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SAS Tips I learnt whilst at Oxford. By Phil Mason. Debugging complex macros. Write code generated by macros to an external file File can’t be accessed until the SAS session has ended 6.12 - options RESERVEDB1 MPRINT ; 8 – options MFILE MPRINT ; 6.12 & 8 – filename MPRINT 'c:\macro.sas' ;

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debugging complex macros
Debugging complex macros
  • Write code generated by macros to an external file
    • File can’t be accessed until the SAS session has ended
      • 6.12 - options RESERVEDB1 MPRINT ;
      • 8 – options MFILE MPRINT ;
      • 6.12 & 8 – filename MPRINT 'c:\macro.sas' ;
    • Very useful for complex macros with many loops and multi-ampersands
    • You can then run the code generated through data step debugger
connect to yourself
Connect to yourself
  • In 8 can use MP Connect, but 6.12 …
  • Run spawner, e.g.

"C:\Program Files\SAS Institute\SAS\V8\spawner.exe" -c tcp –z

  • Run SAS code, e.g.

%let tcpsec=_prompt_;

options comamid=tcp ;

signon notebook noscript ;

  • Very useful to test out client server code on a single machine
adding operators or functions to macro language
Adding operators or functions to macro language
  • “=:” exists in data step, but not macro language
    • Create a macro which carries out required function and returns a result

%macro eq(op1,op2) ;

%if %substr(&op1,1,%length(&op2))=&op2 %then

1 ;

%else

0 ;

%mend eq ;

%if %eq(abcde,ac) %then

%put yes 1 ;

%else

%put no 1 ;

searching a catalog for text
Searching a catalog for text
  • Such a tool does not directly exist, but there is a way
  • Using PROC BUILD you can write all the source text from catalog entries to an external file
  • Then use FSLIST to view the file, or notepad, MS Word, to search it, e.g.

%macro catscan(cat,file) ;

proc build catalog=&cat batch ;

print source prtfile="&file" ;

run ;

dm 'fslist "&file"' fslist ;

%mend catscan ;

making code re startable
Making code re-startable
  • Why?
    • Robustness, saves reprocessing data
    • Save datasets & macro variables
      • %put _user_ to a dataset or file
      • Copy sashelp.vmacro to a dataset, e.g.

procsql ;

create table sasuser.macros as

select name,value from

sashelp.vmacro

where scope='GLOBAL' ;

using progress bars in base sas 1 of 2
Using Progress Bars in Base SAS (1 of 2)
  • You can produce progress bars for use in Data Steps or Macros.
    • Useful to let users know how a long macro is progressing
  • This example shows how to do so for a data step
    • A similar technique can be used from macro language using the %WINDOW and %DISPLAY statements.
  • Key points
    • Define a window shaped like a bar
    • Redisplay it each time we have some progress
    • Just change value and link to routine to update bar
using progress bars in base sas 2 of 2
Using Progress Bars in Base SAS (2 of 2)
  • Important Statements in Code
    • “Window bar ” defines progress bar display window
      • Specifies position on screen
      • Variable & colour used to display progressing bar
    • “display bar noinput” refreshes the bar display and requires no input from user to continue
windows api calls
Windows API calls
  • Use MODULE function
  • SASCBTBL definition, e.g.

routine MessageBoxA module=USER32 minarg=4 maxarg=4

stackpop=called returns=short;

arg 1 input format=pib4. byvalue;

arg 2 input format=$cstr200.;

arg 3 input format=$cstr200.;

arg 4 input format=pib4. byvalue;

  • Documentation available in Linux WINE project
    • Covers “all” APIs and is freely downloadable
module definitions partial list sampsrc pcsamp sascbtbl source
ExitWindowsGetDiskFreeSpaceAGetDriveTypeAGetModuleFileNameAGetModuleHandleAGetPrivateProfileIntAGetPrivateProfileStringAGetProfileIntAGetProfileStringAGetSystemDirectoryAGetSystemMetricsGetTempPathA ExitWindowsGetDiskFreeSpaceAGetDriveTypeAGetModuleFileNameAGetModuleHandleAGetPrivateProfileIntAGetPrivateProfileStringAGetProfileIntAGetProfileStringAGetSystemDirectoryAGetSystemMetricsGetTempPathA

GetTempFileNameAGetVersionGetVersionExAGetVolumeInformationAGetWindowsDirectoryAGetSystemInfoMessageBeepMessageBoxASwapMouseButtonWritePrivateProfileStringAWriteProfileStringAGetWin32sInfo

Module Definitions (partial list)sampsrc.pcsamp.sascbtbl.source
mixing data step sql code
Mixing data step & SQL code
  • You can have data step code in an SQL statement, e.g.

data out / view=out ;

set sasuser.houses ;

if style='CONDO' then

put 'obs=' _n_ price= ;

run ;

proc sql ;

create table more as select * from out where price >100000 ;

;quit;run;

