next up previous contents index
Next: environ.system() execute Up: The environ class: MODELLER Previous: environ.dendrogram() clustering   Contents   Index

environ.principal_components() -- clustering

matrix_file = <str:1> 'family.mat' the filename of the pairwise distance matrix
file = <str:1> 'default' output file

Description:
This command calculates principal components clustering for the input matrix of pairwise distances. This matrix must be in the PHYLIP format and can be produced by the alignment.id_table(), alignment.compare_sequences(), or alignment.compare_structures() commands.

The projected coordinates $p$ and $q$ are written to file file. The output file can be used with ASGL to produce a principal components plot.

This command is useful for deciding about which known 3D structures are to be used as templates for comparative modeling.

Example: See alignment.id_table() command.



Ben Webb 2006-02-28