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  • exception in thread "main" java.lang.NoclassDefFoundError: cal/class

    - by Gaurav
    enter import java.io.*; class eval { double add(double a,double b) { return (a+b); } double sub(double a,double b) { return (a-b); } double mul(double a,double b) { return (a*b); } double div(double a,double b) { return (a/b); } } class cal extends eval { public static void main(String args[])throws IOException { eval a1=new eval(); try{ System.out.println("1) Add"); System.out.println("2) Subtract"); System.out.println("3) Multiply"); System.out.println("4) Divide"); System.out.println("5) Enter your choice"); BufferedReader br=new BufferedReader(new InputStreamReader(System.in)); int ch;ch=Integer.parseInt(br.readLine()); System.out.println("Enter two number"); double a;a=Integer.parseInt(br.readLine()); double b;b=Integer.parseInt(br.readLine()); switch(ch) { case 1: a1.add(a,b); break; case 2: a1.sub(a,b); break; case 3: a1.mul(a,b); break; case 4: a1.div(a,b); break; } } catch (IOException e) { System.out.println("Error occured, please restart application."); } } }

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  • Splitting a C++ class into files now won't compile.

    - by vgm64
    Hi. I am teaching myself to write classes in C++ but can't seem to get the compilation to go through. If you can help me figure out not just how, but why, it would be greatly appreciated. Thank you in advance! Here are my three files: make_pmt.C #include <iostream> #include "pmt.h" using namespace std; int main() { CPMT *pmt = new CPMT; pmt->SetVoltage(900); pmt->SetGain(2e6); double voltage = pmt->GetVoltage(); double gain= pmt->GetGain(); cout << "The voltage is " << voltage << " and the gain is " << gain << "." <<endl; return 0; } pmt.C #include "pmt.h" using namespace std; class CPMT { double gain, voltage; public: double GetGain() {return gain;} double GetVoltage() {return voltage;} void SetGain(double g) {gain=g;} void SetVoltage(double v) {voltage=v;} }; pmt.h #ifndef PMT_H #define PMT_H 1 using namespace std; class CPMT { double gain, voltage; public: double GetGain(); double GetVoltage(); void SetGain(double g); void SetVoltage(double v); }; #endif And for reference, I get a linker error (right?): Undefined symbols: "CPMT::GetVoltage()", referenced from: _main in ccoYuMbH.o "CPMT::GetGain()", referenced from: _main in ccoYuMbH.o "CPMT::SetVoltage(double)", referenced from: _main in ccoYuMbH.o "CPMT::SetGain(double)", referenced from: _main in ccoYuMbH.o ld: symbol(s) not found collect2: ld returned 1 exit status

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  • How to replace 'dash' with 'underscore' in an IIRF rule?

    - by jessegavin
    I have a web app which serves images based on the subdomain. We wanted to provide our users with a url like this: http://{username}.domain.com/images/myimage.jpg Instead of what we used to have: http://www.reallylongdomainname.com/users/{username}/images/myimage.jpg This makes the url shorter and less 'snoopable'. So I set up an IIRF .ini file to do some url rewriting and it works great except for the fact that some of our users folders have an underscore. And from what I've read, underscore is not a valid character in a domain name (even though IIS supports it). I want to know how I could do a find and replace in the $1 back reference so that a url like this: http://some-user.domain.com/... Could be rewritten to this: /users/some_user/.. Here's my IIRF rule. RewriteCond %{HTTP_HOST} ^(?!www)([^\.]+)\.domain\.com RewriteRule ^/(.*)$ /users/*1/$1 [L,I] Thanks for any help.

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  • C++: Error in Xcode; "Graph::Coordinate::Coordinate()", referenced from: ...

