topic Re: Using Arrays to check equality of groups of strings in SAS Programming

Using Arrays to check equality of groups of strings

mattteale — Wed, 11 Apr 2018 09:58:56 GMT

Hi,

By way of example, I have two groups of strings as shown below, a1-a3 and b1-b3.

I want to know if at least one of the strings in a1-a3 is equal to at least one of the strings in b1-b3. Then flag the rows which satisfy this.

I imagine this will be done using arrays and a do loop. I realise my attempt in the code below will only work if all a1-a3 are identical to b1-b3.

I would really appreciate some help here.

Thanks a lot

Matt

data table ;
input a1 $ a2 $ a3 $ b1 $ b2 $ b3 $ match $ ;
cards ;
a b c a b c Yes
a b c a d e Yes 
a b c d e f no 
a b c a b e Yes
; 
run ;

data table ;
set table ;
array check1 a1-a3 ;
array check2 b1-b3 ;
do i=1 to 3 ;
if check1(i)=check2(i) then match =1 ;
else match=0 ;
end ;
run ;

Re: Using Arrays to check equality of groups of strings

Kurt_Bremser — Wed, 11 Apr 2018 10:09:18 GMT

Just a little change in the logic:

data table;
set table;
array check1 a1-a3;
array check2 b1-b3;
match = 0;
do i = 1 to 3;
  if check1{i} = check2{i} then match = 1;
end;
run;

Re: Using Arrays to check equality of groups of strings

RW9 — Wed, 11 Apr 2018 10:11:02 GMT

Something like:

data table ;
  input a1 $ a2 $ a3 $ b1 $ b2 $ b3 $;
cards ;
a b c a b c
a b c a d e
a b c d e f 
a b c a b e
; 
run;

data want;
  set table;
  array a{3};
  do i=1 to dim(a);
    if whichc(a{i},of b:) then match="yes";
  end;
run;

Re: Using Arrays to check equality of groups of strings

mattteale — Wed, 11 Apr 2018 10:12:33 GMT

Thank you so much pal