REF Method
Consolidates the FIND and ADD methods into a single
method call.
| Applies to: | Hash object |
Syntax
rc=object.REF(<<KEY: keyvalue-1>, ...<KEY: keyvalue-n>, <DATA: datavalue-1>
, ...<DATA: datavalue-n>>);
, ...<DATA: datavalue-n>>);
Details
You can consolidate
FIND and ADD methods into a single REF method. You can change the
following code:
rc = h.find();
if (rc ne = 0) then
rc = h.add();torc = h.ref();
The REF method is useful
for counting the number of occurrences of each key in a hash object.
The REF method initializes the key summary for each key on the first
ADD, and then changes the ADD for each subsequent FIND.
Note: The REF method sets the data
variable to the value of the data item so that it is available for
use after the method call.
For more
information about key summaries, see Maintaining Key Summaries in SAS Language Reference: Concepts.
Example: Using the REF Method for Key Summaries
The following example
uses the REF method for key summaries:
data keys;
input key;
datalines;
1
2
1
3
5
2
3
2
4
1
5
1
;
data count;
length count key 8;
keep key count;
if _n_ = 1 then do;
declare hash myhash(suminc: "count", ordered: "y");
declare hiter iter("myhash");
myhash.defineKey('key');
myhash.defineDone();
count = 1;
end;
do while (not done);
set keys end=done;
rc = myhash.ref();
end;
rc = iter.first();
do while(rc = 0);
rc = myhash.sum(sum: count);
output;
rc = iter.next();
end;
stop;
run;
proc print data=count;
run;