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Main topics: ARB: a Short Introduction Glossary NTREE MODES (general info) | Related topics: Multifurcate tree
# LENGTH and MULTIFURC MODE OCCURRENCE DESCRIPTION Differences between LENGTH- and MULTIFURC-MODES NOTES EXAMPLES WARNINGS BUGS ## OCCURRENCE
### ARB_NT <button in the left column>
## DESCRIPTION
### Both modes described here allow you to increase or reduce the length of terminal and internal branches. ### Click on the eleventh resp. twelfth button in the left column of the 'ARB_NT' window to activate the 'LENGTH MODE' resp. 'MULTIFURC MODE'. ### Change branch length: Click and drag a branch to change its length. If you use the right mouse button, discrete values will be used for the length. ### Set branch length to zero: Point to a branch with the mouse and hit the key '0' (zero).
## Differences between LENGTH- and MULTIFURC-MODES
### The LENGTH MODE simply changes the length of the targeted branch. ### The MULTIFURC-MODE changes the length of the targeted branch as well, but also distributes its length-change to its direct (non-zero-length) neighbour-branches. Distribution is based on the same algorithm as ´Multifurcate tree´.
## NOTES
### To multifurcate explicit single branches, you may as well focus the tree-display, move the mouse pointer to the bootstrap value of the branch to eliminate and then press '0' to actually eliminate the branch. ### Increasing the length of a branch in MULTIFURC-MODE may cause neighbour branches to become multifurcations. This is irreversible, i.e. reducing the length back to the original value will not "un-multifurcate" the affected branches. ### In both modes it is possible to set branchlengths to negative values if expert-mode is enabled.
## EXAMPLES
### None
## WARNINGS
### In MULTIFURC MODE you may not expect to undo all length distributions, by scaling the branchlength back to the original value it had before a previous scale operation!
## BUGS
### unknown