The Largest factorial number in R

Question

If I run the factorial(1:200) , the largest value is 7.257416e+306 , any value above that is "Inf" .

1. Does this means the largest value inside R programming is 7.257416e+306 . We can not calculate the value above factorial(170) ?
2. But when I run the code ".Machine$double.xmax", the biggest value is 1.797693e+308 .

So, I am a bit confused, which one is the biggest value in R?

Answer 1

The largest number in base R has nothing to do with the factorial function. The likelihood that the largest number is going to coincide with a factorial is very small. The largest representable number differs depending on your computer. You can see it by running. .Machine$double.xmax . Everything above that is Inf .

You see 171*factorial(170) is simply larger than your machine's .Machine$double.xmax even though factorial(170) is smaller.

If you want larger numbers in R consider the discussion in this question