    • This creates a dataset and writes some variable information to the log
  • Can similarly have SQL code within a data step, by using views
sort techniques based on my investigations
Sort Techniquesbased on my investigations
  • 3x data size for sort space (rule-of-thumb)
  • Compress=yes & sort can save time (-8%)
  • Tagsort, good on large datasets where key is small (e.g. -49%)
  • Almost always use Noequals (e.g. 5%)
  • Combine datastep code with sort using VIEW (e.g. -27%)
    • More on next slide …
views can move pre processing into procedures for efficiency
Views can move pre-processing into procedures for efficiency
  • Inefficient

Data test;

if … flag=1 ; run;

Proc sort data=test;table flag;run;

  • Efficient

Data test/view=test;

if … flag=1 ; run;

Proc sort data=test;table flag;run;

  • Changing data step to a view causes less I/O to be done
    • Since data is read once, IF condition applied and record fed into proc sort directly

Data read here

… and again here

Data read here, in PROC

finding secret sas options
Finding secret SAS options
  • Proc options internal ; run ;

Some options …

    • BELL Enables/disables the warning bell
    • CDE=H Display SAS System information
    • CTRYDECIMALSEPARATOR=. Country specific decimal number separator.
    • CTRYTHOUSANDSEPARATOR=, Country specific thousands number separator.
    • DEBUGLEVEL= Controls display of debug information. There are five levels (TESTING, NORMAL, DEBUG, FULLDEBUG, and DEMO).
    • ENHANCEDEDITOR Invoke the enhanced editor at SAS startup
making log available during non interactive sas sessions
Making log available during non-interactive SAS sessions
  • One of the undocumented options in SAS 6.12 which PROC OPTIONS INTERNAL reveals is:
    • $logflush … closes LOG after each line is written
  • Very useful for looking at log during non-interactive runs
  • Usually can’t see log until the SAS session finishes
put a zip in your pipe
Put a zip in your pipe
  • Pipes read live output from programs

filename testpipe pipe 'pkunzip.exe c:\temp\test -c’ ;

    • Use PKZIP to decompress archive
    • -c option sends data to console, flowing into pipe, able to be read by SAS
    • PIPE parameter is required
  • Allows processing files too large for disk
exporting using odbc setting up driver
Control Panel, 32-bit OBDC

Define a [User DSN]

[Add], [SAS], [Finish]

[Servers]

Server Name: mySAS

[Configure]

SAS Path: “c:\sas\sas.exe”

Working Directory: “c:\sas”

SAS Parameters: “-initstmt %sasodbc(mySAS) -comamid dde -icon –nolog -noautoexec”

[OK], [<<Add<<]

[Libraries],

Library Name: “mySAS”

Host File Name: “c:\temp”

[<<Add<<]

[General]

Data Source Name: “mySAS”

Description: “SAS ODBC”

[ok]

Can also define a [File DSN]...

Exporting using ODBC - setting up driver
exporting using odbc using it
Start MS Access

Make blank database

Get External Data, Input

Link Tables

File of Type: OBDC Database()

Look in: Machine Data Source

DSN Name: sas … OK

SAS should now start

SAS datasets under “c:\temp\” should appear

Select a SAS dataset … OK … OK … Open your SAS dataset

Can’t get this to work on this system (v8, win98)

Exporting using ODBC - using it
speed up your sas programs
Speed up your SAS programs
  • Use o/s commands for copying & deleting
    • They are much quicker than SAS alternatives
    • Execute o/s commands asynchronously
  • Clean up work space during job
    • Large work datasets should be deleted by you when they are no longer needed, otherwise they may take valuable space
  • Clean up memory every so often
    • Use CDE P to purge unused modules from memory
more ways to speed things up
More ways to speed things up
  • Split data into smaller bits for sorting
    • Especially if they can fit in memory
    • Saved 36% in one example
  • Sort or index on a compressed single key
  • Reduce I/O contention
    • Put work, swap and data on different physical disks where possible
mixed numeric informats
Mixed Numeric informats
  • Unquoted numerics treated as numbers
  • Quoted text treated as character
  • Useful if reading data which has mixed values, which need to be interpreted in different ways

Proc format ;

invalue mixed

‘LOW’ = -99

1-10 = 1

11-20 = 2

‘BIG’ = 99

other = 0 ;

Run ;

building long selection lists in sql
Building long selection lists in SQL
  • Even in v6 macro variables may be up to 32k long
  • Useful to store long text strings, such as variable lists
    • e.g. Can make a list of employees in one dataset to select from another

