PLSguiisaMATLABprogramwithagraphicuserinterface(GUI)drivenbymessagesfrommouseandkeyboard.Asanalternative,thisuserinterfacecanalsobedrivenbybatch_plsguicommand(seeBatchProcess),whichispartofPLSguiprogram.PLScmdprogram(seeAppendixB)isacommand-linePLS,anditisaseparateprogramthatis