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From: Raj on 1 Aug 2010 04:17
Hi,

Can somebody explain where we use VAR,ID,BY,CLASS and what is the
difference between each one with an example.

Thanks for the help.

Regards,
Raj
From: Bob on 1 Aug 2010 08:12
Here is a good article from SAS on the PROC SUMMARY. That is the
procedure where those are primarily used.

http://support.sas.com/documentation/cdl/en/proc/61895/HTML/default/viewer.htm#/documentation/cdl/en/proc/61895/HTML/default/a002473735.htm

CLASS and BY are used to tell SAS what variable(s) to use when
summarizing the dataset. (The difference being BY variables must be
presorted). ID is used to tell SAS, 'don't summarize by this variable,
but display the first value for a given BY variable combination'. VAR
is used for numeric variables you would like a calculation performed
on (usually summation).

Example:
proc summary data=[input dataset] nway missing;
class [var1] [var2];
id [var3];
var [var4];
output out=[output dataset] sum=;
run;

This summarizes the input dataset by var1 and var2, displays var3, and
subtotals var4 for each var1/var2 combination. Make sense?



On Aug 1, 3:17 am, Raj <rajiv...(a)gmail.com> wrote:
> Hi,
>
> Can somebody explain where we use VAR,ID,BY,CLASS and what is the
> difference between each one with an example.
>
> Thanks for the help.
>
> Regards,
> Raj

From: Arthur Tabachneck on 1 Aug 2010 09:28
Raj,

I'd expand on Bob's response and make a couple of minor corrections.

First, the concepts aren't limited to proc summary, but are general to
many SAS procs. In fact, the documentation provides a lot more detail
in its section on proc summary's relative .. proc means (see, e.g.:
http://support.sas.com/documentation/cdl/en/proc/61895/HTML/default/viewer.htm#/documentation/cdl/en/proc/61895/HTML/default/a000146728.htm

or, in short form: http://xrl.us/bhuwpz )

In some procs, 'table' or 'model' might be the keyword used rather
than 'var'.

The 'by' statement gives you a way to mix orders so that all don't
have to be ascending or descending, lets you use the #byval variable
and, I believe, requires less resources (thus can handle more complex
designs before confronting memory problems).

The ID statement gives you a way to include additional, non-summarized
values. The documentation provides more detail than I could provide
here but, rather than the first value encountered in a by or class
group combination, it can either be the minimum or maximum value
within a by or class group combination.

HTH,
Art
---------------
On Aug 1, 8:12 am, Bob <techsavvy...(a)yahoo.com> wrote:
> Here is a good article from SAS on the PROC SUMMARY. That is the
> procedure where those are primarily used.
>
> http://support.sas.com/documentation/cdl/en/proc/61895/HTML/default/v...
>
> CLASS and BY are used to tell SAS what variable(s) to use when
> summarizing the dataset. (The difference being BY variables must be
> presorted). ID is used to tell SAS, 'don't summarize by this variable,
> but display the first value for a given BY variable combination'. VAR
> is used for numeric variables you would like a calculation performed
> on (usually summation).
>
> Example:
> proc summary data=[input dataset] nway missing;
>      class [var1] [var2];
>      id [var3];
>      var [var4];
>      output out=[output dataset] sum=;
> run;
>
> This summarizes the input dataset by var1 and var2, displays var3, and
> subtotals var4 for each var1/var2 combination. Make sense?
>
> On Aug 1, 3:17 am, Raj <rajiv...(a)gmail.com> wrote:
>
>
>
> > Hi,
>
> > Can somebody explain where we use VAR,ID,BY,CLASS and what is the
> > difference between each one with an example.
>
> > Thanks for the help.
>
> > Regards,
> > Raj- Hide quoted text -
>
> - Show quoted text -

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