[R] Integer precision etc.

[Simon Fear]

1e100 is just one example of much bigger number that is exactly
represented
(in floating point). But of course
> 1e100+1 - 1e100
[1] 0

You mean the biggest number such that adding one changes the result?

I should be extremely careful with

> print( 9007199254740994, digits=20)
[1] 9007199254740994
> print( 9007199254740994-1, digits=20)
[1] 9007199254740992

Here subtracting one makes a difference of two ... but the numbers look
like
integers.
 

Simon Fear
Senior Statistician
Syne qua non Ltd
Tel: +44 (0) 1379 644449
Fax: +44 (0) 1379 644445
email: Simon.Fear at synequanon.com
web: http://www.synequanon.com
 
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