Tree Output 

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A tree generated by ClustanGraphics for a hierarchical cluster analysis can be viewed and saved in different formats, currently dendrogram and NEXUS formats.  These are selected in the View Tree Data dialogue on the Edit menu, as follows:

Displays and saves tree data in different formats

Dendrogram format, which is illustrated above, can be re-read by Clustan/PC and ClustanGraphics.

NEXUS format is useful if several trees are to be compared and a "consensus" tree found that reflects any common structure between them.  An example of NEXUS format is as follows:

Tree = (((12,((13,(15,17)),(8,16))),((((25,3),(14,1)),9),((2,(23,10)),((18,11),4)))),((((6,20),((5,21),24)),19),(7,22)))

As can be seen from the dialogue, a tree can also be displayed using case labels; for example:

(((Hippo,((Horse,(Monkey,Orangutan)),(Donkey,Mule))),((((Zebra,Camel),(Llama,Bison)),Elephant),((Buffalo,(S heep,Fox)),((Pig,GuineaPig),Cat)))),((((Dog,Rat),((Deer,Reindeer),Whale)),Rabbit),(Dolphin,Seal)))

This corresponds to the following optimally re-ordered tree:

ClustanGraphics tree for Mammals Milk case study, optimally re-ordered

Trees of any size can be saved to a text file.  Where they have been derived from a proximity matrix, the underlying case order of the tree can also be optimally re-ordered, as in the above example, before being saved in NEXUS format.