init_param: Initialize EM parameters given group assignments
In diem: Debris-Containing Droplet Identification using EM

Initialize EM parameters given group assignments

1	init_param(counts, groups, psc = 1e-04)

`counts`	an observation by variable matrix of non-negative integer counts.
`groups`	A character vector or factor, the same length as the number of columns in counts. The assignment of the index in groups corresponds to the group assignment of the column index in counts. Thus, the ordering of groups must be consistent with the column ordering in counts.
`psc`	Pseudocount to add to the resulting mean for each multinomial mean parameter.