!")==false) || isInteger(age,"Age must be and int number")==false)) {email.focus();return false;} } } //html part <form action="doador.php" onsubmit="return validate_form(this)" method="post"> It's working fine for empty fields, but if I type any letters or characters in age field, it'll be sent and saved a 0 in my database. Can anyone help me? Sorry for any mistake in English, and thanks in anvance for your help.

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  • Recursive query question - break rows into columns?

    - by Stew
    I have a table "Families", like so FamilyID PersonID Relationship ----------------------------------------------- F001 P001 Son F001 P002 Daughter F001 P003 Father F001 P004 Mother F002 P005 Daughter F002 P006 Mother F003 P007 Son F003 P008 Mother and I need output like FamilyID PersonID Father Mother ------------------------------------------------- F001 P001 P003 P004 F001 P002 P003 P004 F001 P003 F001 P004 F002 P005 P006 F002 P006 F003 P007 P008 F003 P008 In which the PersonID of the Father and Mother for a given PersonID are listed (if applicable) in separate columns. I know this must be a relatively trivial query to write (and therefore to find instructions for), but I can't seem to come up with the right search terms. Searching "SQL recursive queries" has gotten me closest, but I can't quite translate those methods to what I'm trying to do here. I'm trying to learn, so multiple methods are welcome, as is vocabulary I should read up on. Thanks!

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  • Python doesn't work properly when I execute a script after using Right Click >> Command Prompt Here

    - by Dominic Bou-Samra
    This is a weird bug. I know it's something funky going on with my PATH variable, but no idea how to fix it. If I have a script C:\Test\test.py and I execute it from within IDLE, it works fine. If I open up Command Prompt using Runcmd.exe and navigate manually it works fine. But if I use Windows 7's convenient Right Click on folder Command Prompt Here then type test.py it fails with import errors. I also cannot just type "python" to reach a python shell session if I use the latter method above. Any ideas?

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  • How do I get user input to refer to a variable in Python?

    - by somefreakingguy
    I would like to get user input to refer to some list in my code. I think it's called namespace? So, what would I have to do to this code for me to print whatever the user inputs, supposing they input 'list1' or 'list2'? list1 = ['cat', 'dog', 'juice'] list2 = ['skunk', 'bats', 'pogo stick'] x = raw_input('which list would you like me to print?') I plan to have many such lists, so a series of if...then statements seems unruly.

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  • Haskell Ord instance with a Set

    - by mvid
    I have some code that I would like to use to append an edge to a Node data structure: import Data.Set (Set) import qualified Data.Set as Set data Node = Vertex String (Set Node) deriving Show addEdge :: Node -> Node -> Node addEdge (Vertex name neighbors) destination | Set.null neighbors = Vertex name (Set.singleton destination) | otherwise = Vertex name (Set.insert destination neighbors) However when I try to compile I get this error: No instance for (Ord Node) arising from a use of `Set.insert' As far as I can tell, Set.insert expects nothing but a value and a set to insert it into. What is this Ord?

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  • Coding the Python way

    - by Aaron Moodie
    I've just spent the last half semester at Uni learning python. I've really enjoyed it, and was hoping for a few tips on how to write more 'pythonic' code. This is the __init__ class from a recent assignment I did. At the time I wrote it, I was trying to work out how I could re-write this using lambdas, or in a neater, more efficient way, but ran out of time. def __init__(self, dir): def _read_files(_, dir, files): for file in files: if file == "classes.txt": class_list = readtable(dir+"/"+file) for item in class_list: Enrol.class_info_dict[item[0]] = item[1:] if item[1] in Enrol.classes_dict: Enrol.classes_dict[item[1]].append(item[0]) else: Enrol.classes_dict[item[1]] = [item[0]] elif file == "subjects.txt": subject_list = readtable(dir+"/"+file) for item in subject_list: Enrol.subjects_dict[item[0]] = item[1] elif file == "venues.txt": venue_list = readtable(dir+"/"+file) for item in venue_list: Enrol.venues_dict[item[0]] = item[1:] elif file.endswith('.roll'): roll_list = readlines(dir+"/"+file) file = os.path.splitext(file)[0] Enrol.class_roll_dict[file] = roll_list for item in roll_list: if item in Enrol.enrolled_dict: Enrol.enrolled_dict[item].append(file) else: Enrol.enrolled_dict[item] = [file] try: os.path.walk(dir, _read_files, None) except: print "There was a problem reading the directory" As you can see, it's a little bulky. If anyone has the time or inclination, I'd really appreciate a few tips on some python best-practices. Thanks.