    - by Alexandstein
    In a program I am writing, I wrote for two classes (Coordinate, and Graph), with one of them taking the other as constructor arguments. When I try to compile it I get the following error for Graph.cpp: Undefined symbols: "Graph::Coordinate::Coordinate(double)", referenced from: Graph::Graph() in Graph.o Graph::Graph() in Graph.o "Graph::Coordinate::Coordinate()", referenced from: Graph::Graph(Graph::Coordinate, Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate, Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate)in Graph.o Graph::Graph(Graph::Coordinate)in Graph.o Graph::Graph() in Graph.o Graph::Graph() in Graph.o Graph::Graph() in Graph.o Graph::Graph() in Graph.o Graph::Graph() in Graph.o Graph::Graph() in Graph.o ld: symbol(s) not found collect2: ld returned 1 exit status I checked the code and couldn't find anything out of the ordinary. Here are the four class files: (Sorry if it's a lot of code to sift through.) Coordinate.h class Graph{ #include "Coordinate.h" public: Graph(); Graph(Coordinate); Graph(Coordinate, Coordinate); Graph(Coordinate, Coordinate, Coordinate); void setXSize(int); void setYSize(int); void setX(int); //int corresponds to coordinates 1, 2, or 3 void setY(int); void setZ(int); int getXSize(); int getYSize(); double getX(int); //int corresponds to coordinates 1, 2, or 3 double getY(int); double getZ(int); void outputGraph(); void animateGraph(); private: int xSize; int ySize; Coordinate coord1; Coordinate coord2; Coordinate coord3; }; Coordinate.cpp #include <iostream> #include "Coordinate.h" Coordinate::Coordinate() { xCoord = 1; yCoord = 1; zCoord = 1; xVel = 1; yVel = 1; zVel = 1; } Coordinate::Coordinate(double xCoo) { xCoord = xCoo; yCoord = 1; zCoord = 1; xVel = 1; yVel = 1; zVel = 1; } Coordinate::Coordinate(double xCoo,double yCoo) { xCoord = xCoo; yCoord = yCoo; zCoord = 1; xVel = 1; yVel = 1; zVel = 1; } Coordinate::Coordinate(double xCoo,double yCoo,double zCoo) { xCoord = xCoo; yCoord = yCoo; zCoord = zCoo; xVel = 1; yVel = 1; zVel = 1; } void Coordinate::setXCoord(double xCoo) { xCoord = xCoo; } void Coordinate::setYCoord(double yCoo) { yCoord = yCoo; } void Coordinate::setZCoord(double zCoo) { zCoord = zCoo; } void Coordinate::setXVel(double xVelo) { xVel = xVelo; } void Coordinate::setYVel(double yVelo) { yVel = yVelo; } void Coordinate::setZVel(double zVelo) { zVel = zVelo; } double Coordinate::getXCoord() { return xCoord; } double Coordinate::getYCoord() { return yCoord; } double Coordinate::getZCoord() { return zCoord; } double Coordinate::getXVel() { return xVel; } double Coordinate::GetYVel() { return yVel; } double Coordinate::GetZVel() { return zVel; } Graph.h class Graph{ #include "Coordinate.h" public: Graph(); Graph(Coordinate); Graph(Coordinate, Coordinate); Graph(Coordinate, Coordinate, Coordinate); void setXSize(int); void setYSize(int); void setX(int); //int corresponds to coordinates 1, 2, or 3 void setY(int); void setZ(int); int getXSize(); int getYSize(); double getX(int); //int corresponds to coordinates 1, 2, or 3 double getY(int); double getZ(int); void outputGraph(); void animateGraph(); private: int xSize; int ySize; Coordinate coord1; Coordinate coord2; Coordinate coord3; }; Graph.cpp #include "Graph.h" #include "Coordinate.h" #include <iostream> #include <ctime> using namespace std; Graph::Graph() { Coordinate coord1(0); } Graph::Graph(Coordinate cOne) { coord1 = cOne; xSize = 20; ySize = 20; } Graph::Graph(Coordinate cOne, Coordinate cTwo) { coord1 = cOne; coord2 = cTwo; xSize = 20; ySize = 20; } Graph::Graph(Coordinate cOne, Coordinate cTwo, Coordinate cThree) { coord1 = cOne; coord2 = cTwo; coord3 = cThree; xSize = 20; ySize = 20; } void Graph::setXSize(int size) { xSize = size; } void Graph::setYSize(int size) { ySize = size; } int Graph::getXSize() { return xSize; } int Graph::getYSize() { return ySize; } void Graph::outputGraph() { } void Graph::animateGraph() { } Thanks very much for any help!

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  • Autocorrelation returns random results with mic input (using a high pass filter)

    - by Niall
    Hello, Sorry to ask a similar question to the one i asked before (FFT Problem (Returns random results)), but i've looked up pitch detection and autocorrelation and have found some code for pitch detection using autocorrelation. Im trying to do pitch detection of a users singing. Problem is, it keeps returning random results. I've got some code from http://code.google.com/p/yaalp/ which i've converted to C++ and modified (below). My sample rate is 2048, and data size is 1024. I'm detecting pitch of both a sine wave and mic input. The frequency of the sine wave is 726.0, and its detecting it to be 722.950820 (which im ok with), but its detecting the pitch of the mic as a random number from around 100 to around 1050. I'm now using a High pass filter to remove the DC offset, but it's not working. Am i doing it right, and if so, what else can i do to fix it? Any help would be greatly appreciated! double* doHighPassFilter(short *buffer) { // Do FFT: int bufferLength = 1024; float *real = malloc(bufferLength*sizeof(float)); float *real2 = malloc(bufferLength*sizeof(float)); for(int x=0;x<bufferLength;x++) { real[x] = buffer[x]; } fft(real, bufferLength); for(int x=0;x<bufferLength;x+=2) { real2[x] = real[x]; } for (int i=0; i < 30; i++) //Set freqs lower than 30hz to zero to attenuate the low frequencies real2[i] = 0; // Do inverse FFT: inversefft(real2,bufferLength); double* real3 = (double*)real2; return real3; } double DetectPitch(short* data) { int sampleRate = 2048; //Create sine wave double *buffer = malloc(1024*sizeof(short)); double amplitude = 0.25 * 32768; //0.25 * max length of short double frequency = 726.0; for (int n = 0; n < 1024; n++) { buffer[n] = (short)(amplitude * sin((2 * 3.14159265 * n * frequency) / sampleRate)); } doHighPassFilter(data); printf("Pitch from sine wave: %f\n",detectPitchCalculation(buffer, 50.0, 1000.0, 1, 1)); printf("Pitch from mic: %f\n",detectPitchCalculation(data, 50.0, 1000.0, 1, 1)); return 0; } // These work by shifting the signal until it seems to correlate with itself. // In other words if the signal looks very similar to (signal shifted 200 data) than the fundamental period is probably 200 data // Note that the algorithm only works well when there's only one prominent fundamental. // This could be optimized by looking at the rate of change to determine a maximum without testing all periods. double detectPitchCalculation(double* data, double minHz, double maxHz, int nCandidates, int nResolution) { //-------------------------1-------------------------// // note that higher frequency means lower period int nLowPeriodInSamples = hzToPeriodInSamples(maxHz, 2048); int nHiPeriodInSamples = hzToPeriodInSamples(minHz, 2048); if (nHiPeriodInSamples <= nLowPeriodInSamples) printf("Bad range for pitch detection."); if (1024 < nHiPeriodInSamples) printf("Not enough data."); double *results = new double[nHiPeriodInSamples - nLowPeriodInSamples]; //-------------------------2-------------------------// for (int period = nLowPeriodInSamples; period < nHiPeriodInSamples; period += nResolution) { double sum = 0; // for each sample, find correlation. (If they are far apart, small) for (int i = 0; i < 1024 - period; i++) sum += data[i] * data[i + period]; double mean = sum / 1024.0; results[period - nLowPeriodInSamples] = mean; } //-------------------------3-------------------------// // find the best indices int *bestIndices = findBestCandidates(nCandidates, results, nHiPeriodInSamples - nLowPeriodInSamples - 1); //note findBestCandidates modifies parameter // convert back to Hz double *res = new double[nCandidates]; for (int i=0; i < nCandidates;i++) res[i] = periodInSamplesToHz(bestIndices[i]+nLowPeriodInSamples, 2048); double pitch2 = res[0]; free(res); free(results); return pitch2; } /// Finds n "best" values from an array. Returns the indices of the best parts. /// (One way to do this would be to sort the array, but that could take too long. /// Warning: Changes the contents of the array!!! Do not use result array afterwards. int* findBestCandidates(int n, double* inputs,int length) { //int length = inputs.Length; if (length < n) printf("Length of inputs is not long enough."); int *res = new int[n]; double minValue = 0; for (int c = 0; c < n; c++) { // find the highest. double fBestValue = minValue; int nBestIndex = -1; for (int i = 0; i < length; i++) { if (inputs[i] > fBestValue) { nBestIndex = i; fBestValue = inputs[i]; } } // record this highest value res[c] = nBestIndex; // now blank out that index. if(nBestIndex!=-1) inputs[nBestIndex] = minValue; } return res; } int hzToPeriodInSamples(double hz, int sampleRate) { return (int)(1 / (hz / (double)sampleRate)); } double periodInSamplesToHz(int period, int sampleRate) { return 1 / (period / (double)sampleRate); } Thanks, Niall. Edit: Changed the code to implement a high pass filter with a cutoff of 30hz (from What Are High-Pass and Low-Pass Filters?, can anyone tell me how to convert the low-pass filter using convolution to a high-pass one?) but it's still returning random results. Plugging it into a VST host and using VST plugins to compare spectrums isn't an option to me unfortunately.

