nident.m

来自「多维数据处理：MATLAB源程序用于处理多维数据」· M 代码 · 共 22 行

function id = nident(J,order,mag);

% $ Version 1.02 $ Date 28. July 1998 $ Not compiled $
%
% Make identity array of order given by "order" and dimension J.
% id = nident(J,order);
% if extra input vector, mag, is given the j'th superdiagonal will be
% equal to mag(j)

if nargin<3
  mag=ones(J,1);
end

id=zeros(J^order,1);
for f=1:J
  idd=f;
  for i=2:order
    idd=idd+J^(i-1)*(f-1);
  end
  id(idd)=mag(f);
end
id=nshape(id',[1 ones(1,order)*J],2);