public boolean[] homozygous(int c, boolean founder) {
        boolean[] result;
        Chromosome chrom = popdata.getChrom(c);
        if (chrom==null || chrom.getLocus()==null ||
                chrom.getLocus().isEmpty()) {
            result = null;
        }
        else {
            result = new boolean[chrom.getLocus().size()];
            Locus locus;
            double locPos;
            int firstFounder;
            String first = null;
            for (int loc=0; loc<result.length; loc++) {
                try {
                    locus = chrom.getLocus().get(loc);
                    locPos = locus.getPosition();
                    firstFounder = haplostruct[c][0].getFounderAt(locPos);
                    if (!founder) first = locus.getAlleleName(firstFounder);
                    result[loc] = true;
                    int h = 1;
                    while (result[loc] && h<haplostruct[c].length) {
                        if (founder) {
                            result[loc] = firstFounder == 
                                haplostruct[c][h].getFounderAt(locPos);
                        } else {
                            result[loc] = first.equals(locus.getAlleleName(
                                haplostruct[c][h].getFounderAt(locPos)));
                        }    
                        h++;
                    }
                }  catch (Exception ex) {/* cannot occur */ }
            }
        }
        return result;
    } //homozygous