Table 1

NEXUS blocks and common commands

Block name
Commonly used commands
Typical content of block

TAXA
dimensions, taxlabels
Labels for OTUs (may be quoted strings)
CHARACTERS
dimensions, format, matrix
A matrix of character-state data (e.g., aligned residues) of defined type, in a defined format
TREES
tree, translate
Rooted or unrooted trees in Newick format, with optional names and weights for each tree
ASSUMPTIONS
options, usertype, wtset
Constraints on allowed changes; transition cost model; weights for characters
CODONS
codonposset, geneticcode
Description of a reading frame and the genetic code used to translate it
SETS
charset, taxset, treeset
Named sets of OTUs (taxsets), trees, characters, states, or state transitions (changesets)
NOTES
text, picture
Annotations attaching text or pictures to sets of objects including OTUs, characters or trees
DISTANCES
dimensions, format, matrix
Distance matrices
UNALIGNED
dimensions, format, matrix
Unaligned data
DATA1
(see CHARACTERS)
OTU labels and character data (deprecated)

1 The DATA block format, though commonly used, is deprecated so as to encourage use of a separately declared list of OTUs in a TAXA block.

Hladish et al. BMC Bioinformatics 2007 8:191   doi:10.1186/1471-2105-8-191