84 lines
2.1 KiB
C++
84 lines
2.1 KiB
C++
#include <iostream>
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#include <fstream>
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#include <sstream>
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#include <vector>
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#include <iomanip>
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using namespace std;
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class Interpolacja
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{
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public:
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void readFromFile(string filename)
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{
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string str;
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fstream file(filename);
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if (!file)
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{
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cerr << "Nie udalo sie otworzyc pliku o nazwie: " << filename << "\n";
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exit(EXIT_FAILURE);
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}
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while (getline(file, str))
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{
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istringstream iss(str);
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if (iss >> a >> b) {
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x.push_back(a);
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y.push_back(b);
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}
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}
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h = x[1] - x[0];
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liczba_wezlow = x.size();
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file.close();
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}
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void oblicz()
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{
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tablica_roznic.assign(liczba_wezlow, vector<float>(liczba_wezlow));
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for (int i = 0; i < liczba_wezlow; i++) {
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tablica_roznic[i][0] = y[i];
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}
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for (int j = 1; j < liczba_wezlow; j++) {
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for (int i = 0; i < liczba_wezlow - j; i++) {
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tablica_roznic[i][j] = (tablica_roznic[i + 1][j - 1] - tablica_roznic[i][j - 1]);
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}
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}
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suma = tablica_roznic[0][0];
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for (int i = 1; i < liczba_wezlow; i++) {
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czynnik = tablica_roznic[0][i];
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for (int j = 0; j < i; j++) {
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czynnik *= (x[j] - x[0]);
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}
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suma += czynnik;
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}
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}
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void wyswietl_tabela()
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{
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// nagłowki
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cout << setw(5) << "i" << setw(10) << "x" << setw(10) << "y";
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for (int j = 1; j < liczba_wezlow; ++j)
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cout << setw(10) << "Δ^" + to_string(j);
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cout << endl;
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// wartości
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for (int i = 0; i < liczba_wezlow; i++) {
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cout << setw(5) << i << setw(10) << x[i];
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for (int j = 0; j < liczba_wezlow - i; j++) {
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cout << setw(10) << tablica_roznic[i][j];
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}
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cout << endl;
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}
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cout << "Interpolowany wynik: " << suma << endl;
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}
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private:
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float a, b, h, suma, czynnik;
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int liczba_wezlow;
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vector<float> x, y;
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vector<vector<float> > tablica_roznic;
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};
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