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  • Calculating pi using infinite series in C#

    - by Jonathan Chan
    Hi! I tried to write the following program in C# to calculate pi using infinite recursion, but I keep getting confused about integer/double/decimal division. I really have no clue why this isn't working, so pardon me for my lack of understanding of strongly typed stuff, as I'm still learning C#. Thanks in advance! using System; using System.Collections.Generic; using System.Linq; using System.Text; namespace ConsoleApplication1 { class Program { public static int Main(string[] args) { int numeratornext = 2; int denominatornext = 5; decimal findto = 100.0M; decimal pi = 0.0M; decimal halfpi = 1.0M; int seriesnum = 1; int seriesden = 3; for (int i = 0; i < findto; i++) { halfpi += Decimal.Divide((decimal)seriesnum, (decimal)seriesden); //System.Console.WriteLine(Decimal.Divide((decimal)seriesnum, (decimal)seriesden).ToString()); seriesnum *= numeratornext; seriesden *= denominatornext; numeratornext++; denominatornext += 2; } pi = halfpi * 2; System.Console.WriteLine(pi.ToString()); System.Console.ReadLine(); return 0; } } }

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  • jquery newbie: combine validate with hidding submit button.

    - by Jeffb
    I'm new a jQuery. I have gotten validate to work with my form (MVC 1.0 / C#) with this: <script type="text/javascript"> if (document.forms.length > 0) { document.forms[0].id = "PageForm"; document.forms[0].name = "PageForm"; } $(document).ready(function() { $("#PageForm").validate({ rules: { SigP: { required: true } }, messages: { SigP: "<font color='red'><b>A Sig Value is required. </b></font>" } }); }); </script> I also want to hide the Submit button to prevent twitchy mouse syndrome from causing duplicate entry before the controller completes and redirects (I'm using an GPR pattern). The following works for this purpose: <script type="text/javascript"> // // prevent double-click on submit // jQuery('input[type=submit]').click(function() { if (jQuery.data(this, 'clicked')) { return false; } else { jQuery.data(this, 'clicked', true); return true; } }); </script> However, I can't get the two to work together. Specifically, if validate fails after the Submit button is clicked (which happens given how the form works), then I can't get the form submitted again unless I do a browser refresh that resets the 'clicked' property. How can I rewrite the second method above to not set the clicked property unless the form validates? Thx.

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  • Prevent Rails link_to_remote multiple submits w Javascript

    - by Chris
    In a Rails project I need to keep a link_to_remote from getting double-clicked. It looks like :before and :after are my only choices - they get prepended/appended to the onclick Ajax call, respectively. But if I try something like: :before => "self.stopObserving()" t,he Ajax is never run. If I try it for :after the Ajax is run but the link never stops observing. The solutions I've seen rely on creating a variable and blocking the whole form, but there are multiple link_to_remote rows on this page and it is valid to click more than one of them at a time - just not the same one twice. One variable per row declared outside of link_to_remote seems very kludgey... Instead of using Prototype I originally tried plain Javascript first for this proof of concept - but it fails too: <a href="#" onclick="self.onclick = function(){alert('foo');};"click</a just puts up an alert when clicked - the lambda here does nothing? This next one is more like the desired goal and should only alert the first time. But instead it alerts every time: <a href="#" onclick="alert('bar'); self.onclick = function(){return false;};"click</a All ideas appreciated!

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  • How many significant digits should I use for double literals in Java?

