Ejemplo n.º 1
0
void run()
{

  // Read filenames
  vector<std::string> filenames;
  {
    std::string folder = Path::dirname (argument[0]);
    std::ifstream ifs (argument[0].c_str());
    std::string temp;
    while (getline (ifs, temp)) {
      std::string filename (Path::join (folder, temp));
      size_t p = filename.find_last_not_of(" \t");
      if (std::string::npos != p)
        filename.erase(p+1);
      if (filename.size()) {
        if (!MR::Path::exists (filename))
          throw Exception ("Input connectome file not found: \"" + filename + "\"");
        filenames.push_back (filename);
      }
    }
  }

  const MR::Connectome::matrix_type example_connectome = load_matrix (filenames.front());
  if (example_connectome.rows() != example_connectome.cols())
    throw Exception ("Connectome of first subject is not square (" + str(example_connectome.rows()) + " x " + str(example_connectome.cols()) + ")");
  const MR::Connectome::node_t num_nodes = example_connectome.rows();

  // Initialise enhancement algorithm
  std::shared_ptr<Stats::EnhancerBase> enhancer;
  switch (int(argument[1])) {
    case 0: {
      auto opt = get_options ("threshold");
      if (!opt.size())
        throw Exception ("For NBS algorithm, -threshold option must be provided");
      enhancer.reset (new MR::Connectome::Enhance::NBS (num_nodes, opt[0][0]));
      }
      break;
    case 1: {
      std::shared_ptr<Stats::TFCE::EnhancerBase> base (new MR::Connectome::Enhance::NBS (num_nodes));
      enhancer.reset (new Stats::TFCE::Wrapper (base));
      load_tfce_parameters (*(dynamic_cast<Stats::TFCE::Wrapper*>(enhancer.get())));
      if (get_options ("threshold").size())
        WARN (std::string (argument[1]) + " is a threshold-free algorithm; -threshold option ignored");
      }
      break;
    case 2: {
      enhancer.reset (new MR::Connectome::Enhance::PassThrough());
      if (get_options ("threshold").size())
        WARN ("No enhancement algorithm being used; -threshold option ignored");
      }
      break;
    default:
      throw Exception ("Unknown enhancement algorithm");
  }

  size_t num_perms = get_option_value ("nperms", DEFAULT_NUMBER_PERMUTATIONS);
  const bool do_nonstationary_adjustment = get_options ("nonstationary").size();
  size_t nperms_nonstationary = get_option_value ("nperms_nonstationarity", DEFAULT_NUMBER_PERMUTATIONS_NONSTATIONARITY);

  // Load design matrix
  const matrix_type design = load_matrix (argument[2]);
  if (size_t(design.rows()) != filenames.size())
    throw Exception ("number of subjects does not match number of rows in design matrix");

  // Load permutations file if supplied
  auto opt = get_options("permutations");
  vector<vector<size_t> > permutations;
  if (opt.size()) {
    permutations = Math::Stats::Permutation::load_permutations_file (opt[0][0]);
    num_perms = permutations.size();
    if (permutations[0].size() != (size_t)design.rows())
      throw Exception ("number of rows in the permutations file (" + str(opt[0][0]) + ") does not match number of rows in design matrix");
  }

  // Load non-stationary correction permutations file if supplied
  opt = get_options("permutations_nonstationary");
  vector<vector<size_t> > permutations_nonstationary;
  if (opt.size()) {
    permutations_nonstationary = Math::Stats::Permutation::load_permutations_file (opt[0][0]);
    nperms_nonstationary = permutations.size();
    if (permutations_nonstationary[0].size() != (size_t)design.rows())
      throw Exception ("number of rows in the nonstationary permutations file (" + str(opt[0][0]) + ") does not match number of rows in design matrix");
  }


  // Load contrast matrix
  matrix_type contrast = load_matrix (argument[3]);
  if (contrast.cols() > design.cols())
    throw Exception ("too many contrasts for design matrix");
  contrast.conservativeResize (contrast.rows(), design.cols());

  const std::string output_prefix = argument[4];

