[R] Standard Deviation of a matrix

[Paul Hiemstra]

 Hi!

The sample below should give you what you want:

M = matrix(runif(100), 10, 10)
sd(as.numeric(M))

So the as.numeric command is the key. It transforms the matrix to a 1D
vector. Or alternatively without using as.numeric:

M = matrix(runif(100), 10, 10)
M
dim(M) = 100
M
sd(M)

Here I use the dim command to set the dimensions to a vector of 100 long.

cheers,
Paul

On 08/02/2011 11:07 AM, chakri wrote:
> Hello,
>
> My R knowledge could not take me any further, so this request !
>
> I have a matrix of dimensions (1185 X 1185). I want to calculate standard
> deviation of entire matrix. 
> sd function of {stats} calculates standard deviation for each row/column,
> giving 1 X 1185 matrix as result. I would like to have 1 X 1 matrix as
> result.
>
> Any ideas, how to do this ?
>
> TIA
> Chakri 
>
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-- 
Paul Hiemstra, Ph.D.
Global Climate Division
Royal Netherlands Meteorological Institute (KNMI)
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