% -*- texinfo -*- % @deftypefn {Function File} {@var{s} =} spalloc (@var{r}, @var{c}, @var{nz}) % Returns an empty sparse matrix of size @var{r}-by-@var{c}. As Octave % resizes sparse matrices at the first opportunity, so that no additional % space is needed, the argument @var{nz} is ignored. This function is % provided only for compatibility reasons. % % It should be noted that this means that code like % % @example % @group % k = 5; % nz = r * k; % s = spalloc (r, c, nz) % for j = 1:c % idx = randperm (r); % s (:, j) = [zeros(r - k, 1); rand(k, 1)] (idx); % end % @end group % @end example % % will reallocate memory at each step. It is therefore vitally important % that code like this is vectorized as much as possible. % @seealso{sparse, nzmax} % @end deftypefn

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