  // Load input data
  // For compatibility with existing statistics code, symmetric matrix data is adjusted
  //   into vector form - one row per edge in the symmetric connectome. The Mat2Vec class
  //   deals with the re-ordering of matrix data into this form.
  MR::Connectome::Mat2Vec mat2vec (num_nodes);
  const size_t num_edges = mat2vec.vec_size();
  matrix_type data (num_edges, filenames.size());
  {
    ProgressBar progress ("Loading input connectome data", filenames.size());
    for (size_t subject = 0; subject < filenames.size(); subject++) {

      const std::string& path (filenames[subject]);
      MR::Connectome::matrix_type subject_data;
      try {
        subject_data = load_matrix (path);
      } catch (Exception& e) {
        throw Exception (e, "Error loading connectome data for subject #" + str(subject) + " (file \"" + path + "\"");
      }

      try {
        MR::Connectome::to_upper (subject_data);
        if (size_t(subject_data.rows()) != num_nodes)
          throw Exception ("Connectome matrix is not the correct size (" + str(subject_data.rows()) + ", should be " + str(num_nodes) + ")");
      } catch (Exception& e) {
        throw Exception (e, "Connectome for subject #" + str(subject) + " (file \"" + path + "\") invalid");
      }

      for (size_t i = 0; i != num_edges; ++i)
        data(i, subject) = subject_data (mat2vec(i).first, mat2vec(i).second);

      ++progress;
    }
  }

  {
    ProgressBar progress ("outputting beta coefficients, effect size and standard deviation...", contrast.cols() + 3);

    const matrix_type betas = Math::Stats::GLM::solve_betas (data, design);
    for (size_t i = 0; i < size_t(contrast.cols()); ++i) {
      save_matrix (mat2vec.V2M (betas.col(i)), output_prefix + "_beta_" + str(i) + ".csv");
      ++progress;
    }

    const matrix_type abs_effects = Math::Stats::GLM::abs_effect_size (data, design, contrast);
    save_matrix (mat2vec.V2M (abs_effects.col(0)), output_prefix + "_abs_effect.csv");
    ++progress;

    const matrix_type std_effects = Math::Stats::GLM::std_effect_size (data, design, contrast);
    matrix_type first_std_effect = mat2vec.V2M (std_effects.col (0));
    for (MR::Connectome::node_t i = 0; i != num_nodes; ++i) {
      for (MR::Connectome::node_t j = 0; j != num_nodes; ++j) {
        if (!std::isfinite (first_std_effect (i, j)))
          first_std_effect (i, j) = 0.0;
      }
    }
    save_matrix (first_std_effect, output_prefix + "_std_effect.csv");
    ++progress;

    const matrix_type stdevs = Math::Stats::GLM::stdev (data, design);
    save_vector (stdevs.col(0), output_prefix + "_std_dev.csv");
  }

  Math::Stats::GLMTTest glm_ttest (data, design, contrast);

  // If performing non-stationarity adjustment we need to pre-compute the empirical statistic
  vector_type empirical_statistic;
  if (do_nonstationary_adjustment) {
    empirical_statistic = vector_type::Zero (num_edges);
    if (permutations_nonstationary.size()) {
      Stats::PermTest::PermutationStack perm_stack (permutations_nonstationary, "precomputing empirical statistic for non-stationarity adjustment...");
      Stats::PermTest::precompute_empirical_stat (glm_ttest, enhancer, perm_stack, empirical_statistic);
    } else {
      Stats::PermTest::PermutationStack perm_stack (nperms_nonstationary, design.rows(), "precomputing empirical statistic for non-stationarity adjustment...", true);
      Stats::PermTest::precompute_empirical_stat (glm_ttest, enhancer, perm_stack, empirical_statistic);
    }
    save_matrix (mat2vec.V2M (empirical_statistic), output_prefix + "_empirical.csv");
  }

  // Precompute default statistic and enhanced statistic
  vector_type tvalue_output   (num_edges);
  vector_type enhanced_output (num_edges);

  Stats::PermTest::precompute_default_permutation (glm_ttest, enhancer, empirical_statistic, enhanced_output, std::shared_ptr<vector_type>(), tvalue_output);

  save_matrix (mat2vec.V2M (tvalue_output),   output_prefix + "_tvalue.csv");
  save_matrix (mat2vec.V2M (enhanced_output), output_prefix + "_enhanced.csv");

