How do I perform Array Indexing in R Language?

I am new to the R language, so I just want to know how array indexing is done in R. I mean like sorting or any calculati开发者_开发知识库ons that involve 2D arrays.

It depends,

To index elements use square brackets: ar[1], or ar[1,1] for 2d. Whole columns and rows are: ar[,1] or ar[1,]

For sorting, look at the sort and order functions.

For calculations using 2d arrays, you can have:

Elementwise: ar1+ar2, ar1*ar2

Inner product: ar1%*%ar2

Outer product: outer(ar1,ar2) or ar1%o%ar2

You must take care that the dimensions of the arrays are correct for what you want to do, though R will automatically try to recycle elements to complete a calculation.

One thing to note is that indexing is 1-based, not 0-based as in most languages, ie the first element is ar[1].