Sas Macro To Reorder Dataset Variables In Alphabetic Order

SAS macro to reorder dataset variables in alphabetic order... How do you reorder variables in a dataset...I get this many a times.... Here's a macro for you to achieve it...For example I've used a dataset sashelp.flags and created some more variables with variety of variables with names upper / lower cases and _'s to demonstrate the reorder macro....

Please try this macro for yourself and let me know your suggestions.... /* Example dataset with variety of variable names */ data flags; set sashelp.flags; a=2; b=4; _common=10; Cool=30; SubJecT=40; run ; %macro reorder(dsn); /* Get the variables names to a dataset using proc contents and keeping the variable name only */ proc contents data=&dsn out=varnames(keep=name) noprint; run;

/* It is very much important that you UPCASE or LOWCASE the variable names... otherwise you get a different order...Remove this datastep and see for yourself... */ data varnames; set varnames; name=lowcase(name); run; /* Sort the variable names in alphabetical order */ proc sort data=varnames; by name; run; /* Get the observation count */ data _null_; set varnames nobs=num; call symput('obscnt',num);/* Get the observation count */ call symput(compress('macvar'||_n_),trim(left(name))); /* Get the variable names into macro variables */ run; %let obscnt=&obscnt; /*remove the leading and trailing blankspaces generated when numeric is converted to Best12. format */ /*Please NOTE that the step of getting all variable names into a macro variable could be simply done by using SQL instead of a macro proc sql noprint; select trim(left(name)) into:macvar separated by ' ' from varnames; quit;

and the next datastep simply data &dsn; retain &macvar; set &dsn; run; But the cons here is that if there are too many variables and the total length of all the names put together crosses 32767 bytes the SQL approach would'nt work... */ data &dsn; retain %do i=1 %to &obscnt; &&macvar&i /* NOTE: there should be a blank space after &&macvar&i to separate the variable names by space eg. retain subject a b c; NOTE: NO semicolon should be typed here*/ %end; set &dsn; run; %mend reorder; %reorder(flags); You might also like: • Ways to Count the Number of Obs in a dataset and pass it into a macro variable... • SAS Interview Questions and Answers(2) • SAS Interview Questions and Answers(1) • SAS macro to Remove a PC Directory...

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