  // Perform permutation testing
  if (!get_options ("notest").size()) {

    // FIXME Getting NANs in the null distribution
    // Check: was result of pre-nulled subject data
    vector_type null_distribution (num_perms);
    vector_type uncorrected_pvalues (num_edges);

    if (permutations.size()) {
      Stats::PermTest::run_permutations (permutations, glm_ttest, enhancer, empirical_statistic,
                                         enhanced_output, std::shared_ptr<vector_type>(),
                                         null_distribution, std::shared_ptr<vector_type>(),
                                         uncorrected_pvalues, std::shared_ptr<vector_type>());
    } else {
      Stats::PermTest::run_permutations (num_perms, glm_ttest, enhancer, empirical_statistic,
                                         enhanced_output, std::shared_ptr<vector_type>(),
                                         null_distribution, std::shared_ptr<vector_type>(),
                                         uncorrected_pvalues, std::shared_ptr<vector_type>());
    }

    save_vector (null_distribution, output_prefix + "_null_dist.txt");
    vector_type pvalue_output (num_edges);
    Math::Stats::Permutation::statistic2pvalue (null_distribution, enhanced_output, pvalue_output);
    save_matrix (mat2vec.V2M (pvalue_output),       output_prefix + "_fwe_pvalue.csv");
    save_matrix (mat2vec.V2M (uncorrected_pvalues), output_prefix + "_uncorrected_pvalue.csv");

  }

}
Ejemplo n.º 2
0
void run() {

  const value_type cluster_forming_threshold = get_option_value ("threshold", NaN);
  const value_type tfce_dh = get_option_value ("tfce_dh", DEFAULT_TFCE_DH);
  const value_type tfce_H = get_option_value ("tfce_h", DEFAULT_TFCE_H);
  const value_type tfce_E = get_option_value ("tfce_e", DEFAULT_TFCE_E);
  const bool use_tfce = !std::isfinite (cluster_forming_threshold);
  int num_perms = get_option_value ("nperms", DEFAULT_NUMBER_PERMUTATIONS);
  int nperms_nonstationary = get_option_value ("nperms_nonstationary", DEFAULT_NUMBER_PERMUTATIONS_NONSTATIONARITY);

  const bool do_26_connectivity = get_options("connectivity").size();
  const bool do_nonstationary_adjustment = get_options ("nonstationary").size();

  // Read filenames
  vector<std::string> subjects;
  {
    std::string folder = Path::dirname (argument[0]);
    std::ifstream ifs (argument[0].c_str());
    std::string temp;
    while (getline (ifs, temp))
      subjects.push_back (Path::join (folder, temp));
  }

  // Load design matrix
  const matrix_type design = load_matrix<value_type> (argument[1]);
  if (design.rows() != (ssize_t)subjects.size())
    throw Exception ("number of input files does not match number of rows in design matrix");

  // Load permutations file if supplied
  auto opt = get_options("permutations");
  vector<vector<size_t> > permutations;
  if (opt.size()) {
    permutations = Math::Stats::Permutation::load_permutations_file (opt[0][0]);
    num_perms = permutations.size();
    if (permutations[0].size() != (size_t)design.rows())
       throw Exception ("number of rows in the permutations file (" + str(opt[0][0]) + ") does not match number of rows in design matrix");
  }

  // Load non-stationary correction permutations file if supplied
  opt = get_options("permutations_nonstationary");
  vector<vector<size_t> > permutations_nonstationary;
  if (opt.size()) {
    permutations_nonstationary = Math::Stats::Permutation::load_permutations_file (opt[0][0]);
    nperms_nonstationary = permutations.size();
    if (permutations_nonstationary[0].size() != (size_t)design.rows())
      throw Exception ("number of rows in the nonstationary permutations file (" + str(opt[0][0]) + ") does not match number of rows in design matrix");
  }

  // Load contrast matrix
  const matrix_type contrast = load_matrix<value_type> (argument[2]);
  if (contrast.cols() != design.cols())
    throw Exception ("the number of contrasts does not equal the number of columns in the design matrix");

  auto mask_header = Header::open (argument[3]);
  // Load Mask and compute adjacency
  auto mask_image = mask_header.get_image<value_type>();
  Filter::Connector connector (do_26_connectivity);
  vector<vector<int> > mask_indices = connector.precompute_adjacency (mask_image);
  const size_t num_vox = mask_indices.size();

  matrix_type data (num_vox, subjects.size());

