读取Matrix txt文件并存储为数组

我目前正在编写模拟退火代码来解决旅行商问题,并且在存储和使用来自txt文件的读取数据时遇到了困难.文件中的每一行和每列代表每个城市,两个不同城市之间的距离存储为15 x 15矩阵:

0.0 5.0 5.0 6.0 7.0 2.0 5.0 2.0 1.0 5.0 5.0 1.0 2.0 7.1 5.0
5.0 0.0 5.0 5.0 5.0 2.0 5.0 1.0 5.0 6.0 6.0 6.0 6.0 1.0 7.1
5.0 5.0 0.0 6.0 1.0 6.0 5.0 5.0 1.0 6.0 5.0 7.0 1.0 5.0 6.0
6.0 5.0 6.0 0.0 5.0 2.0 1.0 6.0 5.0 6.0 2.0 1.0 2.0 1.0 5.0
7.0 5.0 1.0 5.0 0.0 7.0 1.0 1.0 2.0 1.0 5.0 6.0 2.0 2.0 5.0
2.0 2.0 6.0 2.0 7.0 0.0 5.0 5.0 6.0 5.0 2.0 5.0 1.0 2.0 5.0
5.0 5.0 5.0 1.0 1.0 5.0 0.0 2.0 6.0 1.0 5.0 7.0 5.0 1.0 6.0
2.0 1.0 5.0 6.0 1.0 5.0 2.0 0.0 7.0 6.0 2.0 1.0 1.0 5.0 2.0
1.0 5.0 1.0 5.0 2.0 6.0 6.0 7.0 0.0 5.0 5.0 5.0 1.0 6.0 6.0
5.0 6.0 6.0 6.0 1.0 5.0 1.0 6.0 5.0 0.0 7.0 1.0 2.0 5.0 2.0
5.0 6.0 5.0 2.0 5.0 2.0 5.0 2.0 5.0 7.0 0.0 2.0 1.0 2.0 1.0
1.0 6.0 7.0 1.0 6.0 5.0 7.0 1.0 5.0 1.0 2.0 0.0 5.0 6.0 5.0
2.0 6.0 1.0 2.0 2.0 1.0 5.0 1.0 1.0 2.0 1.0 5.0 0.0 7.0 6.0
7.0 1.0 5.0 1.0 2.0 2.0 1.0 5.0 6.0 5.0 2.0 6.0 7.0 0.0 5.0
5.0 7.0 6.0 5.0 5.0 5.0 6.0 2.0 6.0 2.0 1.0 5.0 6.0 5.0 0.0

为了阅读本文,我有一个LoadCities()函数,如下所示:

#include "iostream"
#include "fstream"      
#include "string"   
using namespace std;

double distances [15][15];  

void LoadCities()
{
    ifstream CityFile;

    if (!CityFile.is_open()) //check is file has been opened
    {
        CityFile.open ("Cities.txt", ios::in | ios::out);

        if (!CityFile)
        {
            cerr << "Failed to open " << CityFile << endl;
            exit(EXIT_FAILURE);  //abort program
        }
    }

    int length;
    char * buffer;
    string cities;

    CityFile.seekg(0, ios::end);
    length = CityFile.tellg();
    CityFile.seekg (0, ios::beg);

    buffer = new char [length];

    cities = CityFile.read (buffer,length); 

    string rows = strtok(cities, "\n");

    distances = new double[rows.length()][rows.length()];

            for (int i = 0; i < (string) rows.length(); i++)
            {
                string distance = strtok(rows[i], " ");

                for (int j = 0; j < distance.length(); j++)
                {
                    distances[i][j] = (double) Parse(distance[j]);
                }
            }

    CityFile.close();
}

我已经尝试了一种替代的istreambuf_iterator方法,以便将读取材料操作到数组中,但是我似乎总是遇到并发症:

ifstream CityFile("Cities.txt");
string theString((std::istreambuf_iterator(CityFile)), std::istreambuf_iterator());

任何帮助都会很有帮助.一直在抨击我,但收效甚微!

@ SoapBox - SA代码,函数和main()的一些细节.这不是干净,高效,整洁,并不是现阶段的工作,只需要暂时工作.此版本(下面)工作并设置为解决多项式(最简单的问题).将其转换为旅行商问题需要做的是:

编写LoadCities()函数以收集距离数据.(当前)

更改Initialise()以获取所涉及的距离总和

将E()更改为TSP函数(例如,计算随机路径的距离)

后两个我知道我可以做,但是我需要LoadCities()来做.以下脚本中无需更改任何其他内容.

#include "math.h"
#include "iostream"
#include "fstream"
#include "time.h"   // Define time()
#include "stdio.h"  // Define printf()
#include "randomc.h"    // Define classes for random number generators
#include "mersenne.cpp" // Include code for the chosen random number generator

using namespace std; // For the use of text generation in application

double T;
double T_initial;

double S;
double S_initial;
double S_current;
double S_trial;

double E_current;

int N_step;        // Number of Iterations for State Search per Temperature
int N_max;         //Number of Iterations for Temperature
int Write;

const double EXP = 2.718281828;

//------------------------------------------------------------------------------
//Problem Function of Primary Variable (Debugged 17/02/09 - Works as intended)

double E(double x) //ORIGNINAL
{
    double y = x*x - 6*x + 2;

     return y;
}

//------------------------------------------------------------------------------
//Random Number Generation Function (Mod 19/02/09 - Generated integers only & fixed sequence)

double Random_Number_Generator(double nHigh, double nLow) 
{
    int seed = (int)time(0);            // Random seed

