Normalizes the props parameter for match_groups().
.normalize_props(props, condition, keep_last_item = FALSE)A named vector: if props contains proportions, it is the same, but ordered to follow the levels of condition; if props contains names of conditions, the total number of subjects for the condition names in props.
Either the desired proportions (percentage) of the sample for each condition as a named vector, or the names of the conditions for which we prefer to preserve the subjects, in decreasing order of preference. If not specified, the (full) sample proportions are used. This is preferred among configurations with the same taken into account by the other methods to some extent. For example, c(A = 0.4, B = 0.4, C = 0.2) means that we would like the number of subjects in groups A, B, and C to be around 40%, 40%, and 20% of the total number of subjects, respectively. Whereas c("A", "B", "C") means that if possible, we would like to keep all subjects in group A, and prefer keeping subjects in B, even if it results in losing more subjects from C.
A factor vector containing condition labels.
If TRUE and props is a character vector, last item is not dropped.