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Showing posts from October, 2008

How to determine whether a numeric or character value exists within a group of variables

Using the IN operator to determine whether a numeric or character value exists within a group of variables When trying to determine whether a specific value exists within a group of variables, a common approach is to associate the variables with an ARRAY and then use a DO loop to loop through every element or variable in the ARRAY. As an example, here is a segment of code: array my_array[*] var1 - var10; do i = 1 to dim (my_array); if some_value = my_array[ i ] then found = 'Yes' ; end ; A more efficient alternative is to use the IN operator with the name of the ARRAY and avoid using the DO loop. This can be done with both numeric ARRAYS as well as character ARRAYS. Here is a code segment: array my_array[*] var1 - var10; if some_value IN my_array then found = ' Yes '; source: http://support.sas.com/kb/33/227.html

How to convert a SAS date to a character variable

/***************************************************************************//* Title: Convert a SAS date to a character variable *// * *//* Goal: Use the PUT function to create a character variable from *//* a SAS date. *//* *//***************************************************************************/ data one; input sasdate :mmddyy6.; datalines; 010199; run; data two; set one; chardate=put(sasdate,mmddyy6.); run; /* RESULTS */ Obs sasdate chardate 1 14245 010199 Source: ftp://ftp.sas.com/techsup/download/sample/datastep/convertchar.html

How to convert a character variable that represents a date into a SAS date

Convert a character variable that represents a date into a SAS date Use the INPUT function to convert a character value that represents a date into a SAS date value. Data one; input chardate1 :$6. chardate2 :$9. chardate3 $10. chardate4 :$9.; datalines; 010199 31dec1999 21/09/2005 5/9/2005; Run; /* Use the INPUT function to convert a character value that represents a date *//* into a SAS date value. Choose the second parameter to the INPUT function *//* based upon what the current character value looks like. Use a FORMAT *//* statement to apply the date format you want when you are done. *//* *//* Note: If you are in SAS 9.0 or above, you may prefer using the ANYDTDTEw. *//* Informat as the second argument to the INPUT function. ANYDTDTEw. *//* can read multiple date layouts. Refer to the SAS Language Reference, *//* Dictionary under INFORMATS for more information. */ data two; set one; sasdate1=input(chardate1,mmddyy6.); sasdate2=input(chardate2,date9.); sasdate3=input(chardate3,ddmmy...

LAG Function: How to obtain information from previous observation(s)

Often times SAS® programmers need to retain the value of a variable in the current observation to the next observation. The LAG function  can be very helpful here. A LAGn (n=1-100) function returns the value of the nth previous execution of the function. It is easy to assume that the LAGn functions return values of the nth previous observation. Using the LAG function to obtain information from previous observation(s) **********************************************************; /* Sample 1: Create a single lag of one variable */ data one; input x; lagonce= lag (x); datalines ; 1 2 3 4 5 ; proc print data=one; title 'Sample1: Single lag of one variable' ; run ; ***************************************************************; /* Sample 2: Create multiple lags of one variable */ data two; input x; lag1 = lag (x); lag2= lag2 (x); datalines ; 1 2 3 4 5 ; proc print data=two; title 'Sample 2: Multiple lags of one variable' ; run ; ...

IMPLEMENTATION OF CDISC STANDARDS

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IMPLEMENTATION OF CDISC STANDARDS Presented By Sandeep Raj Juneja, ASG Inc.... CDISC accomplishments and Strategy CDISC an d Standards for Clinical Research by Rebecca D.Kush, Ph.D, Founder & President,CDISC CDISC SDTM and related initativies CDISC submission standard : CDISC SDTM_Basics Supporting Th e CDISC Standards By Mark Lambrecht,PhD, Principal Consultant,Life Sciences,SAS Case Report Tabulation Data Definition Specification (define.xml) CDISC Study Data Tabulation Model SDTM Implementation Guide V3.1.1 http://www.cdisc.org/models/sdtm/v1.1/index.html Clinical Data Integration: SAS Clinical Data Integration By Dave Smith, SAS UK Industry Standards for the electronic submission of Data to the FDA by Michael A.Walega CDISC SDTM Basics