Hi all,
I am having a bit of trouble with the array structure of R. What I want
to do is dynamically add/remove elements to an array. For example:
Let's say I have created an array:
> myArray <- array(c(3,8), dim=c(1,2))
> myArray
[,1] [,2]
[1,] 3 8
And I now want to, for example, push an element (5,6) on to this array
so it will read:
[,1] [,2]
[1,] 3 8
[2,] 5 6
And then pop the first element of the array so the array now reads:
[,1] [,2]
[1,] 5 6
How would I do this? So far I've only read how to create an array if
you know the dimensions beforehand, but I've been unable to find how to
dynamically add/remove elements to/from an array.
I've figured out how to do this with lists and vectors, but not with
arrays. For this particular structure I need to work with arrays.
Any help on how to do something like this would be much appreciated.
Thanks, Jonck
On Mon, 9 Jun 2003, Jonck van der Kogel wrote:> Hi all, > I am having a bit of trouble with the array structure of R. What I want > to do is dynamically add/remove elements to an array. For example: > Let's say I have created an array: > > myArray <- array(c(3,8), dim=c(1,2)) > > myArray > [,1] [,2] > [1,] 3 8 > > And I now want to, for example, push an element (5,6) on to this array > so it will read: > [,1] [,2] > [1,] 3 8 > [2,] 5 6 > > And then pop the first element of the array so the array now reads: > [,1] [,2] > [1,] 5 6 > > How would I do this? So far I've only read how to create an array if > you know the dimensions beforehand, but I've been unable to find how to > dynamically add/remove elements to/from an array. > > I've figured out how to do this with lists and vectors, but not with > arrays. For this particular structure I need to work with arrays. >myArray <- array(c(3,8), dim=c(1,2)) #add to the bottom myArray <- cbind(myArray, c(5,6)) # display the top myArray # remove the top myArray <- myArray[-1,] -thomas
Have you considered "rbind" to add? Also, myArray[-2,] will remove row 2 from myArray. hope this helps. spencer graves Jonck van der Kogel wrote:> Hi all, > I am having a bit of trouble with the array structure of R. What I want > to do is dynamically add/remove elements to an array. For example: > Let's say I have created an array: > > myArray <- array(c(3,8), dim=c(1,2)) > > myArray > [,1] [,2] > [1,] 3 8 > > And I now want to, for example, push an element (5,6) on to this array > so it will read: > [,1] [,2] > [1,] 3 8 > [2,] 5 6 > > And then pop the first element of the array so the array now reads: > [,1] [,2] > [1,] 5 6 > > How would I do this? So far I've only read how to create an array if you > know the dimensions beforehand, but I've been unable to find how to > dynamically add/remove elements to/from an array. > > I've figured out how to do this with lists and vectors, but not with > arrays. For this particular structure I need to work with arrays. > > Any help on how to do something like this would be much appreciated. > Thanks, Jonck > > ______________________________________________ > R-help at stat.math.ethz.ch mailing list > https://www.stat.math.ethz.ch/mailman/listinfo/r-help