    - by M. Dudley
    How many significant digits should I use when defining a double literal in Java? This is assuming that I am trying to represent a number with more significant figures than a double can hold. In Math.java I see 20 and 21: public static final double E = 2.7182818284590452354; public static final double PI = 3.14159265358979323846; This is more than the 15-17 significant digits provided by IEEE 754. So what's the general rule-of-thumb?

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  • Nautilus won't browse my USB hard drive unless I double click it twice.

    - by agnul
    On my laptop, running 10.10, whenever I plug in a thumb drive Nautilus will add an icon on the desktop and open a file manager window with the drive contents. This does not work for my 250Mb external hard drive: the icon is added on the desktop, but no file manager window pops up. Double clicking on the icon just causes some disk activity (on the system drive) and nothing else. Double clicking another time on the icon the file manager eventually opens. At first I thought this was related to nautilus-elementary, but after removing nothing has changed. How do I even start debugging this?

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  • Un iPhone 5 pour septembre ? Il embarquerait un processeur double coeur A5 et iOS 5

    Un iPhone 5 pour septembre ? Il embarquerait un processeur double coeur A5 et iOS 5 Selon Bloomberg, Apple devrait lancer officiellement son nouvel iPhone (iPhone 4S ou iPhone 5) en septembre prochain. La prochaine version du smartphone sera équipée du processeur double coeur A5 déjà à l'oeuvre dans l'iPad2. Ce processeur devrait améliorer considérablement la vitesse d'exécution des applications iPhone. L'iPhone 5 disposera par ailleurs d'un appareil photo de 8 mégapixels au lieu de 5 sur l'iPhone 4. Côté OS, le smartphone sera équipé - sans surprise - d'iOS 5, dévoilé au début du mois lors du WWDC. Le nouvel OS, a...

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  • Windows Store compte 2452 applications à 1 mois du lancement de Windows 8, la galerie double de volume en 10 jours

    Windows Store compte 2 452 applications à 1 mois du lancement de Windows 8, la galerie double de volume en 10 jours L'engouement des développeurs pour Windows 8 semble se confirmer. Après un coding marathon qui a enregistré le plus fort taux de participation des développeurs à une compétition de développement, l'OS voit le nombre d'applications dans son store doublé en seulement 10 jours. À un mois de la sortie grand public de Windows 8, sa galerie d'application disposerait déjà de 2452 applications le 26 septembre. La galerie qui proposait 530 applications le 16 août, a franchi le cap des 1000 app...

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  • How do I change variables from different classes?

    - by Dan T
    Before I delve into it, I'm very new to Android and I have just started learning Java last month. I've hit bumps while trying to develop my first simple app. Most of these hurdles were jumped thanks to random tutorials online. MY CODE IS VERY MESSY. Any tips are appreciated. The question above is quite broad, but this is what I want to do: It's a essentially a blood alcohol content calculator / drink keeper-tracker. Basic layout: http://i.imgur.com/JGuh7.jpg The buttons along the bottom are just regular buttons, not ImageButtons (had problems with that) Here's some example code of one: <Button android:id="@+id/Button01" android:layout_width="wrap_content" android:layout_marginRight="5dp" android:background="@drawable/addbeer"/> The buttons and TextView are all in main.xml. I have variables defined in a class called Global.java: package com.dantoth.drinkingbuddy; import android.app.Activity; public class Global extends Activity{ public static double StandardDrinks = 0; public static double BeerOunces = 12; public static double BeerPercentAlcohol = .05; public static double BeerDrink = BeerOunces * BeerPercentAlcohol; public static double BeerDrinkFinal = BeerDrink * 1.6666666; public static double ShotOunces = 1.5; public static double ShotPercentAlcohol = .4; public static double ShotDrink = ShotOunces * ShotPercentAlcohol; public static double ShotDrinkFinal = ShotDrink * 1.6666666; public static double WineOunces = 5; public static double WinePercentAlcohol = .12; public static double WineDrink = WineOunces * WinePercentAlcohol; public static double WineDrinkFinal = WineDrink * 1.6666666; public static double OtherOunces; public static double OtherPercentAlcohol; public static double OtherDrink = OtherOunces * (OtherPercentAlcohol * .01); public static double OtherDrinkFinal = OtherDrink * 1.6666666; public static double GenderConstant = 7.5; //9 for female public static double Weight = 180; public static double TimeDrinking = 60; public static double Hours = TimeDrinking / 60; public static double Bac = ((StandardDrinks / 2) * (GenderConstant / Weight)) - (0.017 * Hours); } The last variable is the important part. It calculates your BAC based on the factors involved. When I press the add beer button (Button01) I make it add 1 to StandardDrinks, simulating drinking one beer. The other variables in the Bac formula have values assigned to them in Global.java. The code that makes the beer button do stuff is in my regular class, drinkingbuddy.java: public class DrinkingBuddy extends Activity { /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); Button button = (Button) findViewById(R.id.Button01); button.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { Global.StandardDrinks = Global.StandardDrinks + Global.BeerDrinkFinal; Toast.makeText(DrinkingBuddy.this, "Mmmm... Beer", Toast.LENGTH_SHORT).show(); } }); By my perception, StandardDrinks should now have a value of 1. However, when I click the Calculate BAC button (Button05) it merely outputs the variable Bac as if StandardDrinks was still set to 0. Here is the code for the Calculate BAC button (Button05): Button button4 = (Button) findViewById(R.id.Button05); button4.setOnClickListener(new OnClickListener() { @Override public void onClick(View v) { TextView texty; texty = (TextView) findViewById(R.id.texty1); texty.setText("Your BAC is " + Global.Bac ); } }); It outputs the following to the text view: "Your BAC is -0.017". This is the Bac value for if StandardDrinks was still 0, so obviously there is some problem communicating between the classes. Can anyone help me?? The other elements of the formula (weight, time spent drinking, and the alcohol %'s and such) are variables because I will ultimately allow the user to change those values in the settings. I've heard around the water cooler that global variables are not good programming style, but this is the closest I've come to getting it to work. Any other ways of doing it are very much welcomed!

