text: iam looking for a way to Round up AND down to the nearerst 5 and then find a great common denominator of the two numbers. I need it for the caption of a y-skale on a chart.
  This is my code so far:
  function toN5( x ) { var i = 1; while( x >= 100 ) { x/=10; i*=10; } var remainder = x % 5; var distance_to_5 = (5 - remainder) % 5; return (x + distance_to_5) * i; }
  The target is something like this: The maximal value (round up to the nearest 5)
  1379.8 -> 1500
  And the other way round - minimal value (round down to the nearest 5)
  41.8 -> 0
  Then i want to find a common denominator like 250 or 500
  0 -> 250 -> 500 -> 750 -> 1000 -> 1250 -> 1500
  or:
  0 -> 500 -> 1000 -> 1500
  Is ther a way to do something like that? Thanks a lot
  If you wanted to round x to the nearest 500, you could divide it by 500, round it to the nearest integer, then multiply it by 500 again:
  x_rounded = 500 * Math.round(x/500);
  To round it to the nearest y, replace 500 with y:
  x_rounded = 250 * Math.round(x/250);
  Hopefully my maths is correct but here are various ways of "rounding"
  function sigfig(n, sf) { sf = sf - Math.floor(Math.log(n) / Math.LN10) - 1; sf = Math.pow(10, sf); n = Math.round(n * sf); n = n / sf; return n; } function precision(n, dp) { dp = Math.pow(10, dp); n = n * dp; n = Math.round(n); n = n / dp; return n; } function nearest(n, v) { n = n / v; n = Math.round(n) * v; return n; }