printing answer up to 9 digits on division in java

Question

How do we print division up to 9 digits?

If variable num holds 2 and variable den holds 4, then I need to print 0.500000000

double ans=(double)(num)/(double)(den);
System.out.println(ans);

Answer 1

Use String.format:

System.out.println(String.format("%.9f", ans));

Like in C, the %f tell the format to expect a float/double value, and the .9 instructs it to print 9 digits after the decimal point.