counting total number of distinct observation

[babymonster]

Hi everyone,

I have a data set that contain a variable similar to this example,

number

56

56

56

58

58

60

61

61

61

61

61

...

I would like to know the total count of distinct number. In this example is 4 (56, 58, 60, and 61). 

How can i do it in SAS? I think i can do

proc sort data= mydata out=dataout noduplications;

... 

then use proc freq or proc means

but is that a clever way?

thanks 

[Shmuel · Accepted solution]

There are more than one way to get the amount of distinct values of a variable:

1) Using proc sort with nodupkey - just check number of output observations in log or check output dataset.

2) Use proc sql - select distinct variable and end with:

quit;
%put &sqlobs;

  then check the log;

3) Assuming your data is sorted by the variable then do:

data _null_;
   set have end=eof;
        retain distinct_count 0;
    by var;
        if eof then put   distinct_count =;
        if first.var then  distinct_count  +1;
run;

  and check the log;

[babymonster]

Thanks Shmuel

[RW9]

You want to do a frequency count, therefore use proc freq(uency) - this is logical and why they called the procedure that name

[ballardw]

And an example using the Proc Freq nlevels option:

ods select nlevels;
proc freq data=sashelp.class nlevels;
   tables sex;
run;

the ODS Select nlevels; instructs SAS to only show the levels information which would be the number of unique values and missing values if any.