Can someone please enlighten me as to why the following happens? > -2.7^8.6 [1] -5125.407 > p<- -2.7 > q<- 8.6 > p^q [1] NaN R seems perfectly able to calculate -2.7^8.6, but fails when the exact same values are assigned to variables and then the computation is repeated. Thanks in advance for any suggetsions. Kris.