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  • Static struct in C++

    - by pingvinus
    Hi, I want to define an structure, where some math constants would be stored. Here what I've got now: struct consts { //salt density kg/m3 static const double gamma; }; const double consts::gamma = 2350; It works fine, but there would be more than 10 floating point constants, so I doesn't want to wrote 'static const' before each of them. And define something like that: static const struct consts { //salt density kg/m3 double gamma; }; const double consts::gamma = 2350; It look fine, but I got these errors: 1. member function redeclaration not allowed 2. a nonstatic data member may not be defined outside its class I wondering if there any C++ way to do it?

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  • Learning Haskell maps, folds, loops and recursion

    - by Darknight
    I've only just dipped my toe in the world of Haskell as part of my journey of programming enlightenment (moving on from, procedural to OOP to concurrent to now functional). I've been trying an online Haskell Evaluator. However I'm now stuck on a problem: Create a simple function that gives the total sum of an array of numbers. In a procedural language this for me is easy enough (using recursion) (c#) : private int sum(ArrayList x, int i) { if (!(x.Count < i + 1)) { int t = 0; t = x.Item(i); t = sum(x, i + 1) + t; return t; } } All very fine however my failed attempt at Haskell was thus: let sum x = x+sum in map sum [1..10] this resulted in the following error (from that above mentioned website): Occurs check: cannot construct the infinite type: a = a -> t Please bear in mind I've only used Haskell for the last 30 minutes! I'm not looking simply for an answer but a more explanation of it. Thanks in advanced.

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  • Form (or Formset?) to handle multiple table rows in Django

    - by Ben
    Hi, I'm working on my first Django application. In short, what it needs to do is to display a list of film titles, and allow users to give a rating (out of 10) to each film. I've been able to use the {{ form }} and {{ formset }} syntax in a template to produce a form which lets you rate one film at a time, which corresponds to one row in a MySQL table, but how do I produce a form that iterates over all the movie titles in the database and produces a form that lets you rate lots of them at once? At first, I thought this was what formsets were for, but I can't see any way to automatically iterate over the contents of a database table to produce items to go in the form, if you see what I mean. Currently, my views.py has this code: def survey(request): ScoreFormSet = formset_factory(ScoreForm) if request.method == 'POST': formset = ScoreFormSet(request.POST, request.FILES) if formset.is_valid(): return HttpResponseRedirect('/') else: formset = ScoreFormSet() return render_to_response('cf/survey.html', { 'formset':formset, }) And my survey.html has this: <form action="/survey/" method="POST"> <table> {{ formset }} </table> <input type = "submit" value = "Submit"> </form> Oh, and the definition of ScoreForm and Score from models.py are: class Score(models.Model): movie = models.ForeignKey(Movie) score = models.IntegerField() user = models.ForeignKey(User) class ScoreForm(ModelForm): class Meta: model = Score So, in case the above is not clear, what I'm aiming to produce is a form which has one row per movie, and each row shows a title, and has a box to allow the user to enter their score. If anyone can point me at the right sort of approach to this, I'd be most grateful. Thanks, Ben

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  • How is Java Platform independent when it needs JVM to run ?

    - by happysoul
    Just started learning Java and I am confused about this whole independent platform thingy. Doesn't independent means that Java code should be able to run on any machine and would need no special software to be installed (JVM in this case has to be present in the machine)? Like, for example, we need to have Turbo C Compiler in order to compile C/C++ source code and then execute it.. The machine has to have the C compiler. guess I am confused..Somebody please explain in simple language or may be direct me to a tutorial that explain things in simple language ? that would be great I am just not getting the concept.

