inconsistent rounding

[Anon]

I've noticed that sometimes PHP rounds a .5 up and sometimes down, using both the number_format and printf functions. For instance, in a page I just made with a list of numbers, 81.945 gets rounded up to 81.95, while 101.565 gets rounded down to 101.56. Does anyone know why this happens, or a way to make the built in functions consistent? Thanks much.

[[deleted]]

Which version of PHP are you using?
Neither number_format nor printf should actually round the numbers at all, they just print them, they shouldn't change the value itself.
Only functions like round() should change the value.

[Anon]

I'm sorry - I didn't mean it actually changed the value. I was having trouble with the value it was printing to the browser. The issue was that I wasn't viewing enough decimal places of the number. So what I thought was a .5 being rounded down was really a .49999999999999. I had thought I was viewing all the decimal places, but I was not. By the way, I am using PHP 4.04 for Mac OS X. Thanks for your help.