Skip to content

Fix Chinese Whispers clustering to process all nodes each iteration #3133

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
SamareshSingh wants to merge 1 commit into
base: master
Choose a base branch
from
+28 −18
Open

Fix Chinese Whispers clustering to process all nodes each iteration #3133

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
46 changes: 28 additions & 18 deletions dlib/clustering/chinese_whispers.h
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -39,33 +39,43 @@ namespace dlib
labels[i] = i;


for (unsigned long iter = 0; iter < neighbors.size()*num_iterations; ++iter)
for (unsigned long iter = 0; iter < num_iterations; ++iter)
{
// Pick a random node.
const unsigned long idx = rnd.get_random_64bit_number()%neighbors.size();
std::vector<unsigned long> node_order;
for (unsigned long i = 0; i < neighbors.size(); ++i)
node_order.push_back(i);

// Count how many times each label happens amongst our neighbors.
std::map<unsigned long, double> labels_to_counts;
const unsigned long end = neighbors[idx].second;
for (unsigned long i = neighbors[idx].first; i != end; ++i)
for (unsigned long i = node_order.size(); i > 1; --i)
{
labels_to_counts[labels[edges[i].index2()]] += edges[i].distance();
unsigned long j = rnd.get_random_64bit_number() % i;
std::swap(node_order[j], node_order[i-1]);
}

// find the most common label
std::map<unsigned long, double>::iterator i;
double best_score = -std::numeric_limits<double>::infinity();
unsigned long best_label = labels[idx];
for (i = labels_to_counts.begin(); i != labels_to_counts.end(); ++i)
for (unsigned long n = 0; n < node_order.size(); ++n)
{
if (i->second > best_score)
const unsigned long idx = node_order[n];

std::map<unsigned long, double> labels_to_counts;
const unsigned long end = neighbors[idx].second;
for (unsigned long i = neighbors[idx].first; i != end; ++i)
{
best_score = i->second;
best_label = i->first;
labels_to_counts[labels[edges[i].index2()]] += edges[i].distance();
}

std::map<unsigned long, double>::iterator i;
double best_score = -std::numeric_limits<double>::infinity();
unsigned long best_label = labels[idx];
for (i = labels_to_counts.begin(); i != labels_to_counts.end(); ++i)
{
if (i->second > best_score)
{
best_score = i->second;
best_label = i->first;
}
}
}

labels[idx] = best_label;
labels[idx] = best_label;
}
}


Expand Down
Loading