Search Results

Search found 12766 results on 511 pages for 'genetic programming'.

Page 194/511 | < Previous Page | 190 191 192 193 194 195 196 197 198 199 200 201  | Next Page >

  • how to access child instances in a vector in c++

    - by tsubasa
    I have a parent class and child class (inherited from parent). In the child class, I have a member function named function_blah(); I used vector<parent*> A to store 5 parent instances, 3 child instances. So the total number of elements in the vector is 8. I can easily access to member functions of element A[0] to A[4], which are parent instances. But whenever I try to have access to member functions of element A[5] to A[7], the compiler complains that class parent has no member named 'function_blah' The way I access to elements is using index. e.x A[i] with i = 0..7. Is it correct? if not, how?

    Read the article

  • Wake up thread blocked on accept() call

    - by selbie
    Sockets on Linux question I have a worker thread that is blocked on an accept() call. It simply waits for an incoming network connection, handles it, and then returns to listening for the next connection. When it is time for the program to exit, how do I signal this network worker thread (from the main thread) to return from the accept() call while still being able to gracefully exit its loop and handle it's cleanup code. Some things I tried: 1. pthread_kill to send a signal. Feels kludgy to do this, plus it doesn't reliably allow the thread to do it's shutdown logic. Also makes the program terminate as well. I'd like to avoid signals if at all possible. pthread_cancel. Same as above. It's a harsh kill on the thread. That, and the thread may be doing something else. Closing the listen socket from the main thread in order to make accept() abort. This doesn't reliably work. Some constraints: If the solution involves making the listen socket non-blocking, that is fine. But I don't want to accept a solution that involves the thread waking up via a select call every few seconds to check the exit condition. The thread condition to exit may not be tied to the process exiting. Essentially, the logic I am going for looks like this. void* WorkerThread(void* args) { DoSomeImportantInitialization(); // initialize listen socket and some thread specific stuff while (HasExitConditionBeenSet()==false) { listensize = sizeof(listenaddr); int sock = accept(listensocket, &listenaddr, &listensize); // check if exit condition has been set using thread safe semantics if (HasExitConditionBeenSet()) { break; } if (sock < 0) { printf("accept returned %d (errno==%d)\n", sock, errno); } else { HandleNewNetworkCondition(sock, &listenaddr); } } DoSomeImportantCleanup(); // close listen socket, close connections, cleanup etc.. return NULL; } void SignalHandler(int sig) { printf("Caught CTRL-C\n"); } void NotifyWorkerThreadToExit(pthread_t thread_handle) { // signal thread to exit } int main() { void* ptr_ret= NULL; pthread_t workerthread_handle = 0; pthread_create(&workerthread, NULL, WorkerThread, NULL); signal(SIGINT, SignalHandler); sleep((unsigned int)-1); // sleep until the user hits ctrl-c printf("Returned from sleep call...\n"); SetThreadExitCondition(); // sets global variable with barrier that worker thread checks on // this is the function I'm stalled on writing NotifyWorkerThreadToExit(workerthread_handle); // wait for thread to exit cleanly pthread_join(workerthread_handle, &ptr_ret); DoProcessCleanupStuff(); }

    Read the article

  • Getting started with MIT Proto

    - by Charles
    MIT Proto lacks a basic getting started guide. How do I find a shell that accepts commands like (def foo...) and proto -n 1000 -l -m ...? http://groups.csail.mit.edu/stpg/proto.html I can run in my bash shell: ./proto -n 1000 -s 0.1 -T -l "(red (gradient (= (mid) 0)))" I can't figure out how to run e.g. channel.proto: (def channel (src dst width) (let* ((d (distance src dst)) (trail (<= (+ (gradient src) (gradient dst)) (+ d 0.01))) ;; float error ;; (trail (= (+ (gradient src) (gradient dst)) d)) ) (dilate trail width))) ;; To see a channel calculated from geometric primitives, run: ;; proto -n 1000 -l -m -s 0.5 "(blue (channel (sense 1) (sense 2) 10))" ;; click on a device and hit 't' to set up the source, then click on ;; another device and hit 'y' to designate the destination. At first ;; every device will be blue, but then it should clear and you should ;; see a thick blue path connecting the two devices you selected. Thanks! P.S. Somebody please tag this mit-proto. I can't.

