K-Medoids 3D Similarity Clustering

Category Paths

Follow one of these paths in the Orion user interface, to find the floe.

  • Role-based/Medicinal Chemist

  • Task-based/Data Science/Clustering

  • Solution-based/Virtual-screening/Analysis/Clustering

Description

This floe clusters datasets using OEShape 3D similarity calculations and sklearn K-Medoids clustering.

One benefit of K-Medoids is that it allows the user to select the number of clusters. See the “Number of K-Medoids Clusters” parameter to control this.

This Floe uses OEShape for 3D similarity calculation. If (and only if) the primary molecule field on the input dataset does not have 3D coordinates, the floe will use OMEGA to generate a single conformer for each record in the primary molecule field and do similarity calculations with this molecule.

This Floe has to cache records and generate an NxN similarity matrix, therefore, it is expensive and not recommended for handling an input dataset with more than 20K input records, and the floe will fail automatically for input datasets larger than 30K records.

The Floe can generate the following datasets:

  • A members dataset that will contain each molecule from the input dataset with its corresponding cluster ID.

  • A cores dataset that contains one representative from each cluster.

  • A singletons dataset that contains any clusters with only one member.

Promoted Parameters

Title in user interface (promoted name)

3D Similarity Calculation

3D Similarity Score Function (score_type):

  • Type: string

  • Default: Tanimoto Combo

  • Choices: [‘Shape Tanimoto’, ‘Color Tanimoto’, ‘Tanimoto Combo’]

Align Molecules (use_align): If set to True, molecules will be aligned before similarity calculation; otherwise, they will retain input coordinates.

  • Type: boolean

  • Default: True

  • Choices: [True, False]

Similarity Score Cutoff (sim_cutoff): Similarity scores below this value will be calculated as 0

  • Type: decimal

  • Default: 0.05

Outputs

Cluster Medoids (medoids): Name of output medoids dataset

  • Type: dataset_out

  • Default: 3D_KMedoids_clustering_medoids

Failed Records (failed): Dataset with failed records.

  • Required

  • Type: dataset_out

  • Default: 3D_KMedoids_clustering_failed

Cluster Members (members): Name of output member dataset, containing all cluster members.

  • Required

  • Type: dataset_out

  • Default: 3D_KMedoids_clustering_members

Floe Report Name (cluster_report_name):

  • Type: string

  • Default: 3D_KMedoids_clustering_report

Singletons (singletons): Name of output singletons dataset, containing clusters with only one member.

  • Type: dataset_out

  • Default: 3D_KMedoids_clustering_singletons

Inputs

Input Dataset (in): Dataset to cluster

  • Required

  • Type: data_source

Advanced: Sort Input Dataset By Score

Use Score (use_rank): Use rank to sort hits in directed sphere exclusion algorithm and include rank information in clustering report. YOU MUST SELECT A SCORE FIELD IN THE SCORE FIELD PARAMETER, BELOW, IF THIS IS SET TO TRUE.

  • Type: boolean

  • Default: False

  • Choices: [True, False]

Score Field (rank_field): Score field to be used for sorting during sphere exclusion and analyzed in floe report.

  • Type: field_parameter

Score Sort Order (sort_order): Sort order for scores. Descending means higher scores are more desirable. Ascending means lower scores are more desirable.

  • Type: string

  • Default: Descending

  • Choices: [‘Descending’, ‘Ascending’]

Advanced: Memory, Optimization, and Matrix File Output or Input

Output Distance Matrix (output_similarity_matrix): If True, writes distance matrix used in clustering to a file.

  • Type: boolean

  • Default: False

  • Choices: [True, False]

Distance Matrix Filename (similarity_matrix_filename): Filename of distance matrix.

  • Type: string

  • Default: clustering_distance_matrix.txt

Memory for Clustering Cubes (clustering_memory): For large datasets, try increasing the memory limit.

  • Type: decimal

  • Default: 8000

Similarity Tile Size (tile_size): Advanced parameter for tuning parallel speed.

  • Type: integer

  • Default: 5

K-Medoids

Number of K-Medoids Clusters (n_clusters):

  • Required

  • Type: integer

  • Default: 10

Advanced: K-Medoids

Medoid Initialization Method (init_method): From scikit-learn-extra docs: Specify medoid initialization method. ‘random’ selects n_clusters elements from the dataset. ‘heuristic’ picks the n_clusters points with the smallest sum distance to every other point. ‘k-medoids++’ follows an approach based on k-means++_, and in general, gives initial medoids which are more separated than those generated by the other methods. ‘build’ is a greedy initialization of the medoids used in the original PAM algorithm. Often ‘build’ is more efficient but slower than other initializations on big datasets and it is also very non-robust, if there are outliers in the dataset, use another initialization.

  • Required

  • Type: string

  • Default: heuristic

  • Choices: [‘random’, ‘heuristic’, ‘k-medoids++’, ‘build’]

Algorithm (method): Alternate is faster, pam is more accurate

  • Required

  • Type: string

  • Default: pam

  • Choices: [‘alternate’, ‘pam’]

Maximum K-Medoids Iterations (max_iter):

  • Required

  • Type: integer

  • Default: 100000