    CRandomMersenne RanGen(seed);       // Make instance of random number generator

    double fr;                          // Random floating point number

    fr = ((RanGen.Random() * (nHigh - nLow)) + nLow);   // Generatres Random Interger between nLow & nHigh

    return fr;
}

//------------------------------------------------------------------------------
//Initializing Function (Temp 17/02/09)

void Initialize() //E.g. Getting total Distance between Cities
{
    S_initial = Random_Number_Generator(10, -10);

    cout << "S_Initial: " << S_initial << endl;
}

//------------------------------------------------------------------------------
//Cooling Schedule Function (make variables) (Completed 16/02/09)

double Schedule(double Temp, int i) // Need to find cooling schedule
{
    double CoolingRate = 0.9999;

    return Temp *= CoolingRate; 
}

//------------------------------------------------------------------------------
//Next State Function (Mod 18/02/09)

double Next_State(double T_current, int i)
{
        S_trial = Random_Number_Generator(pow(3, 0.5), pow(3, 0.5)*-1); 

        S_trial += S_current;

        double E_t = E(S_trial);
        double E_c = E(S_current);

        double deltaE = E_t - E_c;                              //Defines gradient of movement

        if ( deltaE <= 0 )                                      //Downhill
        {    
            S_current = S_trial;
            E_current = E_t;
        }
        else                                                    //Uphill
        {
            double R = Random_Number_Generator(1,0);            //pseudo random number generated
            double Ratio = 1-(float)i/(float)N_max;             //Control Parameter Convergence to 0
            double ctrl_pram = pow(EXP, (-deltaE / T_current)); //Control Parameter

            if (R < ctrl_pram*Ratio)                            //Checking 
            {   
                S_current = S_trial;                            //Expresses probability of uphill acceptance
                E_current = E_t;                                
            }
            else 
                E_current = E_c;
        }

        return S_current;
}

//------------------------------------------------------------------------------
//Metropolis Function (Mod 18/02/09)

double Metropolis(double S_start, double T_current, int N_Steps, int N_temperatures)
{
     S_current = S_start;                                       //Initialised S_initial equated to S_current

     for ( int i=1; i <= N_step; i++ )                          //Iteration of neighbour states
        S_current = Next_State(T_current, N_temperatures);      //Determines acceptance of new states

     return S_current;
}

//------------------------------------------------------------------------------
//Write Results to Notepad (Completed 18/02/09)

void WriteResults(double i, double T, double x, double y)
{
//This function opens a results file (if not already opened)
//and stores results for one time step

    static ofstream OutputFile;
    const int MAXLENGTH = 80;

    if (!OutputFile.is_open()) //check is file has been opened
    {
        //no it hasn't. Get a file name and open it.
        char FileName[MAXLENGTH];

        //read file name
        cout << "Enter file name: ";
        do
        {
            cin.getline(FileName, MAXLENGTH);
        }
        while (strlen(FileName) <= 0); //try again if length of string is 0

        //open file
        OutputFile.open(FileName);

        // check if file was opened successfully
        if (!OutputFile)
        {
            cerr << "Failed to open " << FileName << endl;
            exit(EXIT_FAILURE);  //abort program
        }

        OutputFile << "Iterations" << '\t' << "Temperatures" << '\t' << "X-Value" << '\t' << "Y-Value" << endl; 
        OutputFile << endl;
    }

    //OutputFile.width(10);
    OutputFile << i << '\t' << T << '\t' << x << '\t' << y << endl; 

    if (i == N_max) 
    {   
        OutputFile << endl
               << "Settings: " << endl
               << "Initial Temperature: " << T_initial << endl
               << "Temperature Iterations: " << N_max << endl
               << "Step Iterations: " << N_step << endl
               << endl
               << "Results: " << endl
               << "Final Temperature: " << T << endl 
               << "Minimum: " << S << endl;

        OutputFile.close();
    }
}

//------------------------------------------------------------------------------
//Main SA Function (Mod 17/02/09)

void SA(int W)
{
    S = S_initial;
    T = T_initial;

    for ( int N_temperatures = 1 ; N_temperatures <= N_max ; N_temperatures++ )
    {
        S = Metropolis( S, T, N_step, N_temperatures);
        T = Schedule(T, N_temperatures);

        if (W == 1)
            WriteResults(N_temperatures, T, S, E_current);
    }

    cout << "Result" << endl
    << "Y-value> " << S << endl
    << "Temperature> " << T << endl;

}

//------------------------------------------------------------------------------
//Execution of Traveling Salesman Problem (Progress 18/02/09)


int main()
{
    cout << "Quadratic Function" << endl
         << "Solving method: Simulated Annealing" << endl;
    cout << "" << endl;

    cout << "Select desired Initial Temperature:" << endl
         << "> ";
    cin >> T_initial;

    cout << "Select desired number of Temperature Iterations:" << endl
         << "> ";
    cin >> N_max;

    cout << "Select desired number of step Iterations:" << endl
         << "> ";
    cin >> N_step;

    Initialize();

    cout << "Write to file: (1 / 0) " << endl
         << "> ";
    cin >> Write;

    SA(Write);

    system ("PAUSE");

    return 0;
}

@ strager - 我知道它的代码很糟糕,但不幸的是,我的项目所涉及的时间限制和组合学习曲线,结果都是需要的!:)它将在后期阶段进行整理.

@dirkgently - 这是这样做的最初原因,因此我的第一次尝试就是这样做.

这个怎么样？(KISS解决方案)

void LoadCities() {
  int x, y;
  ifstream in("Cities.txt");

  if (!in) {
    cout << "Cannot open file.\n";
    return;
  }

  for (y = 0; y < 15; y++) {
    for (x = 0; x < 15; x++) {
      in >> distances[x][y];
    }
  }

  in.close();
}

适合我.可能不是那么复杂,也许不是很高效,但只要你不读1000x1000阵列,你就不会看到任何差别.