  {
    // Load images
    ProgressBar progress("loading images", subjects.size());
    for (size_t subject = 0; subject < subjects.size(); subject++) {
      LogLevelLatch log_level (0);
      auto input_image = Image<float>::open (subjects[subject]); //.with_direct_io (3); <- Should be inputting 3D images?
      check_dimensions (input_image, mask_image, 0, 3);
      int index = 0;
      vector<vector<int> >::iterator it;
      for (it = mask_indices.begin(); it != mask_indices.end(); ++it) {
        input_image.index(0) = (*it)[0];
        input_image.index(1) = (*it)[1];
        input_image.index(2) = (*it)[2];
        data (index++, subject) = input_image.value();
      }
      progress++;
    }
  }
  if (!data.allFinite())
    WARN ("input data contains non-finite value(s)");

  Header output_header (mask_header);
  output_header.datatype() = DataType::Float32;
  output_header.keyval()["num permutations"] = str(num_perms);
  output_header.keyval()["26 connectivity"] = str(do_26_connectivity);
  output_header.keyval()["nonstationary adjustment"] = str(do_nonstationary_adjustment);
  if (use_tfce) {
    output_header.keyval()["tfce_dh"] = str(tfce_dh);
    output_header.keyval()["tfce_e"] = str(tfce_E);
    output_header.keyval()["tfce_h"] = str(tfce_H);
  } else {
    output_header.keyval()["threshold"] = str(cluster_forming_threshold);
  }

  const std::string prefix (argument[4]);
  bool compute_negative_contrast = get_options("negative").size();

  vector_type default_cluster_output (num_vox);
  std::shared_ptr<vector_type> default_cluster_output_neg;
  vector_type tvalue_output (num_vox);
  vector_type empirical_enhanced_statistic;
  if (compute_negative_contrast)
    default_cluster_output_neg.reset (new vector_type (num_vox));

  Math::Stats::GLMTTest glm (data, design, contrast);

  std::shared_ptr<Stats::EnhancerBase> enhancer;
  if (use_tfce) {
    std::shared_ptr<Stats::TFCE::EnhancerBase> base (new Stats::Cluster::ClusterSize (connector, cluster_forming_threshold));
    enhancer.reset (new Stats::TFCE::Wrapper (base, tfce_dh, tfce_E, tfce_H));
  } else {
    enhancer.reset (new Stats::Cluster::ClusterSize (connector, cluster_forming_threshold));
  }

  if (do_nonstationary_adjustment) {
    if (!use_tfce)
      throw Exception ("nonstationary adjustment is not currently implemented for threshold-based cluster analysis");
    empirical_enhanced_statistic = vector_type::Zero (num_vox);
    if (permutations_nonstationary.size()) {
      Stats::PermTest::PermutationStack permutations (permutations_nonstationary, "precomputing empirical statistic for non-stationarity adjustment...");
      Stats::PermTest::precompute_empirical_stat (glm, enhancer, permutations, empirical_enhanced_statistic);
    } else {
      Stats::PermTest::PermutationStack permutations (nperms_nonstationary, design.rows(), "precomputing empirical statistic for non-stationarity adjustment...", false);
      Stats::PermTest::precompute_empirical_stat (glm, enhancer, permutations, empirical_enhanced_statistic);
    }

    save_matrix (empirical_enhanced_statistic, prefix + "empirical.txt");
  }

  Stats::PermTest::precompute_default_permutation (glm, enhancer, empirical_enhanced_statistic,
                                                   default_cluster_output, default_cluster_output_neg, tvalue_output);

