check whether a variable exists in a sas dataset

VARNUM checks whether the variable &name exists

Modify the default ODS graphics behavior from statistical procedures

Those ODS graphics in the statistical procedures are predefined template using Graphics template language(GTL). Using ods trace on to find the name of that graph template. Then you have two ways to modify them.

split data

1000 size sample, variable: ID_no from 1-1000
how to split it to two new data sets: one with even numbers for ID_no, the othe one with odds number for ID_no?

data set1 set2;
set yourdata;
if mod(id, 2) = 0 then output set1;
else output set2;
run;

estimate statements

In your LSMEANS statement, add an option e, SAS should print out an estimate statement for you. That will be an excellent example.

write a sas dataset to a flat file

filename myfile "d:\temp\a.txt";
data _null_;
set mydata;
file myfile;
put id 1-3 var2 4-10 var3 11-15 ;
run;

change the default number of digits in P values

proc template;
edit Common.PValue;
format=best16.;
end;
run;

download data with URL

FILENAME myurl URL "http://ichart.finance.yahoo.com/table.csv?s=&tic";

DATA &tic;
INFILE myurl FIRSTOBS=2 missover dsd;
format date yymmdd10.;
INPUT Date: yymmdd10. Open High Low Close Volume Adj_Close
;
if date>=today()-180;

RUN;

randomly select 300 samples

Proc Surveyselect
data=old data method=sys/srs/etc. sampsize=300 out=new data;
run;

superscript to ODS RTF

Google is your best friend:
http://www2.sas.com/proceedings/forum2008/033-2008.pdf

ods rtf file="C:\test.rtf";
ods escapechar= '\';
proc tabulate data=sashelp.class style={cellwidth=100};
class sex;
var age;
table sex,age;
label age= "age\{super 1}";
run;
ods rtf close;

select statement example

SELECT (payclass);
     WHEN ('monthly') amt=salary;
     WHEN ('hourly') DO;
            amt=hrlywage*min(hrs,40);
            IF hrs>40 THEN PUT 'Check Timecard';
      END; /* end of do */
      OTHERWISE PUT 'Problem Observation';
END;

concatenate a selected list of datasets

libname test 'C:\test2';

proc sql;
   select 'test.'||memname into : dlist separated BY ' '  from dictionary.tables
   where libname='TEST' and memname contains 'selection_rule';
quit;

data one;
set &dlist;
run;

cross product

in R, cross product is defined similar to inner product, but is different in other areas.

built-in multiple testing mechanism in SAS

proc multtest by Peter H. Westfall and Russell D. Wolfinger
the adjust option in proc mixed, or proc glm
exact statement from PROC NPAR1WAY

R - Good programming practice

1. Instead of x[ind ,], use x[ind, , drop = FALSE]

SAS SQL union and intersection

http://support.sas.com/documentation/cdl/en/sqlproc/62086/HTML/default/a001361224.htm

“ANYDATE” INFORMATS

http://www.lexjansen.com/wuss/2006/SAS_essentials/ESS-Carroll.pdf
“ANYDATE” INFORMATS
Sometimes you are very lucky in that the raw data you receive contains dates that are the same format. Sometimes you will encounter a messy data file where the dates are all different types of formats. The “anydate” informats are designed to allow you to read in a variety of date forms including:
• DATE, DATETIME, and TIME
• DDMMYY, MMDDYY, and YYMMDD
• JULIAN, MONYY, and YYQ

Using the anydate informats can be particularly useful when you are reading in data that contains a mixture of date forms and you want certain parts of the dates you are reading in. Anydate informats include:
• ANYDTDTE. Extracts the date portion
• ANYDTDTM. Extracts the datetime portion
• ANYDTTME. Extracts the time portion

Personalized Medicine: A Discussion

http://blogs.forbes.com/matthewherper/2011/02/25/personalized-medicine-a-discussion/

regular expression in SAS

www2.sas.com/proceedings/sugi29/265-29.pdf

R code to show UU' != I

U matrix as in SVD X=UDV' is only column orthogonal but not necessarily row orthogonal. U matrix, a N by p matrix, does not contain all the eigenvectors of XX', but only the first p vectors. X is also a N by p matrix, and XX' may have as many as N eigenvectors.

load delimited file with :

From here
If your data is longer than the default length, you need to use informats. For example, date or time values, names, and addresses can be longer than eight characters. In such cases, you either need to add an INFORMAT statement to the DATA step or add informats directly in the INPUT statement. However, when the informats are used in the INPUT statement, care must be taken to honor the function of the delimiter to prevent read errors. If you add informats in an INPUT statement, you must add a colon (:) in front of the informat, as shown in this example: