Programme C++, sortie

Question

Il s'agit d'un programme que j'ai dû écrire pour ma classe C++, il n'y a pas de problème sauf que ma sortie affiche seulement 1 décimale et j'en ai besoin pour afficher deux (ex: 2.22, pas 2.2). Est-ce que l'un d'entre vous a une idée de comment je pourrais formater ceci pour faire ce changement?

// Author:  
// Assignment: 7 

#include <iostream> 
#include <fstream> // I/O 
#include <iomanip> // For setw() 
using namespace std; 

ofstream  outputfile("output.txt");  // Output file 

const int MAX_FILE_NAME = 35;   // Max space allocated for file name 
const double INTEREST_RATE1 = 0.015; 
const double INTEREST_RATE2 = 0.010; 
const double LEVEL_ONE_BALANCE = 1000.00; 
const double MINIMUM_PAYMENT = 10.00; 
const double MINIMUM_PAYMENT_PERCENT = 0.10; 

class Account 
{ 
public: 
Account(double Balance, double InterestRate1, double InterestRate2); 
Account(); 
double Payment(); 
double InterestDue(); 
double TotalAmountDue(); 
void output(ostream &out); // Print values on output stream out(); 

private: 
double balance; 
double interest; 
double payment; 
double interest_rate1; 
double interest_rate2; 
double total_amount_due; 
}; 

// Utility Functions 
void open_input(ifstream& input, char name[]); // Get file name & Open file 
void process_file(ifstream& input);   // Read each value & process it 

int main() 
// Parameters: None 
// Returns: Zero 
// Calls:  open_input(), process_file()  
{ char again;    // Does user want to go through loop again? 
    char file_name[MAX_FILE_NAME + 1]; // Name of file to be processed 
    ifstream input_numbers;   // For working with input file 

    cout << "This program computes the interest due, total amount due,\n" 
     << "and the minimum payment for a revolving credit account.\n" << endl; 
    system("pause"); // Hold message on screen until key is pressed 

    do 
    { 
     system("cls");       // Clear screen 
     open_input(input_numbers, file_name); // Get file name & open file 
     process_file(input_numbers);    // Process values in file 
     input_numbers.close();     // Close file 

     cout << "\nDo you want to process another file (Y/N)? "; 
     cin >> again; 
     cin.ignore(256, '\n'); // Remove Enter key from keyboard buffer 

    } while (again == 'y' || again == 'Y'); 

    cout << "\nEnd of Program!" << endl; 
    outputfile << "\n\nThanks for using CreditCalculator!\f"; 
    outputfile.close(); 

    return 0; 
} // End of main() 



void open_input(ifstream& input, char name[]) //Open file, exit on error 
// Parameters: Variables for input file reference nad input file name 
    // Returns: None 
// Calls:  None 
{ int count = 0;    // Count number of tries 
    do // Continue until we get a valid file name and can open file 
    { count++; 
     if (count != 1) // Issue error message if we are trying again. 
     { cout << "\n\aInvalid file name or file does not exist. Please try again." 
       << endl; 
     } 
     cout << "\nEnter the input file name (maximum of " << MAX_FILE_NAME 
      << " characters please)\n:> "; 
     cin.get(name, MAX_FILE_NAME + 1);// Gets at most MAX_FILE_NAME characters 
     cin.ignore(256, '\n');   // Remove Enter key from keyboard buffer 
     input.clear();     // Clear all error flags, if any, from prev try 
     input.open(name,ios_base::in); // Open only if file exists 
    } while (input.fail());   // If can't open file, try again 
} // End of open_input() 

void process_file(ifstream& input) 
{ double value;    
    Account thisAccount;    
    while (input >> value)  
    { 
     thisAccount = Account(value, INTEREST_RATE1, INTEREST_RATE2); 
     thisAccount.output(cout); 
     thisAccount.output(outputfile); 
    } 
} 

// Account Class 

Account::Account(double Balance, double InterestRate1, double InterestRate2):balance(Balance),interest_rate1(InterestRate1),interest_rate2(InterestRate2),interest(0.00),payment(0.00),total_amount_due(0.00) 

    { 
balance = Balance; 
interest_rate1 = InterestRate1; 
interest_rate2 = InterestRate2; 
Payment(); 
total_amount_due = balance + interest; 
    } 

Account::Account() 
{ 
    balance = 0.00; 
} 
double Account::InterestDue() 
{ 
    return interest; 
} 
double Account::TotalAmountDue() 
{ 
    return total_amount_due; 
} 
void Account::output(ostream &out) // Print values on output stream out(); 
{ 
    out << "\n\nBalance : $" << setw(8) << balance << endl; 
    out <<  "Payment : $" << setw(8) << payment << endl; 
    out <<  "Interest : $" << setw(8) << interest << endl; 
    out <<  "Total due : $" << setw(8) << total_amount_due << endl; 

} 
double Account::Payment() 
{ 

double newbalance = 0.00; 

if (balance > LEVEL_ONE_BALANCE) 
    interest = (balance - LEVEL_ONE_BALANCE) * interest_rate2 + LEVEL_ONE_BALANCE * interest_rate1; 
else 
    interest = balance * interest_rate1; 
newbalance = balance + interest; 

payment = newbalance * MINIMUM_PAYMENT_PERCENT; 

if (newbalance < MINIMUM_PAYMENT_PERCENT) 
    payment=newbalance; 
else 
    if (payment < MINIMUM_PAYMENT) 
      payment=MINIMUM_PAYMENT; 

return payment; 
} 

Answer 1

Vous pouvez utiliser setprecision pour définir la valeur de précision décimale de votre choix.