C++ examples for Function:Function Return
Returning a pointer from a Function
#include <iostream> #include <iomanip> #include <string> using std::string; void show_data(const double data[], int count = 1, const string& title = "Data Values", int width = 10, int perLine = 5); const double* largest(const double data[], int count); const double* smallest(const double data[], int count); double* shift_range(double data[], int count, double delta); double* scale_range(double data[], int count, double divisor); double* normalize_range(double data[], int count); int main() {/*from www. j av a 2 s . c om*/ double samples[] { 1.0, 3.0, 6.0, 4.0, 7.0, 6.0, 7.0, 8.0, 9.0, 10.0,21.0, 12.0 }; const int count{sizeof (samples) / sizeof (samples[0])}; // Number of samples show_data(samples, count, "Original Values"); // Output original values normalize_range(samples, count); // Normalize the values show_data(samples, count, "Normalized Values", 12); // Output normalized values } // Finds the largest of an array of double values const double* largest(const double data[], int count) { int index_max {}; for (int i {1} ; i < count ; ++i) if (data[index_max] < data[i]) index_max = i; return &data[index_max]; } // Finds the smallest of an array of double values const double* smallest(const double data[], int count) { int index_min{}; for (int i {1} ; i < count ; ++i) if (data[index_min] > data[i]) index_min = i; return &data[index_min]; } // Modify a range of value by delta double* shift_range(double data[], int count, double delta) { for (int i {} ; i < count ; ++i) data[i] += delta; return data; } // Scale an array of values by divisor double* scale_range(double data[], int count, double divisor) { if (!divisor) return data; // Do nothing for a zero divisor for (int i {} ; i < count ; ++i) data[i] /=divisor; return data; } // Normalize an array of values to the range 0 to 1 double* normalize_range(double data[], int count) { return scale_range(shift_range(data, count, -(*smallest(data, count))), count, *largest(data, count)); } // Outputs an array of double values void show_data(const double data[], int count, const string& title, int width, int perLine) { std::cout << title << std::endl; // Display the title // Output the data values for (int i {} ; i < count ; ++i) { std::cout << std::setw(width) << data[i]; // Display a data item if ((i + 1) % perLine == 0) // Newline after perline values std::cout << std::endl; } std::cout << std::endl; }