    Read the article

  • please help me to choose good boks on algorithms

    - by davit-datuashvili
    i want to help me to choose good books on algorithms many people from this site say me that show me your code and now i ask u to help me to choose good books on algorithms please i have not books on algorithms and in case i decide to buy it of course must buy book which has high quality yes? so please any ideas ?links everything

    Read the article

  • wireless networks c program

    - by Nave
    i wud like to create a wireless network from a laptop. if some laptops come within this range, i wud like to send them a welcome message and when they leave the wifi range, i send them a bye message. is it possible to code such a thing in C? please help me out with this.

    Read the article

  • Interpreted languages: The higher-level the faster?

    - by immersion
    I have designed around 5 experimental languages and interpreters for them so far, for education, as a hobby and for fun. One thing I noticed: The assembly-like language featuring only subroutines and conditional jumps as structures was much slower than the high-level language featuring if, while and so on. I developed them both simultaneously and both were interpreted languages. I wrote the interpreters in C++ and I tried to optimize the code-execution part to be as fast as possible. My hypothesis: In almost all cases, performance of interpreted languages rises with their level (high/low). Am I basically right with this? (If not, why?)

    Read the article

  • Any good C interpreters?

    - by NoMoreZealots
    I was looking at Ch from SofIntegration and it looks pretty interesting as a possible teaching tool. It would allow the you to let someone learning to program "play" while preparing them to write full fledged C programs. I was wondering if anybody had "good" experiences using a C interpreter or weather it would be a better to go with a language that is typically interpreter to start with?

    Read the article

  • Help Me Make My Pascal Program Display Multiple Names Which Were Entered Plz.

