Hi,
I need to assign a customer category in a new variable (Derived_Customer_Cat) to each customer record based on the first valid value of a variable (Customer_Cat) for all records of the same customer (Customer_ID). And the following code is a demonstration of what I have and want.
Can you help me find an efficient approach? Thank you!
Jason
data have;
input Customer_ID $1 Customer_Cat $3;
datalines;
1 A
1 A
1 A
2
2 B
2 B
3
3
3 A
3 C
4
4
4 C
4 D
4 D
4
;
run;
data want;
input Customer_ID $1 Customer_Cat $3 Derived_Customer_Cat $5;
datalines;
1 A A
1 A A
1 A A
2 B
2 B B
2 B B
3 A
3 A
3 A A
3 C A
4 C
4 C
4 C C
4 D C
4 D C
4 C
;
run;
Please try
data have;
input Customer_ID $1 Customer_Cat $3 ;
datalines;
1 A
1 A
1 A
2
2 B
2 B
3
3
3 A
3 C
4
4
4 C
4 D
4 D
4 C
;
run;
data first;
set have;
by Customer_ID;
where Customer_Cat ne '';
if first.Customer_ID;
Derived_Customer_Cat =Customer_Cat;
keep Customer_ID Derived_Customer_Cat;
run;
data want2;
merge have(in=a) first(in=b) ;
by Customer_ID;
if a;
run;
... based on the first valid value ...
What is a "valid value"?
I should have said "non-missing" value.
Sorry the datalines for "want" got shifted. And here is what the data steps should be:
data have;
input Customer_ID $1 Customer_Cat $3;
datalines;
1 A
1 A
1 A
2
2 B
2 B
3
3
3 A
3 C
4
4
4 C
4 D
4 D
4
;
run;
data want;
input Customer_ID $1 Customer_Cat $3 Derived_Customer_Cat $5;
datalines;
1 A A
1 A A
1 A A
2 B
2 B B
2 B B
3 A
3 A
3 A A
3 C A
4 C
4 C
4 C C
4 D C
4 D C
4 C C
;
run;
Please try
data have;
input Customer_ID $1 Customer_Cat $3 ;
datalines;
1 A
1 A
1 A
2
2 B
2 B
3
3
3 A
3 C
4
4
4 C
4 D
4 D
4 C
;
run;
data first;
set have;
by Customer_ID;
where Customer_Cat ne '';
if first.Customer_ID;
Derived_Customer_Cat =Customer_Cat;
keep Customer_ID Derived_Customer_Cat;
run;
data want2;
merge have(in=a) first(in=b) ;
by Customer_ID;
if a;
run;
Thank you! This works.
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