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  • php array filter

    - by benmsia
    Hi i would like to filter array in php. for example $a = ARRAY('a', 'b', 'c', 'd', 'e'); $b = ARRAY('c', 'd'); $a will be filtered by values in array $b and result is ['a', 'b', 'e'] may I know how to do it in php? Thank you.

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  • ajax code error in aspx page

    - by peter
    where do i put the code in aspx page if i want to display hover menu,,if i put anywhere in aspx page its throwing errors the code is <ajaxToolkit:HoverMenuExtender ID="hme2" runat="Server" TargetControlID="GridView1" PopupControlID="PopupMenu" HoverCssClass="popupHover" PopupPosition="Left" OffsetX="0" OffsetY="0" PopDelay="50" /> errors like unrecoganized tag filter 'ajaxToolkit' ,,,this name contain upper case character which is not allowed,,like that

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  • python regex of a date in some text

    - by Horace Ho
    How can I find as many date patterns as possible from a text file by python? The date pattern is defined as: dd mmm yyyy ^ ^ | | +---+--- spaces where: dd is a two digit number mmm is three-character English month name (e.g. Jan, Mar, Dec) yyyy is four digit year there are two spaces as separators Thanks!

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  • Extremely basic PHP and Mysql

    - by fighella
    Background: I am more of a designer than a programmer, but have hacked templates for many open source CMS's (Drupal, Joomla, Wordpress) I want to start from scratch in regards to the relations of php and a mysql database. Lets assume I have a working database and php engine locally. What would be my first step to connecting to my database and creating a table... (im happy to be led to an appropriate tutorial...) Many of the tutorials I have seen start with basic php, but I would rather explore the connection between the db and the php.

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  • Any difference in compiler behavior for each of these snippets?

    - by HotHead
    Please consider following code: 1. uint16 a = 0x0001; if(a < 0x0002) { // do something } 2. uint16 a = 0x0001; if(a < uint16(0x0002)) { // do something } 3. uint16 a = 0x0001; if(a < static_cast<uint16>(0x0002)) { // do something } 4. uint16 a = 0x0001; uint16 b = 0x0002; if(a < b) { // do something } What compiler does in backgorund and what is the best (and correct) way to do above testing? p.s. sorry, but I couldn't find the better title :) EDIT: values 0x0001 and 0x0002 are only example. There coudl be any 2 byte value instead. Thank you in advance!

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  • gridview column popup window

    - by peter
    i want to implement ajax hover menu and i have a grid gridview1 like this <asp:GridView ID="GridView1" OnRowCommand="ScheduleGridView_RowCommand" runat="server" AutoGenerateColumns="False" Height="60px" Style="text-align: center" Width="869px" EnableViewState="False"> <Columns> <asp:BoundField HeaderText="Topic" DataField="Topic" /> <asp:BoundField DataField="Moderator" HeaderText="Moderator" /> <asp:BoundField DataField="Expert" HeaderText="Expert" /> <asp:BoundField DataField="StartTime" HeaderText="Start"> <HeaderStyle Width="175px" /> </asp:BoundField> <asp:BoundField DataField="EndTime" HeaderText="End"> <HeaderStyle Width="175px" /> </asp:BoundField> <asp:TemplateField HeaderText="Join" ShowHeader="False"> <ItemTemplate> <asp:Button ID="JoinBT" runat="server" CommandName="Join" Text="Join" Width="52px" /> </ItemTemplate> <HeaderStyle Height="15px" /> </asp:TemplateField> </Columns> </asp:GridView> so i registered <%@ Register Assembly="AjaxControlToolkit" Namespace="AjaxControlToolkit" TagPrefix="asp" %> and added I added this way in code of gridview columns But i am getting fixed Edit/delete link in a new column rather than Hover menu,,Can any one tell me the solution to get hover menu

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  • Understanding Device Contexts

    - by Smashery
    As a relative newcomer to MFC, I see Device Contexts (DCs) a lot. I vaguely understand that it's something to do with drawing, but the specifics are not very well explained anywhere that I can find. What does creating a "compatible Device Context" mean, and why is it important? What does SelectObject do, and how must I make a DC compatible first?

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