    - by Sketchie
    Hey,Guys I'm having trouble displaying names using arrays in my Pascal program. But first heres the question I'm writing the program to answer : Develop pseudocode that accepts as input the name of an unspecified number of masqueraders who each have paid the full cost of their costume and the amount each has paid. A masquerader may have paid for a costume in any of the five sections in the band. The algorithm should determine the section in which the masquerader plays, based on the amount he/she has paid for the costume. The algorithm should also determine the number of masqueraders who have paid for costumes in each section. The names of persons and the section for which they have paid should be printed. A listing of the sections and the total number of persons registered to play in each section should also be printed, along with the total amount paid in each section. And here's what I've done so far(It's a bit messy): program Maqueprgrm; uses wincrt; type names=array [1..30]of string; var name:string; s1_nms:names; s2_nms:names; s3_nms:names; s4_nms:names; s5_nms:names; amt_paid:integer; stop,x,full,ins,ttl1,ttl2,ttl3,ttl4,ttl5,sec_1,sec_2,sec_3,sec_4,sec_5,sec:integer; begin stop := 0; writeln ('To Begin Data Collecting Section Press 1, To End Press 0'); readln(stop); while stop <0 do begin for x:= 1 to 30 do x:= x+1; writeln ('Please Enter The Name of Masquerader.'); readln (name); writeln ('Please Enter The Amount Paid For Costume.'); readln (amt_paid); IF amt_paid = 144 THEN Begin full:=full+1; {people who paid in full + 1} sec_1:=sec_1+1; {people in this section + 1} ttl1:= ttl1+amt_paid; {total money earned in this section + amount person paid} s1_nms[x]:= name; {People's names in this section plus current entry's name} End else IF amt_paid = 184 then Begin ins:=ins+1; sec_1:=sec_1+1; ttl1:=ttl1+amt_paid; s1_nms[x]:= name; end else IF amt_paid = 198 then Begin full:=full+1; sec_2:=sec_2+1; ttl2:=ttl2+amt_paid; s2_nms[x]:= 'name'; end else IF amt_paid = 153 then Begin ins:=ins+1; sec_2:=sec_2+1; ttl2:=ttl2+amt_paid; s2_nms[x]:= 'name'; end else IF amt_paid = 264 then Begin full:=full+1; sec_3:=sec_3+1; ttl3:=ttl3+amt_paid; s3_nms[x]:= 'name'; end else IF amt_paid = 322 then Begin ins:=ins+1; sec_3:=sec_3+1; ttl3:=ttl3+amt_paid; s3_nms[x]:= 'name'; end else IF amt_paid = 315 then Begin full:=full+1; sec_4:=sec_4+1; ttl4:=ttl4+amt_paid; s4_nms[x]:= 'name'; end else IF amt_paid = 402 then Begin ins:=ins+1; sec_4:=sec_4+1; ttl4:=ttl4+amt_paid; s4_nms[x]:= 'name'; end else IF amt_paid = 382. then Begin ins:=ins+1; sec_4:=sec_4+1; ttl4:=ttl4+amt_paid; s4_nms[x]:= 'name'; end else IF amt_paid = 488 then Begin ins:=ins+1; sec_5:=sec_5+1; ttl5:=ttl5+amt_paid; s5_nms[x]:= 'name'; end else begin Writeln ('Invalid Entry'); For x:= 1 to 30 do end; writeln (' To Enter More Data Press 1, To Print Data and Calculations Press 0'); Readln (stop); End; writeln ('For Information on Sections Press 1, 2, 3, 4, or 5 Respectively'); Readln (sec); IF Sec= 1 THEN Begin for x:= 1 to 30 do; begin writeln ('The Number of Revelers in This Section is ',Sec_1,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins ,'.'); Writeln ('The Names of Revelers in This Section is ', S1_Nms[x], '.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl1, '.'); End; end else IF Sec= 2 THEN Begin For x:= 1 to 30 do begin Writeln ('The Number of Revelers in This Section is ', Sec_2,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins ,'.'); Writeln ('The Names of Revelers in This Section is ', S2_Nms[x] ,'.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl2, '.'); End; End else IF Sec= 3 THEN Begin For x:= 1 to 30 do begin writeln ('The Number of Revelers in This Section is ', Sec_3,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins ,'.'); Writeln ('The Names of Revelers in This Section is ', S3_Nms[x] ,'.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl3, '.'); End; End else IF Sec= 4 THEN Begin For x:= 1 to 30 do begin writeln ('The Number of Revelers in This Section is ', Sec_4,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins, '.'); Writeln ('The Names of Revelers in This Section is ', S4_Nms [x],'.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl4 ,'.'); End; End else IF Sec= 5 THEN Begin For x:= 1 to 30 do begin writeln ('The Number of Revelers in This Section is ', Sec_5,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Full Is ', Full,'.'); Writeln ('The Number of Revelers in the Band Who Paid in Installments is ', Ins, '.'); Writeln ('The Names of Revelers in This Section is ', S5_Nms[x], '.'); Writeln ('The Total Amount Collected By This Section Is ', Ttl5 ,'.'); End; End else BEGIN Writeln ('Invalid Entry. For Information on Sections Press 1, 2, 3, 4, or 5 Respectively. '); End; end. The result I keep getting is that for the names in the section it is only the name of the last person entered that is displayed. For example it would display: The number of revelers in this section is 2 The number of revelers in the band who paid in full is 2 {Band is the whole thing divided into 5 section} The number of revelers in the band who paid in installments is 0 The names of revelers in this section is Amy Total amount collected by this section is 288 So yea, the program only displays "Amy" even though I entered more than 1 name. Do you guys know how to fix it also if it's not asking too much could you help me to make a while loop for the last portion of the program so that after the user sees the info for a section he can see another section. It sucks that I've been working on it for a while but if it doesn't run properly tomorrow I'll fail. Help would be greatly appreciated and responses are welcome anytime cause i'll be up anyway. P.S. Sorry for the long post.

    Read the article

  • How to implement a UIViewAutoresizingFlexibleHeight to a UIScrollView using Objective C in iPhone SD

    - by AppleHack23
    Hello, I'm working on multiple applications for my school. I just need this last bit of code and I was wondering how I could implement a UIViewAutoresizingFlexibleHeight into the app for each textfield. What this does is it makes the textfield pop above the keyboard, rather than over lapping it. I have already implemented a UIScrollView, so if someone on here could be pretty descriptive, or post a link to a video, that would be well appreciated. I am new to coding. Thanks very much!!!!

