if (scalar(@ARGV) == 0) {
print "Usage: rsem-generate-data-matrix sampleA.[alleles/genes/isoforms].results sampleB.[alleles/genes/isoforms].results ... > output_name.matrix\n";
if (scalar(@ARGV) == 0) {
print "Usage: rsem-generate-data-matrix sampleA.[alleles/genes/isoforms].results sampleB.[alleles/genes/isoforms].results ... > output_name.matrix\n";