How do I obtain the machine epsilon in R?

xiaodai picture xiaodai · Apr 12, 2010 · Viewed 20.9k times · Source

Is there a constant that stores the machine epsilon in R?

Answer

Dirk Eddelbuettel picture Dirk Eddelbuettel · Apr 12, 2010

Try .Machine$double.eps -- and .Machine which on my 32-bit Linux machine yields this:

R> .Machine
$double.eps
[1] 2.220e-16

$double.neg.eps
[1] 1.110e-16

$double.xmin
[1] 2.225e-308

$double.xmax
[1] 1.798e+308

$double.base
[1] 2

$double.digits
[1] 53

$double.rounding
[1] 5

$double.guard
[1] 0

$double.ulp.digits
[1] -52

$double.neg.ulp.digits
[1] -53

$double.exponent
[1] 11

$double.min.exp
[1] -1022

$double.max.exp
[1] 1024

$integer.max
[1] 2147483647

$sizeof.long
[1] 4

$sizeof.longlong
[1] 8

$sizeof.longdouble
[1] 12

$sizeof.pointer
[1] 4

R>