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  • Struct in C, are they efficient?

    - by pygabriel
    I'm reading some C code like that: double function( int lena,double xa,double ya, double za, double *acoefs, ..., int lenb,double xb,double yb, double zb, double *bcoefs, ..., same for c, same for d ) This function is called in the code mor than 100.000 times so it's performance-critical. I'm trying to extend this code but I want to know if it's efficient or not (and how much this influences the speed) to encapsulate all the parameters in a struct like this struct PGTO { int len; double x,y,z ; double *acoefs } and then access the parameters in the function.

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  • Why do C compilers prepend underscores to external names?

    - by Michael Burr
    I've been working in C for so long that the fact that compilers typically add an underscore to the start of an extern is just understood... However, another SO question today got me wondering about the real reason why the underscore is added. A wikipedia article claims that a reason is: It was common practice for C compilers to prepend a leading underscore to all external scope program identifiers to avert clashes with contributions from runtime language support I think there's at least a kernel of truth to this, but also it seems to no really answer the question, since if the underscore is added to all externs it won't help much with preventing clashes. Does anyone have good information on the rationale for the leading underscore? Is the added underscore part of the reason that the Unix creat() system call doesn't end with an 'e'? I've heard that early linkers on some platforms had a limit of 6 characters for names. If that's the case, then prepending an underscore to external names would seem to be a downright crazy idea (now I only have 5 characters to play with...).

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  • C lang. -- Error: Segmentaion fault

    - by user233542
    I don't understand why this would give me a seg fault. Any ideas? this is the function that returns the signal to stop the program: (below is the other function that is called within this) double bisect(double A0,double A1,double Sol[N],double tol,double c) { double Amid,shot; while (A1-A0 tol) { Amid = 0.5*(A0+A1); shot = shoot(Sol, Amid, c); if (shot==2.*Pi) { return Amid; } if (shot > 2.*Pi){ A1 = Amid; } else if (shot < 2.*Pi){ A0 = Amid; } } return 0.5*(A1+A0); } double shoot(double Sol[N],double A,double c) { int i,j; /Initial Conditions/ for (i=0;i for (i=buff+2;i return Sol[i-1]; } buff, l, N are defined using a #deine statement. l = 401, buff = 50, N = 2000 Thanks

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  • Valgrind says "stack allocation," I say "heap allocation"

