As a simplified example of what I am currently working on...   Suppose I want to compare the performance of Roger Federer, Novak Djokovic, and Rafa Nadal in several Grand Slam tournaments last year. And suppose that I have a few datasets that contain each player's performance (such as 1st and 2nd serve win rate) and these datasets are named in the following manner:       player_tournament_round  (e.g  Federer_USOpen_round1, Nadal_Wimbledon_round4)   Suppose that I am only interested in the first 2 rounds of US Open, rounds 3-5 of Wimbledon, and first 4 rounds of Australian Open (assuming that the players attended all of these matches).   So I already have a macro called 'input' that reads in these datasets and performs some tweaks, and it is specified as:       %macro input(player, tour, round);   In SAS, I invoked the macro as follows:     %input(Federer, USOpen, round1);   %input(Federer, USOpen, round2);   %input(Federer, Wimbledon, round3);   %input(Federer, Wimbledon, round4);   %input(Federer, Wimbledon, round5);   %input(Federer, AUOpen, round1);   %input(Federer, AUOpen, round2);   %input(Federer, AUOpen, round3);   %input(Federer, AUOpen, round4);     %input(Djokovic, USOpen, round1);   %input(Djokovic, USOpen, round2);   %input(Djokovic, Wimbledon, round3);   %input(Djokovic, Wimbledon, round4);   %input(Djokovic, Wimbledon, round5);   %input(Djokovic, AUOpen, round1);   %input(Djokovic, AUOpen, round2);   %input(Djokovic, AUOpen, round3);   %input(Djokovic, AUOpen, round4);     %input(Nadal, USOpen, round1);   %input(Nadal, USOpen, round2);   %input(Nadal, Wimbledon, round3);   %input(Nadal, Wimbledon, round4);   %input(Nadal, Wimbledon, round5);   %input(Nadal, AUOpen, round1);   %input(Nadal, AUOpen, round2);   %input(Nadal, AUOpen, round3);   %input(Nadal, AUOpen, round4);   -------------------------------------------------- As you can see, the macro invocation becomes quite redundant, because, for each player, I always need to enter rounds 1-2 for US Open, rounds 3-5 for Wimbeldon, and rounds 1-4 for AU Open.   So my question is: how do I tell SAS to automatically do:   rounds 1-2 if &tour. = USOpen   rounds 3-5 if &tour. = Wimbledon   rounds 1-4 if &tour. = AUOpen   I have some thoughts, such as an array (do loop) or nested macro, but I have not been able to code it. Some help will be much appreciated!     ... View more