Code

where on output dataset
Where on Output dataset
  • Where clauses can be used for filtering data
  • Usually they are used with input data
  • They can be used with output data too
  • Keeping selected _type_ values
sas ole automation server
SAS OLE Automation Server
  • How did I run demos from PowerPoint?
    • PowerPoint has no scripting but can run programs
  • SASOACT.EXE
    • Controls a SAS OLE Automation Server
      • SASOACT.EXE action=Open datatype=SASFile filename=”Test.sas"
      • SASOACT.EXE action=Submit datatype=SASFile filename=”Test.sas"
      • SASOACT.EXE action=Open datatype=Data filename="Houses.sd2"
nice stuff on the web
Nice stuff on the web
  • SAS Online documentation
    • V8doc.sas.com/sashtml (SAS OnlineDoc)
  • SUGI proceedings
    • www2.sas.com/proceedings/sugi26/procced.pdf
  • Resources
    • www.sashelp.com (David Ward)
    • www.sconsig.com/sastip.htm (Charles Partridge)
  • Newsletters with tips & techniques
    • The missing semicolon – www.sys-seminar.com
    • VIEWS news – www.views-uk.org
any questions
Any questions?
  • If so, please see me afterwards since I am probably out of time.
when is 3 1 3 not 1
When is 3 * 1/3 not 1
  • Numbers within SAS are handled with floating point arithmetic

data _null_ ;

a=1/3 ;

b=3*a ;

c=1-b ;

put b= c= ;

Run ;

  • Produces

B=1 C=5.551115E-17

  • Fails due to floating point arithmetic being inexact
  • Get around it by using round function, or FUZZ in PROC FORMAT
open olap server in v8
Open OLAP Server in v8
  • EIS
  • Add MDDB, e.g. sashelp.prdmddb
  • Add olapmeta attribute
  • Run listener.scl
  • Install OOLAP server client from
    • “C:\Program Files\SAS Institute\SAS\V8\mddbserv\sasmisc\ooscl30.exe”
  • Enter EXCEL (& various other tools) & use it
versus versus
& versus && versus &&&
  • In Base SAS
    • &name refers to a macro variable called name
    • &&name is scanned twice by macro processor
    • &&&name is treated as &(&name) Code
  • If used in SCL – SAS/AF
    • &name tries to substitute SCL variable name, if it exists
      • If it does not exist, then it looks for a macro variable called name
    • &&name is useful since it doesn’t try to substitute an SCL variable even if one exists of that name, but uses the macro variable
    • &&&name works as in Base SAS
proc printto to redirect and process log
Proc Printto to redirect and process log
  • Can redirect procedure output or LOG to a catalog member or external file
  • Useful for saving log and then analysing it

proc printto log=work.test.test.log ;

run ;

proc printto print='c:\print.lst' ;

run ;

proc print data=sasuser.houses;

run ;

proc printto print=print ;

run ;

use attrib for common definitions
Use attrib for common definitions
  • To produce a PROC PRINT without any labels you can set them to null values
  • You may try the following, but it does not work since you can’t use _all_ in LABEL statements

proc print data=datatran.emptypev label noobs;

label _all_='00'x;

run;

  • You can use the ATTRIB statement which does support _ALL_ - this code works

proc print data=datatran.emptypev label noobs;

attrib _all_ label='00'x;

run;

searching program editor or log for macro variables
Searching program editor or log for macro variables
  • If you simply enter &macname in the FIND box, it will resolve &macname before looking
  • To search for the unresolved reference search for:

%nrstr(&macname)

    • %nrstr(&macname) resolves to &macname.
data step views for parsing text files to extract info
Data step views for parsing text files to extract info
  • Useful if you have regular flat file data you want to process with SAS
  • Just define a view

Data monthly / view=monthly ;

Infile ‘c:\monthly.txt’ ;

Input name $30. Address $30. ;

Run ;

  • Can use view as input to other data steps and procedures and data will always be fresh, e.g.

Proc report data=monthly ; run ;

implement parallel processing
Implement parallel processing
  • Using MP Connect in v8
  • Use Asynchronous submits in v8
  • SPDS
  • 3rd party products (best kept secrets!)
    • “Orchestrate” from Torrent Systems
      • Incredible scalability
    • “SAS Analyzer” from Ab Initio
  • Use experimental sort module in v8
    • Saspsort – works well on multi-proc machines
nice technique to split code
Nice technique to split code
  • Use views with firstobs=, obs= and where= (in v8)
  • Feed views into parallel processes such as MP Connect
some nice new v8 features
Some nice new v8 features
  • Lastword=scan(long_text,-1) ;
  • Constants
    • Pi=constant(‘pi’) ;
    • Min=constant(‘small’) ;
  • Factorials, Combinations & Permutations
    • F=fact(4) ; c=comb(8,2) ; p=perm(8,2) ;
  • If missing(var) then …
v functions
V functions
  • Varray – need a simple example of each one
  • Vformatn
  • Vinformat
  • Vname
  • Vtype
  • Vformatw
  • Vinformatdx
  • Vlength
date functions
Date functions
  • Yrdiff – need some examples
  • Datediff
  • Yymmnw
  • Yymmddxw
sas graph procedure enhancements
Sas/graph procedure enhancements
  • Hbar3d, vbar3d & pie3d
  • Html=
  • Imagemap=
  • Drivers:
    • Gif, html, webframe, gifanim, java, activex