    - by Joel J. Adamson
    Dear Friends, I am trying to trace a segfault with valgrind. I get the following message from valgrind: ==3683== Conditional jump or move depends on uninitialised value(s) ==3683== at 0x4C277C5: sparse_mat_mat_kron (sparse.c:165) ==3683== by 0x4C2706E: rec_mating (rec.c:176) ==3683== by 0x401C1C: age_dep_iterate (age_dep.c:287) ==3683== by 0x4014CB: main (age_dep.c:92) ==3683== Uninitialised value was created by a stack allocation ==3683== at 0x401848: age_dep_init_params (age_dep.c:131) ==3683== ==3683== Conditional jump or move depends on uninitialised value(s) ==3683== at 0x4C277C7: sparse_mat_mat_kron (sparse.c:165) ==3683== by 0x4C2706E: rec_mating (rec.c:176) ==3683== by 0x401C1C: age_dep_iterate (age_dep.c:287) ==3683== by 0x4014CB: main (age_dep.c:92) ==3683== Uninitialised value was created by a stack allocation ==3683== at 0x401848: age_dep_init_params (age_dep.c:131) However, here's the offending line: /* allocate mating table */ age_dep_data->mtable = malloc (age_dep_data->geno * sizeof (double *)); if (age_dep_data->mtable == NULL) error (ENOMEM, ENOMEM, nullmsg, __LINE__); for (int j = 0; j < age_dep_data->geno; j++) { 131=> age_dep_data->mtable[j] = calloc (age_dep_data->geno, sizeof (double)); if (age_dep_data->mtable[j] == NULL) error (ENOMEM, ENOMEM, nullmsg, __LINE__); } What gives? I thought any call to malloc or calloc allocated heap space; there is no other variable allocated here, right? Is it possible there's another allocation going on (the offending stack allocation) that I'm not seeing? You asked to see the code, here goes: /* Copyright 2010 Joel J. Adamson <[email protected]> $Id: age_dep.c 1010 2010-04-21 19:19:16Z joel $ age_dep.c:main file Joel J. Adamson -- http://www.unc.edu/~adamsonj Servedio Lab University of North Carolina at Chapel Hill CB #3280, Coker Hall Chapel Hill, NC 27599-3280 This file is part of an investigation of age-dependent sexual selection. This code is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This software is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with haploid. If not, see <http://www.gnu.org/licenses/>. */ #include "age_dep.h" /* global variables */ extern struct argp age_dep_argp; /* global error message variables */ char * nullmsg = "Null pointer: %i"; /* error message for conversions: */ char * errmsg = "Representation error: %s"; /* precision for formatted output: */ const char prec[] = "%-#9.8f "; const size_t age_max = AGEMAX; /* maximum age of males */ static int keep_going_p = 1; int main (int argc, char ** argv) { /* often used counters: */ int i, j; /* read the command line */ struct age_dep_args age_dep_args = { NULL, NULL, NULL }; argp_parse (&age_dep_argp, argc, argv, 0, 0, &age_dep_args); /* set the parameters here: */ /* initialize an age_dep_params structure, set the members */ age_dep_params_t * params = malloc (sizeof (age_dep_params_t)); if (params == NULL) error (ENOMEM, ENOMEM, nullmsg, __LINE__); age_dep_init_params (params, &age_dep_args); /* initialize frequencies: this initializes a list of pointers to initial frqeuencies, terminated by a NULL pointer*/ params->freqs = age_dep_init (&age_dep_args); params->by = 0.0; /* what range of parameters do we want, and with what stepsize? */ /* we should go from 0 to half-of-theta with a step size of about 0.01 */ double from = 0.0; double to = params->theta / 2.0; double stepsz = 0.01; /* did you think I would spell the whole word? */ unsigned int numparts = floor(to / stepsz); do { #pragma omp parallel for private(i) firstprivate(params) \ shared(stepsz, numparts) for (i = 0; i < numparts; i++) { params->by = i * stepsz; int tries = 0; while (keep_going_p) { /* each time through, modify mfreqs and mating table, then go again */ keep_going_p = age_dep_iterate (params, ++tries); if (keep_going_p == ERANGE) error (ERANGE, ERANGE, "Failure to converge\n"); } fprintf (stdout, "%i iterations\n", tries); } /* for i < numparts */ params->freqs = params->freqs->next; } while (params->freqs->next != NULL); return 0; } inline double age_dep_pmate (double age_dep_t, unsigned int genot, double bp, double ba) { /* the probability of mating between these phenotypes */ /* the female preference depends on whether the female has the preference allele, the strength of preference (parameter bp) and the male phenotype (age_dep_t); if the female lacks the preference allele, then this will return 0, which is not quite accurate; it should return 1 */ return bits_isset (genot, CLOCI)? 1.0 - exp (-bp * age_dep_t) + ba: 1.0; } inline double age_dep_trait (int age, unsigned int genot, double by) { /* return the male trait, a function of the trait locus, age, the age-dependent scaling parameter (bx) and the males condition genotype */ double C; double T; /* get the male's condition genotype */ C = (double) bits_popcount (bits_extract (0, CLOCI, genot)); /* get his trait genotype */ T = bits_isset (genot, CLOCI + 1)? 1.0: 0.0; /* return the trait value */ return T * by * exp (age * C); } int age_dep_iterate (age_dep_params_t * data, unsigned int tries) { /* main driver routine */ /* number of bytes for female frequencies */ size_t geno = data->age_dep_data->geno; size_t genosize = geno * sizeof (double); /* female frequencies are equal to male frequencies at birth (before selection) */ double ffreqs[geno]; if (ffreqs == NULL) error (ENOMEM, ENOMEM, nullmsg, __LINE__); /* do not set! Use memcpy (we need to alter male frequencies (selection) without altering female frequencies) */ memmove (ffreqs, data->freqs->freqs[0], genosize); /* for (int i = 0; i < geno; i++) */ /* ffreqs[i] = data->freqs->freqs[0][i]; */ #ifdef PRMTABLE age_dep_pr_mfreqs (data); #endif /* PRMTABLE */ /* natural selection: */ age_dep_ns (data); /* normalized mating table with new frequencies */ age_dep_norm_mtable (ffreqs, data); #ifdef PRMTABLE age_dep_pr_mtable (data); #endif /* PRMTABLE */ double * newfreqs; /* mutate here */ /* i.e. get the new frequency of 0-year-olds using recombination; */ newfreqs = rec_mating (data->age_dep_data); /* return block */ { if (sim_stop_ck (data->freqs->freqs[0], newfreqs, GENO, TOL) == 0) { /* if we have converged, stop the iterations and handle the data */ age_dep_sim_out (data, stdout); return 0; } else if (tries > MAXTRIES) return ERANGE; else { /* advance generations */ for (int j = age_max - 1; j < 0; j--) memmove (data->freqs->freqs[j], data->freqs->freqs[j-1], genosize); /* advance the first age-class */ memmove (data->freqs->freqs[0], newfreqs, genosize); return 1; } } } void age_dep_ns (age_dep_params_t * data) { /* calculate the new frequency of genotypes given additive fitness and selection coefficient s */ size_t geno = data->age_dep_data->geno; double w[geno]; double wbar, dtheta, ttheta, dcond, tcond; double t, cond; /* fitness parameters */ double mu, nu; mu = data->wparams[0]; nu = data->wparams[1]; /* calculate fitness */ for (int j = 0; j < age_max; j++) { int i; for (i = 0; i < geno; i++) { /* calculate male trait: */ t = age_dep_trait(j, i, data->by); /* calculate condition: */ cond = (double) bits_popcount (bits_extract(0, CLOCI, i)); /* trait-based fitness term */ dtheta = data->theta - t; ttheta = (dtheta * dtheta) / (2.0 * nu * nu); /* condition-based fitness term */ dcond = CLOCI - cond; tcond = (dcond * dcond) / (2.0 * mu * mu); /* calculate male fitness */ w[i] = 1 + exp(-tcond) - exp(-ttheta); } /* calculate mean fitness */ /* as long as we calculate wbar before altering any values of freqs[], we're safe */ wbar = gen_mean (data->freqs->freqs[j], w, geno); for (i = 0; i < geno; i++) data->freqs->freqs[j][i] = (data->freqs->freqs[j][i] * w[i]) / wbar; } } void age_dep_norm_mtable (double * ffreqs, age_dep_params_t * params) { /* this function produces a single mating table that forms the input for recombination () */ /* i is female genotype; j is male genotype; k is male age */ int i,j,k; double norm_denom; double trait; size_t geno = params->age_dep_data->geno; for (i = 0; i < geno; i++) { double norm_mtable[geno]; /* initialize the denominator: */ norm_denom = 0.0; /* find the probability of mating and add it to the denominator */ for (j = 0; j < geno; j++) { /* initialize entry: */ norm_mtable[j] = 0.0; for (k = 0; k < age_max; k++) { trait = age_dep_trait (k, j, params->by); norm_mtable[j] += age_dep_pmate (trait, i, params->bp, params->ba) * (params->freqs->freqs)[k][j]; } norm_denom += norm_mtable[j]; } /* now calculate entry (i,j) */ for (j = 0; j < geno; j++) params->age_dep_data->mtable[i][j] = (ffreqs[i] * norm_mtable[j]) / norm_denom; } } My current suspicion is the array newfreqs: I can't memmove, memcpy or assign a stack variable then hope it will persist, can I? rec_mating() returns double *.

