Precision of values > 53 bits
On 13-01-10 6:01 AM, Stephan Mueller wrote:
Hi, I am working with large numbers and identified that R looses precision for such high numbers. The precision is lost exactly when the number is equal or larger than 53 bits. See the following output which shows that the numbers below 53 bit have proper precision:
2^53
[1] 9007199254740992
2^53-1
[1] 9007199254740991
2^53-2
[1] 9007199254740990 Now, see the numbers above 53 bit:
2^53
[1] 9007199254740992
2^53+1
[1] 9007199254740992
2^53+2
[1] 9007199254740994
2^53+3
[1] 9007199254740996
2^53+4
[1] 9007199254740996 Is there a solution to the problem?
R has no native numeric type with more than 53 bit precision, but other packages have added it. For example, the gmp package provides an interface to the gmp library which supports arbitrarily large integers and arbitary precision rationals. Duncan Murdoch