SAS Enterprise Guide 7.1
I'm trying to write codes to complete the following task:
Here are two datasets
Dataset A Dataset B
Var1 Var2 Var3 Var4
x1.1 x1.2 y1.1 y1.2
x2.1 x2.2 y2.1 y2.2
And the generated dataset/table should be
Dataset C
VarY
z1
z2
z3
z4
whereas z1 = FUNCTION(x1.1,x1.2,y1.1,y1.2)
z2 = FUNCTION(x1.1,x1.2,y2.1,y2.2)
z3 = FUNCTION(x2.1,x2.2,y1.1,y1.2)
z4 = FUNCTION(x2.1,x2.2,y2.1,y2.2)
Var1, Var2, Var3, Var4, VarY are column/variable names.
FUNCTION in this case could be
GEODIST(latitude-1, longitude-1, latitude-2, longitude-2, );
Not sure how to do it, probably Do/Loop is needed?
No loop, this is called a CROSS JOIN or cartesian product where all rows are matched with all other rows.
With regard to combing the datasets then a simple sql code should be good to create a cartesian product. However i am not sure how we could use the function. a catx function could be used to concatenate the var1-var4.
data A;
input Var1$ Var2$;
cards;
x1.1 x1.2
x2.1 x2.2
;
data b;
input Var3$ Var4$;
cards;
y1.1 y1.2
y2.1 y2.2
;
proc sql;
create table test as select a.*, b.* from a as a , b as b;
quit;
No loop, this is called a CROSS JOIN or cartesian product where all rows are matched with all other rows.
Here's one approach to assemble all the needed information:
data want;
set a;
set b;
prior_var1 = lag(var1);
prior_var2 = lag(var2);
prior_var3 = lag(var3);
prior_var4 = lag(var4);
if _n_ > 1 then do;
VarY = geodist(prior_var1, prior_var2, prior_var3, prior_var4);
output;
VarY = geodist(prior_var1, prior_var2, var3, var4);
output;
VarY = geodist(var1. var2. prior_var3, prior_var4);
output;
VarY = geodist(var1, var2, var3, var4);
output;
end;
keep VarY;
run;
It's finally time to hack! Remember to visit the SAS Hacker's Hub regularly for news and updates.
Check out this tutorial series to learn how to build your own steps in SAS Studio.
Find more tutorials on the SAS Users YouTube channel.
Ready to level-up your skills? Choose your own adventure.