title: How to find mantissa length on a particular machine?
body: <p>I'm wanting to find the number of mantissa digits and the unit round-off on a particular computer.  I have an understanding of what these are, just no idea how to find them - though I understand they can vary from computer to computer. </p>
  
  <p>I need this number in order to perform certain aspects of numerical analysis, like analyzing errors.</p>
  
  <p>What I'm currently thinking is that I could write a small c++ program to slowly increment a number until overflow occurs, but I'm not sure what type of number to use.</p>
  
  <p>Am I on the right track? How exactly does one go about calculating this?</p>