Retain statement questions

[brophymj]

I am looking to convert a table like the one below...

Section	Period	Count
1	Q1	1
1	Q2	.
1	Q3	.
1	Q4	2
1	Q5	.
2	Q1	.
2	Q2	1
2	Q3	.
3	Q1	1

into the following table. So, turn the count into a running total for each section.

Section	Period	Count
1	Q1	1
1	Q2	1
1	Q3	1
1	Q4	2
1	Q5	2
2	Q1	0
2	Q2	1
2	Q3	1
3	Q1	1
	...

[RW9]

Hi,

Can you provide some test data in the form of a datastep, as your data is before.  I don't see why you only have number at certain points.  I mean you could do retain, however, why do you only have some numbers, it may be easier to change the way count is added to the dataset rather than retain them afterwards.

[Kurt_Bremser]

data want (drop=oldcount);

set have (rename=(count=oldcount));

by section;

retain count;

if first.section then count = 0;

if oldcount ne . then count=oldcount;

run;

Edit: Replaced zero with dot in second if condition

Post updated: Kurt Bremser

[RW9]

Yes, but it still begs the question, what is the count column, how is it arrived at, i.e. why does Q1 have 1 and Q2 not?  Also, you can't have a Q5.

[data_null__]

Looks like a common LOCF problem to me.

data section;
   infile cards expandtabs;
   input section period :$2. count;
   cards;
1  Q1 1
1  Q2 .
1  Q3 .
1  Q4 2
1  Q5 .
2  Q1 .
2  Q2 1
2  Q3 .
3  Q1 1
;;;;
   run;
proc print;
   run;
data section;
   update section(obs=0 keep=section) section;
   by section;
   if first.section then count=coalesce(count,0);
   output;
   run;
proc print;
   run;