SAS array dimension error -

data t1;     m = 4;     array a1{m} _temporary_ (2, 3*1);     array a2{m} _temporary_(4*.); run;   error: many variables defined dimension(s) specified array tables. error 22-322: syntax error, expecting 1 of following: integer constant, *.    error 202-322: option or parameter not recognized , ignored. 

why can't define dimension of array other variables?

you cannot define dimension that, rather can use macro achieve same below

 %let   m = 4;   data t1;     array a1{&m.} _temporary_ (2, 3*1);     array a2{&m.} _temporary_(4*.); run;