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1、Coders'CornerPaper73-26ThatMysteriousColon(:)HaipingLuo,Dept.ofVeteransAffairs,Washington,DCwhenxisnotequaltoy.Thestatement‘return;’bringstheexecutionbacktothebeginningofthedatastepforthenextABSTRACTobservation,withoutexecutingthetwostatementsafterthe‘yes:’Thec
2、olon(:)playscertainrolesinSAScoding.Itsusage,label.Onlywhenthecondition'x=y'ismet,willtheprogramjumphowever,isnotwelldocumentednorisitclearlyindexedinSAStothelabel‘yes:’andexecutethetwostatementswhichfollowthemanuals.Thispapershowshowacoloncanbeusedasalabellabe
3、l.Thevalueofxandzwillbeprintedtothelog,theindicator,anoperatormodifier,aformatmodifier,akeywordobservationwillbedeletedandthethentheprogramwillreadincomponent,avariablenamewildcard,anarraybounddelimiter,thenextobservation.anargumentfeaturedelimiter,aspeciallogi
4、ndicator,oranindexcreationoperator.MasteringtheseusagescangiveyourcodeSimilarly,aLINKstatementalsobranchesexecutiontoneededfunctionalityand/oranefficiencylift.statementsafteralabel.ThedifferencebetweentheGOTOandtheLINKstatementsisthataftertheexecutionthecodefol
5、lowingANOVERVIEWthelabel(thelabeledstatementgroup),a‘return;’statementinaInSASlanguage,thecolon(:)hasmanydifferentuses,althoughLINKstructurewillbringexecutiontothestatementfollowingthetheyarenotwelldocumented.ItisdifficulttosearchfortheLINKstatement,whilea‘retu
6、rn;’inaGOTOstructurewillbringcolon’susageinSASOnlineDoc,SystemHelp,andprintedexecutiontothebeginningofthedatastep.Theuseoflabelinamanuals.Fromthescattereddocumentations,publications,andLINKstructurecanbeseeninthefollowingexample:featuredprogrammers,thispapercol
7、lectedninetypesofcolondataworkers;usages:settickets;byssn;1.Labelindicatoriffirst.ssnthenlinkinit;2.Formatmodifiertickets+1;3.Operatormodifiertothrs+hours;4.Keywordcomponentiflast.ssnthenoutput;5.Variablenamewildcardreturn;6.Arraybounddelimiterinit:7.Argumentfe
8、aturedelimitertickets=0;8.Speciallogindicatortothrs=0;9.Indexcreationoperatorreturn;SomeoftheseusagescanimprovecodingefficiencywhileothersThisdatastepsumsticketsandtotalhour
