By careful programming practices you should be able to avoid the
problem. There is no way to prevent it since the program is only
doing what you ask it to do and if you make a mistake and ask it do to
something, it is not the program's fault. One of the nice things (&
bad things) about R is that you can redefine what the object is on the
fly.
On Mon, Feb 21, 2011 at 7:50 AM, Stefano Sofia
<stefano.sofia at regione.marche.it> wrote:> Dear list users,
> if within a function I first define a matrix
> mymat <- matrix(NA, nrow=m, ncol=n)
> and somewhere afterwards by mistake
> mymat <- c(1,2,3)
> this second command deletes the first one.
> How can I make sure that within the function mymat will always remain the
matrix defined at the beginning, without possibility of changing it throughout
the code?
> Secondly, is it possible to define mymat as a matrix of integers, with no
possibility of loading real numbers?
>
> Thank you for your help
> Stefano Sofia
>
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--
Jim Holtman
Data Munger Guru
What is the problem that you are trying to solve?