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  • C++: how to truncate the double in efficient way?

    - by Arman
    Hello, I would like to truncate the float to 4 digits. Are there some efficient way to do that? My current solution is: double roundDBL(double d,unsigned int p=4) { unsigned int fac=pow(10,p); double facinv=1.0/static_cast<double>(fac); double x=static_cast<unsigned int>(x*fac)/facinv; return x; } but using pow and delete seems to me not so efficient. kind regards Arman.

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  • How do I make a class whose interface matches double, but upon which templates can be specialized?

    - by Neil G
    How do I make a class whose interface matches double, but whose templated types do not dynamic cast to double? The reason is that I have a run-time type system, and I want to be able to have a type that works just like double: template<int min_value, int max_value> class BoundedDouble: public double {}; And then inherit use template specialization to get run-time information about that type: template<typename T> class Type { etc. } template<int min_value, int max_value> class Type<BoundedDouble<min_value, max_value>> { int min() const { return min_value; } etc. } But, you can't inherit from double...

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  • std::binary_function - no match for call?

    - by Venkat Shiva
    Hi, this is my code: #include <iostream> #include <functional> using namespace std; int main() { binary_function<double, double, double> operations[] = { plus<double>(), minus<double>(), multiplies<double>(), divides<double>() }; double a, b; int choice; cout << "Enter two numbers" << endl; cin >> a >> b; cout << "Enter opcode: 0-Add 1-Subtract 2-Multiply 3-Divide" << endl; cin >> choice; cout << operations[choice](a, b) << endl; } and the error I am getting is: Calcy.cpp: In function ‘int main()’: Calcy.cpp:17: error: no match for call to ‘(std::binary_function<double, double, double>) (double&, double&)’ Can anyone explain why I am getting this error and how to get rid of it?

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  • How to write Java-like enums in C++ ?

    - by Rahul G
    Coming from Java background, I find C++'s enums very lame. I wanted to know how to write Java-like enums (the ones in which the enum values are objects, and can have attributes and methods) in C++. As an example, translate the following Java code (a part of it, sufficient to demonstrate the technique) to C++ : public enum Planet { MERCURY (3.303e+23, 2.4397e6), VENUS (4.869e+24, 6.0518e6), EARTH (5.976e+24, 6.37814e6), MARS (6.421e+23, 3.3972e6), JUPITER (1.9e+27, 7.1492e7), SATURN (5.688e+26, 6.0268e7), URANUS (8.686e+25, 2.5559e7), NEPTUNE (1.024e+26, 2.4746e7); private final double mass; // in kilograms private final double radius; // in meters Planet(double mass, double radius) { this.mass = mass; this.radius = radius; } private double mass() { return mass; } private double radius() { return radius; } // universal gravitational constant (m3 kg-1 s-2) public static final double G = 6.67300E-11; double surfaceGravity() { return G * mass / (radius * radius); } double surfaceWeight(double otherMass) { return otherMass * surfaceGravity(); } public static void main(String[] args) { if (args.length != 1) { System.err.println("Usage: java Planet <earth_weight>"); System.exit(-1); } double earthWeight = Double.parseDouble(args[0]); double mass = earthWeight/EARTH.surfaceGravity(); for (Planet p : Planet.values()) System.out.printf("Your weight on %s is %f%n", p, p.surfaceWeight(mass)); } } Any hep would be greatly appreciated! Thanks!

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  • Inheritance and choose constructor from base class

    - by myle
    My question is rather simple, but I am stuck. How can I choose the desired constructor from base class? // node.h #ifndef NODE_H #define NODE_H #include <vector> // definition of an exception-class class WrongBoundsException { }; class Node { public: ... Node(double, double, std::vector<double>&) throw (WrongBoundsException); ... }; #endif // InternalNode.h #ifndef INTERNALNODE_H #define INTERNALNODE_H #include <vector> #include "Node.h" class InternalNode : public Node { public: // the position of the leftmost child (child left) int left_child; // the position of the parent int parent; InternalNode(double, double, std::vector<double>&, int parent, int left_child) throw (WrongBoundsException); private: int abcd; }; #endif // InternalNode.cpp #include "InternalNode.h" #define UNDEFINED_CHILD -1 #define ROOT -1 // Here is the problem InternalNode::InternalNode(double a, double b, std::vector<double> &v, int par, int lc) throw (WrongBoundsException) : Node(a, b, v), parent(par), left_child(lc) { std::cout << par << std::endl; } I get: $ g++ InternalNode.cpp InternalNode.cpp:16: error: declaration of ‘InternalNode::InternalNode(double, double, std::vector &, int, int) throw (WrongBoundsException)’ throws different exceptions InternalNode.h:17: error: from previous declaration ‘InternalNode::InternalNode(double, double, std::vector &, int, int)’ UPDATE 0: Fixed missing : UPDATE 1: Fixed throw exception

