Gerhard Hellriegel wrote: > example: > > %macro double(x); > %let res=%eval(&x*2); > &res; > %mend; > > %let test=%double(8); > > > But be careful with the usage: > > data a; > set sashelp.class; > *double_age=%double(age); /* this will not work */ > quad_age=age*%double(2); > put quad_age; > run; > > Regards, > Gerhard > You must be aware that the macro will resolve before the program is run, so the value of age is not known at the time the macro is resolved. If you want to resolve a macro during execution, you need to use the resolve function: double_age=resolve('%double('!!put(age,2.)!!')'''); Documentation: http://support.sas.com/onlinedoc/913/getDoc/no/mcrolref.hlp/a000210258.htm Stig