R, accessing a column vector of a matrix by name [duplicate]

Answer 1

The following should do it:

mat2[,'saturn']

For example:

> x <- matrix(1:21, nrow=7, ncol=3)
> colnames(x) <- paste('name', 1:3)
> x[,'name 1']
[1] 1 2 3 4 5 6 7

Answer 2

Bonus information (adding to the first answer)

x[,c('name 1','name 2')]

would return two columns just as if you had done

x[,1:2]

And finally, the same operations can be used to subset rows

x[1:2,]

And if rows were named...

x[c('row 1','row 2'),]

Note the position of the comma within the brackets and with respect to the indices.