» Example how to convert a double value in a binary coded decimal

#ifndef BCD_H_INCLUDED
#define BCD_H_INCLUDED
#include <iostream>
#include <sstream>

using namespace std;


long double atold(std::string zawo)
{
 long double rewer = 0;
 std::istringstream b(zawo);
 b >> rewer;
 return rewer;
}

long double bcd(long double letter, int stellen = 0)
{
char binzahl[200];
int slei, sleib, dummy, nullsteller = 0;
long double testwert, rewer = -1;

 if ((letter >= 0) && (letter <= 4294967296) && (stellen <= 8))
  {
  rewer =  0;
  stellen *= -1;

 // Ininitalises the test value
 for (slei = 0; slei <= 99; slei++)
  binzahl[slei] = '\0';

  //testwert = 8589934592.00000;
  testwert = 1;
  for (slei = 0; slei <= 32; slei++)
  testwert *= 2;

   
 sleib = 0;

 for (slei = 32; slei >= stellen; slei--)
  {
   testwert /= 2;
   dummy = (letter / testwert);
   if (dummy != 0)
    {
     nullsteller = 1;
     binzahl[sleib] = '1';
     letter -= testwert;
    }

   if (nullsteller != 0)
   {
    if (dummy == 0)
     binzahl[sleib]= '0';
   if ((slei == 0) && (stellen < 0))
     binzahl[++sleib]= '.';
    sleib++;
   }
  }

 rewer = 0;
 std::istringstream b(binzahl);
 b >> rewer;
// only need to see if it works properly
//cout << "\nBinzahl: " << binzahl;
//cout << endl << "Ergebnis: " << fixed << rewer;
  }
return rewer;
}


#endif // BCD_H_INCLUDED

// Prototype: bcd bcd(int x);
// bcd bcd(long double x, int decimals);
// Description
// The bcd function converts x to a BCD (binary coded decimal) value.
// The x argument can be a long double value. For a long double value,
// the decimals argument, which is optional, specifies the number of digits desired after decimal 
// Return Value:   The converted value.

#include <iostream>
#include "bcd.h"

using namespace std;

int main()
{
 long double dezimalwert = 0;
 long double bcdval;
 int stellen = 3;
 cout << "Enter decimal integer Value(0 up to 4294967296): ";
 cin >> dezimalwert;
 cout << endl << "Number of decimals after point(up to 6): ";
 cin >> stellen;

 bcdval = bcd(dezimalwert, stellen);
 cout.precision(stellen);
 cout << "\nbcdval  : " << fixed << bcdval;
 return 0;
}

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