I am trying to compute a summation of float numbers. All small numbers output properly, when I use very large numbers as inputs, the output is always off by a few integers. For example, H = 5764801 W = 1679616, on paper, works out as 335923 30275911. In my program though, 335923 30275908 is printed instead. Here is the code:
public void printOutput(int H, int W) // The inputs
{
if(H == 1 && W == 1)
{
System.out.println(0 + " " + 1);
return;
}
List<Integer> pfw = primeFactors(W);
int y = 1;
while(H != (int) (Math.pow(Math.pow(W, 1f/y) + 1f, y))) y++;
final float N = findWholeNumber(pfw);
float height = 0;
for(int x = 1; x <= y + 1; x++)
{
height += (float) (W * Math.pow((N + 1f) / N, x-1f) + 1e-8); //Here is the summation
}
float cats = 1;
for(int x = 2; x <= y + 1; x++)
cats += (float) (Math.pow(N, x-1));
int notWorking = (int) (cats - W);
System.out.println(notWorking + " " + (int)height); //Outputs printing
}
private int findWholeNumber(List<Integer> factors)
{
List<Integer> common = new ArrayList<Integer>();
for(int i = 0; i < factors.size(); i++)
{
if(common.contains(factors.get(i))) continue;
common.add(factors.get(i));
}
int num = common.get(0);
for(int i = 1; i < common.size(); i++)
num *= common.get(i);
return num;
}
private List<Integer> primeFactors(int num)
{
List<Integer> pf = new ArrayList<Integer>();
if(num == 1)
{
pf.add(1);
return pf;
}
for(int j = 2; j <= num; j++)
while(num % j == 0) // is prime
{
pf.add(j);
num /= j;
}
return pf;
}
}
double
?