function [rms_value]=rms(Field_in)
%agel FORGET 22/01/03
a=size(Field_in);
ndim=length(a);
n=1;
Field_tmp=Field_in.*Field_in;
for i=1:ndim
        n=n*a(i);
        Field_tmp=sum(Field_tmp,ndim-i+1);
end
rms_value=sqrt(Field_tmp/n);