Why do errors in arithmetic calculations when passing argument in function occur?

Question

The code below compiles properly, but the calculation seems to be an issue. When printing out the first deduction 'withdraw', the customerBalance is 2.07361e (8032.78 - 244.0 = 7788.78)? The data members are private, but it didn't appear to be an issue with it being public or private. I'm not sure. Any suggestions would be welcome. Thank you.

#include <iostream>
#include "BankAccount.hpp"
using namespace std;

BankAccount::BankAccount(string name, string ID, double balance)
{
    customerName = name;
    customerID = ID;
    customerBalance = balance;

}

string BankAccount::getCustomerName()
{
    return customerName;
}

string BankAccount::getCustomerID()
{
    return customerID;
}

double BankAccount::getCustomerBalance()
{
    return customerBalance;
}

void BankAccount::withdraw(double w)
{

    customerBalance = (customerBalance - w);
}

void BankAccount::deposit(double d)
{
    customerBalance = (customerBalance + d);
}

int main()
{
    double customerBalance;

    BankAccount account1("Harry Potter", "K4637", 8032.78);
    account1.withdraw(244.0);
    cout << customerBalance;
    account1.withdraw(3012.58);
    account1.deposit(37.54);
    account1.withdraw(1807.12);
    account1.deposit(500.00);
    double finalBalance = account1.getCustomerBalance();
 }

The customerBalance that you declare in main() is not the same as the one in the class. You're basically printing an unasigned variable. — DeiDei, Apr 28 '16 at 01:45
Also, seriously, stop using `double` for currency. It's a completely unsuitable type. http://stackoverflow.com/a/3730040/327083 , http://stackoverflow.com/q/273371/327083 , http://stackoverflow.com/q/32212213/327083 , etc... — J..., Apr 28 '16 at 02:04

score 3 · Answer 1 · answered Apr 28 '16 at 01:46

3

The cusotmerBalance you've declared in main is different than BankAccount::customerBalance. You never initialize customerBalance, so it has an undefined value when you print it.

answered Apr 28 '16 at 01:46

Miles Budnek

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1

So change `cout << customerBalance;` to `cout << account1.getCustomerBalance()`. – David Schwartz Apr 28 '16 at 01:47
and take out `double customerBalance;` to avoid accidentally using it – M.M Apr 28 '16 at 02:16

Why do errors in arithmetic calculations when passing argument in function occur?

1 Answers1