dot-doFC: Generate the fold change
In markrobinsonuzh/treeAGG: Tree Aggregation

.doFC generates fold changes for different scenarios

1 2	.doFC(tree = NULL, data = NULL, scenario = "S1", branchA = NULL, branchB = NULL, ratio = 1, adjB = NULL, pct = 1)

`tree`	A phylo object
`data`	The real data (count table)
`scenario`	Scenarios (“S1”, “S2”, “S3”)
`branchA`	The branch node label of branch A.
`branchB`	The branh node label of branch B.
`ratio`	The proportion ratio between `branchB` and `branchA` (B/A)
`adjB`	A numeric value between 0 and 1 (only for `scenario` is “S3”). Default is NULL. If NULL, branch A and branch B swap their proportions. If a numeric value, e.g. 0.1, then branch B decreases to its one tenth proportion and the decrease in branch B is added to branch A. For example, assume there are two experimental conditions (C1 & C2), branch A has 10 and branch B has 40 in C1. If adjB is set to 0.1, then in C2 branch B becomes 4 and branch A 46 so that the total proportion stays the same.
`pct`	The percentage (in number) of the leaves in branchA that will swap with branchB. The default is 1.