Re: [R] Meaning of following function

2010-08-01 Thread Matt Shotwell
Ron, In arithmetic, '-' and '+' are binary _and_ unary operators. That is, both -1 and 1-1 are valid arithmetic expressions, the former negates its argument, and the latter subtracts the second from the first. Since much of R is designed do arithmetic, R honors the unary _and_ binary versions of '

Re: [R] Meaning of following function

2010-08-01 Thread Joshua Wiley
On Sun, Aug 1, 2010 at 7:56 AM, Ron Michael wrote: > Hi friends, I am aware of the function "-"() which acts as minus in ordinary > computations. For example: > >> "-"(3, 1) > [1] 2 > > However what is the meaning of >> "-"(3) > [1] -3 This seems quite functionally useful; consider the behavior

Re: [R] Meaning of following function

2010-08-01 Thread Nikhil Kaza
well "*"(3,2) works but "*"(3,2,3) does not. You should now be able to figure out the logic. It is related to the number of arguments that make sense. Nikhil Kaza Asst. Professor, City and Regional Planning University of North Carolina nikhil.l...@gmail.com On Aug 1, 2010, at 10:56 AM, R

[R] Meaning of following function

2010-08-01 Thread Ron Michael
Hi friends, I am aware of the function "-"() which acts as minus in ordinary computations. For example:   > "-"(3, 1) [1] 2 However what is the meaning of > "-"(3) [1] -3 I was expecting R to generate some error as it does for "*"(3). What is the logic for that calculation?   Thanks,