  {
    ProgressBar progress ("generating pre-permutation output", (compute_negative_contrast ? 3 : 2) + contrast.cols() + 3);
    {
      auto tvalue_image = Image<float>::create (prefix + "tvalue.mif", output_header);
      write_output (tvalue_output, mask_indices, tvalue_image);
    }
    ++progress;
    {
      auto cluster_image = Image<float>::create (prefix + (use_tfce ? "tfce.mif" : "cluster_sizes.mif"), output_header);
      write_output (default_cluster_output, mask_indices, cluster_image);
    }
    ++progress;
    if (compute_negative_contrast) {
      assert (default_cluster_output_neg);
      auto cluster_image_neg = Image<float>::create (prefix + (use_tfce ? "tfce_neg.mif" : "cluster_sizes_neg.mif"), output_header);
      write_output (*default_cluster_output_neg, mask_indices, cluster_image_neg);
      ++progress;
    }
    auto temp = Math::Stats::GLM::solve_betas (data, design);
    for (ssize_t i = 0; i < contrast.cols(); ++i) {
      auto beta_image = Image<float>::create (prefix + "beta" + str(i) + ".mif", output_header);
      write_output (temp.row(i), mask_indices, beta_image);
      ++progress;
    }
    {
      const auto temp = Math::Stats::GLM::abs_effect_size (data, design, contrast);
      auto abs_effect_image = Image<float>::create (prefix + "abs_effect.mif", output_header);
      write_output (temp.row(0), mask_indices, abs_effect_image);
    }
    ++progress;
    {
      const auto temp = Math::Stats::GLM::std_effect_size (data, design, contrast);
      auto std_effect_image = Image<float>::create (prefix + "std_effect.mif", output_header);
      write_output (temp.row(0), mask_indices, std_effect_image);
    }
    ++progress;
    {
      const auto temp = Math::Stats::GLM::stdev (data, design);
      auto std_dev_image = Image<float>::create (prefix + "std_dev.mif", output_header);
      write_output (temp.row(0), mask_indices, std_dev_image);
    }
  }

  if (!get_options ("notest").size()) {

    vector_type perm_distribution (num_perms);
    std::shared_ptr<vector_type> perm_distribution_neg;
    vector_type uncorrected_pvalue (num_vox);
    std::shared_ptr<vector_type> uncorrected_pvalue_neg;

    if (compute_negative_contrast) {
      perm_distribution_neg.reset (new vector_type (num_perms));
      uncorrected_pvalue_neg.reset (new vector_type (num_vox));
    }

    if (permutations.size()) {
      Stats::PermTest::run_permutations (permutations, glm, enhancer, empirical_enhanced_statistic,
                                         default_cluster_output, default_cluster_output_neg,
                                         perm_distribution, perm_distribution_neg,
                                         uncorrected_pvalue, uncorrected_pvalue_neg);
    } else {
      Stats::PermTest::run_permutations (num_perms, glm, enhancer, empirical_enhanced_statistic,
                                         default_cluster_output, default_cluster_output_neg,
                                         perm_distribution, perm_distribution_neg,
                                         uncorrected_pvalue, uncorrected_pvalue_neg);
    }

    save_matrix (perm_distribution, prefix + "perm_dist.txt");
    if (compute_negative_contrast) {
      assert (perm_distribution_neg);
      save_matrix (*perm_distribution_neg, prefix + "perm_dist_neg.txt");
    }

    ProgressBar progress ("generating output", compute_negative_contrast ? 4 : 2);
    {
      auto uncorrected_pvalue_image = Image<float>::create (prefix + "uncorrected_pvalue.mif", output_header);
      write_output (uncorrected_pvalue, mask_indices, uncorrected_pvalue_image);
    }
    ++progress;
    {
      vector_type fwe_pvalue_output (num_vox);
      Math::Stats::Permutation::statistic2pvalue (perm_distribution, default_cluster_output, fwe_pvalue_output);
      auto fwe_pvalue_image = Image<float>::create (prefix + "fwe_pvalue.mif", output_header);
      write_output (fwe_pvalue_output, mask_indices, fwe_pvalue_image);
    }
    ++progress;
    if (compute_negative_contrast) {
      assert (uncorrected_pvalue_neg);
      assert (perm_distribution_neg);
      auto uncorrected_pvalue_image_neg = Image<float>::create (prefix + "uncorrected_pvalue_neg.mif", output_header);
      write_output (*uncorrected_pvalue_neg, mask_indices, uncorrected_pvalue_image_neg);
      ++progress;
      vector_type fwe_pvalue_output_neg (num_vox);
      Math::Stats::Permutation::statistic2pvalue (*perm_distribution_neg, *default_cluster_output_neg, fwe_pvalue_output_neg);
      auto fwe_pvalue_image_neg = Image<float>::create (prefix + "fwe_pvalue_neg.mif", output_header);
      write_output (fwe_pvalue_output_neg, mask_indices, fwe_pvalue_image_neg);
    }
  }

}