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    Metadata details:
    filename: test_bug1637.m
    path of file: ./repos/fieldtrip/test
    
    the code of the file until where you have to start completion: function test_bug1637

% MEM 1gb
% WALLTIME 00:10:00
% DEPENDENCY megplanar_sincos channelconnectivity ft_prepare_neighbours ft_channelselection
% DATA private

% this function checks whether megplanar_sincos relies on a fixed channel
% order or whether this can be totally mixed up (it should be able to deal
% with that!)
%
% http://bugzilla.fieldtriptoolbox.org/show_bug.cgi?id=1637

% load neighbours
cfg = [];
cfg.method = 'template';
cfg.template = 'CTF275_neighb';
neighbours = ft_prepare_neighbours(cfg);

cd(dccnpath('/home/common/matlab/fieldtrip/data/test'))
load bug1637_hdr.mat
load bug1637_grad.mat

d = pwd;
ftPath = fileparts(mfilename('fullpath')); % get path, strip away 'ft_defaults'
ftPath = strrep(ftPath, '\', '\\');

cd(fullfile(ftPath, '..', 'private'));
errored = false;
try
  cfg = [];
  cfg.neighbours = neighbours;
  cfg.channel    = ft_channelselection('MEG', hdr.label);
  [neighbsel] = match_str({cfg.neighbours.label}, cfg.channel);
  cfg.neighbours = cfg.neighbours(neighbsel);
  cfg.neighbsel = channelconnectivity(cfg);
  
  montage_other = megplanar_sincos(cfg, hdr.grad);
  

    
function test_bug1637

% MEM 1gb
% WALLTIME 00:10:00
% DEPENDENCY megplanar_sincos channelconnectivity ft_prepare_neighbours ft_channelselection
% DATA private

% this function checks whether megplanar_sincos relies on a fixed channel
% order or whether this can be totally mixed up (it should be able to deal
% with that!)
%
% http://bugzilla.fieldtriptoolbox.org/show_bug.cgi?id=1637

% load neighbours
cfg = [];
cfg.method = 'template';
cfg.template = 'CTF275_neighb';
neighbours = ft_prepare_neighbours(cfg);

cd(dccnpath('/home/common/matlab/fieldtrip/data/test'))
load bug1637_hdr.mat
load bug1637_grad.mat

d = pwd;
ftPath = fileparts(mfilename('fullpath')); % get path, strip away 'ft_defaults'
ftPath = strrep(ftPath, '\', '\\');

cd(fullfile(ftPath, '..', 'private'));
errored = false;
try
  cfg = [];
  cfg.neighbours = neighbours;
  cfg.channel    = ft_channelselection('MEG', hdr.label);
  [neighbsel] = match_str({cfg.neighbours.label}, cfg.channel);
  cfg.neighbours = cfg.neighbours(neighbsel);
  cfg.neighbsel = channelconnectivity(cfg);
  
  montage_other = megplanar_sincos(cfg, hdr.grad);
  
  montage = [];
  montage{1} = megplanar_sincos(cfg, grad);
  
  [sel12, sel22] = match_str(montage{1}.labelold, montage_other.labelold);
  [sel11, sel21] = match_str(montage{1}.labelnew, montage_other.labelnew);
  if ~isequal(montage{1}.tra(sel11, sel12), montage_other.tra(sel21, sel22))
    warning('tra matrix differs - but that''s because the montage_other.tra consists of nans - checking whether nonzero elements are the same')
    idx1 = montage{1}.tra(sel11, sel12)~=0;
    idx2 = montage_other.tra(sel21, sel22)~=0;
    if ~isequal(idx1, idx2)
      errored = true;
      error('tra matrix qualitatively differ!');
    else
      disp('...passed!')
    end