    Read the article

  • Why does Ordered[A] use a compare method instead of reusing compareTo?

    - by soc
    trait Ordered[A] extends java.lang.Comparable[A] { def compare(that: A): Int def < (that: A): Boolean = (this compare that) < 0 def > (that: A): Boolean = (this compare that) > 0 def <= (that: A): Boolean = (this compare that) <= 0 def >= (that: A): Boolean = (this compare that) >= 0 def compareTo(that: A): Int = compare(that) } Isn't it a bit useless to have both compare and compareTo? What is the huge benefit I'm missing here? If they had just used compareTo I could just had replaced Comparable with Ordered in my code and be done.

    Read the article

  • Abstract over X

    - by Bruno Bieth
    Sorry for this english related question but I only came across that expression in the context of IT. What does abstracting over something mean ? For example abstracting over objects or abstracting over classes. Thanks

    Read the article

  • CSS Brace Styles

    - by Nimbuz
    I'm unable to figure how the standard (or just popular) brace style names apply to CSS. Here're all the brace styles: /* one - pico? */ selector { property: value; property: value; } /* two */ selector { property: value; /* declaration starts on newline */ property: value; } /* three */ selector { property: value; property: value; } /* four - Allman or GNU?*/ selector { property: value; /* declaration starts on newline */ property: value; }? /* five */ selector { property: value; property: value; } /* six - horstmann? */ selector { property: value; /* declaration starts on newline */ property: value; } /* seven - banner?*/ selector { property: value; property: value; } /* eight */ selector { property: value; /* declaration starts on newline */ property: value; } Can someone please name each brace style for me? Many thanks!

    Read the article

  • How to get input from web?

    - by Dunix
    Hi, i am trying to find out, how to get input from html inputs using c++. In windows you can send WM_GETTEXT to the window and it returns text, that you wanted. But is there any way to do the same thing in web interface?. I am not interesting in sniffing packets now.

    Read the article

  • How do I have my apps dialog box pop up and take focus from the current running app?

    - by simba
    I know this type of thing is looked negatively upon but I write software for people with disabilities and sometimes good gui practices don't make sense. In this case, the user interacts with a assistive interface and under certain conditions, my control app needs to prompt the user with a question. My background process creates a dialog (I'm using wxwidgets wxDialog class) and calls Show(). The dialog box appears but it does not have focus (the application that the user was previously using keeps it). Since my users can't use mice, they can't simply click on the window. I've tried calling show and then followed by SetFocus(HWND) but that doesn't do it. What's the problem? Is this even possible? Window7. I'm thinking that it might have something to do with it being a dialog and not a full window (wxFrame). Any help is greatly appreciated.

    Read the article

  • Python: Calling method A from class A within class B?

    - by Tommo
    There are a number of questions that are similar to this, but none of the answers hits the spot - so please bear with me. I am trying my hardest to learn OOP using Python, but i keep running into errors (like this one) which just make me think this is all pointless and it would be easier to just use methods. Here is my code: class TheGUI(wx.Frame): def __init__(self, title, size): wx.Frame.__init__(self, None, 1, title, size=size) # The GUI is made ... textbox.TextCtrl(panel1, 1, pos=(67,7), size=(150, 20)) button1.Bind(wx.EVT_BUTTON, self.button1Click) self.Show(True) def button1Click(self, event): #It needs to do the LoadThread function! class WebParser: def LoadThread(self, thread_id): #It needs to get the contents of textbox! TheGUI = TheGUI("Text RPG", (500,500)) TheParser = WebParser TheApp.MainLoop() So the problem i am having is that the GUI class needs to use a function that is in the WebParser class, and the WebParser class needs to get text from a textbox that exists in the GUI class. I know i could do this by passing the objects around as parameters, but that seems utterly pointless, there must be a more logical way to do this that doesn't using classes seem so pointless? Thanks in advance!

    Read the article

< Previous Page | 190 191 192 193 194 195 196 197 198 199 200 201  | Next Page >