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  • encodingStyle usage in XmlSerializer.Serialize

    - by Vishal Seth
    Can somebody please explain the use of 4th parameter of public void Serialize( XmlWriter xmlWriter, Object o, XmlSerializerNamespaces namespaces, string encodingStyle ) My issue is this: I've following string in one of the fields of my object: "reviewed ?" // music notation When I serialize it, it becomes & # x E; // see it as one word, w/o spaces it won't let me type And it fails when I try to transform this .NET generated XML through another XSL file Is it happening because its serializing using UTF-16? Is there any way I can make it transform using UTF-8 and make this "error" go away? **

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  • How can I use the Boost Graph Library to lay out verticies?

    - by Mike
    I'm trying to lay out vertices using the Boost Graph Library. However, I'm running into some compilation issues which I'm unsure about. Am I using the BGL in an improper manner? My code is: PositionVec position_vec(2); PositionMap position(position_vec.begin(), get(vertex_index, g)); int iterations = 100; double width = 100.0; double height = 100.0; minstd_rand gen; rectangle_topology<> topology(gen, 0, 0, 100, 100); fruchterman_reingold_force_directed_layout(g, position, topology); //Compile fails on this line The diagnostics produced by clang++(I've also tried GCC) are: In file included from test.cpp:2: /Volumes/Data/mike/Downloads/boost_1_43_0/boost/graph/fruchterman_reingold.hpp:95:3: error: no member named 'dimensions' in 'boost::simple_point<double>' BOOST_STATIC_ASSERT (Point::dimensions == 2); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ In file included from test.cpp:2: In file included from /Volumes/Data/mike/Downloads/boost_1_43_0/boost/graph/fruchterman_reingold.hpp:13: In file included from /Volumes/Data/mike/Downloads/boost_1_43_0/boost/graph/graph_traits.hpp:15: In file included from /Volumes/Data/mike/Downloads/boost_1_43_0/boost/tuple/tuple.hpp:24: /Volumes/Data/mike/Downloads/boost_1_43_0/boost/static_assert.hpp:118:49: note: instantiated from: sizeof(::boost::STATIC_ASSERTION_FAILURE< BOOST_STATIC_ASSERT_BOOL_CAST( B ) >)>\ ^ In file included from test.cpp:2: /Volumes/Data/mike/Downloads/boost_1_43_0/boost/graph/fruchterman_reingold.hpp:95:3: note: instantiated from: BOOST_STATIC_ASSERT (Point::dimensions == 2); ^ ~~~~~~~ /Volumes/Data/mike/Downloads/boost_1_43_0/boost/graph/fruchterman_reingold.hpp:95:31: note: instantiated from: BOOST_STATIC_ASSERT (Point::dimensions == 2); ~~~~~~~^ /Volumes/Data/mike/Downloads/boost_1_43_0/boost/graph/fruchterman_reingold.hpp:417:19: note: in instantiation of template class 'boost::grid_force_pairs<boost::rectangle_topology<boost::random::linear_congruential<int, 48271, 0, 2147483647, 399268537> >, boost::iterator_property_map<__gnu_cxx::__normal_iterator<boost::simple_point<double> *, std::vector<boost::simple_point<double>, std::allocator<boost::simple_point<double> > > >, boost::vec_adj_list_vertex_id_map<boost::property<boost::vertex_name_t, std::basic_string<char>, boost::no_property>, unsigned long>, boost::simple_point<double>, boost::simple_point<double> &> >' requested here make_grid_force_pairs(topology, position, g)), ^ /Volumes/Data/mike/Downloads/boost_1_43_0/boost/graph/fruchterman_reingold.hpp:431:3: note: in instantiation of function template specialization 'boost::fruchterman_reingold_force_directed_layout<boost::rectangle_topology<boost::random::linear_congruential<int, 48271, 0, 2147483647, 399268537> >, boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, boost::property<boost::vertex_name_t, std::basic_string<char>, boost::no_property>, boost::no_property, boost::no_property, boost::listS>, boost::iterator_property_map<__gnu_cxx::__normal_iterator<boost::simple_point<double> *, std::vector<boost::simple_point<double>, std::allocator<boost::simple_point<double> > > >, boost::vec_adj_list_vertex_id_map<boost::property<boost::vertex_name_t, std::basic_string<char>, boost::no_property>, unsigned long>, boost::simple_point<double>, boost::simple_point<double> &>, boost::square_distance_attractive_force, boost::attractive_force_t, boost::no_property>' requested here fruchterman_reingold_force_directed_layout ^ test.cpp:48:3: note: in instantiation of function template specialization 'boost::fruchterman_reingold_force_directed_layout<boost::rectangle_topology<boost::random::linear_congruential<int, 48271, 0, 2147483647, 399268537> >, boost::adjacency_list<boost::listS, boost::vecS, boost::undirectedS, boost::property<boost::vertex_name_t, std::basic_string<char>, boost::no_property>, boost::no_property, boost::no_property, boost::listS>, boost::iterator_property_map<__gnu_cxx::__normal_iterator<boost::simple_point<double> *, std::vector<boost::simple_point<double>, std::allocator<boost::simple_point<double> > > >, boost::vec_adj_list_vertex_id_map<boost::property<boost::vertex_name_t, std::basic_string<char>, boost::no_property>, unsigned long>, boost::simple_point<double>, boost::simple_point<double> &> >' requested here fruchterman_reingold_force_directed_layout(g, position, topology); ^ 1 error generated.

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