R/findmin.R

In QCA: Qualitative Comparative Analysis

# Copyright (c) 2016 - 2023, Adrian Dusa
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# 
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`findmin` <- function(chart, ...) {
    dots <- list(...)
    if (!methods::is(chart, "QCA_pic")) {
        if (!is.matrix(chart) | (!is.logical(chart) & length(setdiff(chart, 0:1)) > 0)) {
            admisc::stopError(
                "Use a logical, TRUE/FALSE matrix. See makeChart()'s output.",
                ... = ...
            )
        }
    }
    if (is.null(attr(chart, "C_PI"))) {
        chart <- t(chart)
    }
    if (all(colSums(chart) > 0)) {
        solution <- lpSolve::lp(
            "min",
            rep(1, ncol(chart)),
            chart,
            ">=",
            1,
            int.vec = seq(nrow(chart))
        )$solution
        result <- as.integer(sum(solution))
    }
    else {
        result <- 0L
    }
    class(result) <- c("integer", "QCA_findmin")
    return(result)
}