You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: VBA_spm_logdet.m
    path of file: ./repos/VBA-toolbox/thrid-party/spm
    
    the code of the file until where you have to start completion: function H = VBA_spm_logdet(C)
% returns the log of the determinant of positive (semi-)definite matrix C
% FORMAT H = spm_logdet(C)
% H = log(det(C))
%
% spm_logdet is a computationally efficient operator that can deal with

    
function H = VBA_spm_logdet(C)
% returns the log of the determinant of positive (semi-)definite matrix C
% FORMAT H = spm_logdet(C)
% H = log(det(C))
%
% spm_logdet is a computationally efficient operator that can deal with
% full or sparse matrices. For non-positive definite cases, the determinant
% is considered to be the product of the positive singular values.
%__________________________________________________________________________
% Copyright (C) 2008-2011 Wellcome Trust Centre for Neuroimaging

% Karl Friston and Ged Ridgway
% $Id: spm_logdet.m 4509 2011-10-04 16:44:54Z guillaume $

% Note that whether sparse or full, rank deficient cases are handled in the
% same way as in spm_logdet revision 4068, using svd on a full version of C

[i j s] = find(C);
if any(isnan(s)), H = nan; return; end