/
tendiag.m
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/
tendiag.m
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function X = tendiag(v,sz)
%TENDIAG Creates a tensor with v on the diagonal.
%
% TENDIAG(V) creates a tensor with N dimensions, each of size N, where N
% is the number of elements of V. The elements of V are placed on the
% superdiagonal.
%
% TENDIAG(V,SZ) is the same as above but creates a tensor of size SZ. If
% SZ is not big enough, the tensor will be enlarged to accommodate the
% elements of V on the superdiagonal.
%
% Examples
% X = tendiag([0.1 0.22 0.333]) %<-- creates a 3x3x3 tensor
%
% See also TENSOR, SPTENDIAG.
%
%MATLAB Tensor Toolbox.
%Copyright 2015, Sandia Corporation.
% This is the MATLAB Tensor Toolbox by T. Kolda, B. Bader, and others.
% http://www.sandia.gov/~tgkolda/TensorToolbox.
% Copyright (2015) Sandia Corporation. Under the terms of Contract
% DE-AC04-94AL85000, there is a non-exclusive license for use of this
% work by or on behalf of the U.S. Government. Export of this data may
% require a license from the United States Government.
% The full license terms can be found in the file LICENSE.txt
% Make sure v is a column vector
v = reshape(v,[numel(v) 1]);
N = numel(v);
if ~exist('sz','var')
sz = repmat(N,1,N);
end
X = tenzeros(sz);
subs = repmat((1:N)', 1, length(sz));
X(subs) = v;