Compute the number of interactions/interaction strength between cell types based on their associated cell subpopulations
mergeInteractions(object, group.merged)
CellChat object
a factor defining the group for merging different clusters/subpopulations
An updated slot `net` by adding three elements:
`count.merged`: the number of interactions between cell types (i.e., merged cell groups)
`weight.merged`: interaction strength between cell types (i.e., merged cell groups)
`group.merged` the defined group for merging different clusters/subpopulations