[R] Bug in "is" ?

Carl Witthoft carl at witthoft.com
Wed Sep 24 23:58:01 CEST 2008

No doubt, 7.0 is integer in math. But if people can write 7 why people 
need to write 7.0 (I do not see any reason to do this).

First off, in physics, engineering, chem, etc.  there is a well-known 
rule that 7 implies an error of +/- 0.5 while 7.0 implies an error of 
+/-0.05 .  (actually,  the preferred notation is x.yEz so that the 
physical size of the number doesn't cause a bunch of zeroes to imply 
false precision)

Next, aside from storage reasons (if you're writing machine code or 
comms packet code),  there are times when one wishes to stay in the 
integer world as opposed to the floating-point world.  There's tons of 
literature out there about binary representation of floats, 
binary-coded-decimal, and on and on.


More information about the R-help mailing list