To "benchmark" your programs, plan carefully. Optimizing efficiency with respect to one resource will often decrease efficiency with respect to some other resource. This situation can be far better managed by using the divide function to perform the calculation. You can use either the label or the attrib statement to label variables. his comment is here
The %IF statement gets evaluated when the SAS Macro program is executed, but the SAS Macro facility is only generating code that will be executed. Use the same organization for all your SAS programming. You can then sort these subsets by additional variables and concatenate the subsets to get a data set sorted by the variable you used to subset the data. Avoid confounding factors in the code, the working environment, and the SAS session.
Moving a statement out of a look to save processing time Needs improvement More efficient data new; set old; array xyz x y z; array xyzsq x2 y2 z2; do i=1 In the second case, SAS reads from disk only the three variables you intend to keep. cynthia View solution in original post percent_in_array_no_macro.png Message 4 of 7 (1,066 Views) Reply 1 Like All Replies SASKiwi Super User Posts: 2,340 Re: Divide by 0 Error in Macro Options You don’t need to read the contents into a temporary data set first.
For example, if VAR=X and Num=1, then your %IF test would seem to be asking this of the macro processor, as if the macro processor has visibility of the DATA step When we talk about "efficiency" we mean getting your job done in a way that minimizes the use of resources-computer resources or human resources. Computer resources CPU time: the time the computer’s central processing unit spends doing calculations and performing other operations. Divide By Zero Sas data men women; set in.bigdata; select (cat); when (0) output men; ** cat = 0 **; when (1) output women; ** cat = 1 **; end; run; proc sort data=men; by
Using instead of to reducing processing time Needs improvement More efficient data election; set elec94nc; if (district=1) or (district=3) or (district=4) or (district=7) or (district=8) or (district=12) then incumb = -1; Table 4. For example, if you have simple data like this:grp x1 x2 x3 x4 x5AAA 5 10 15 . 25BBB 3 . 11 13 17CCC 4 5 . 9 11and you want http://blogs.sas.com/content/iml/2015/11/04/trap-cap-division-by-zero.html Table 16.
Document your program internally Keep a blank header handy to insert at the top of every new program. So, by the time the code goes to be executed against your data, there are no macro statements left in the code. Use other techniques to emulate large sorts Sometimes a data set is too big to successfully execute proc sort. Use the “where” statement to subset data When you need to use a subset of a data set, or when you want to access part of a data set for testing
The value of your data step variables will change with every observation. No message.23 data _null_;24 x = divide(1,0);25 put x=;26 run;x=I27 28 %put NOTE: %sysfunc(divide(1,0));NOTE: I Message 7 of 7 (565 Views) Reply 0 Likes « Message Listing « Previous Topic Next Sas Floating Point Zero Divide Develop and test in stages Debugging a program is easier if you test and debug individual components of the program separately. Division By Zero Detected In Sas These statistics measure CPU time, I/O operations, and memory usage.
Also, you can plan ahead by grouping data and proc steps that require the same sorting order so that you can avoid repeating a sort that has already been done. http://darrenmanning.com/by-zero/divide-by-zero-error-in-crystal-reports.html Using the data to calculate statistics The MEANS Procedure Variable Mean N calc_result 150.0000000 1 func_result 150.0000000 1« Back to SAS Data Management« Back to all Tips and Techniques SAS TrainingCourse If you use the wrong approach, you will end up with garbled data and error messages in your log. SAS also provides information on your data sets when you use “proc contents” or “proc datasets”. Sas Divide Function
title 'Using the data to calculate statistics'; proc means data=divide_function mean n; var calc_result func_result; run; The Proc Means procedure ignores missing values. Also, if you later rearrange parts of the program your proc statements will continue to refer to the correct data set. Specify and as data set options Needs improvement More efficient data grades; set classrec; keep idnum finalex coursegr; run; data grades; set classrec (keep= idnum finalex coursegr); run; In the first weblink So generally, Macro %IF statements are NOT used to test data step variables.
You can make a copy of the data file in SAS (because SAS can read the file in a data step) and then use the copy. NOTE: 1 observations have missing values. Always review the log after submitting a job; at times you may not be able to tell from the list file output that SAS failed to complete its job.
So if you want to test whether X1 is 0, then you need a "regular" DATA step IF. Second, have a test phase to identify and quickly repair problems that show up. Coding to eliminate division by 0 error messages Needs improvement More efficient data election; set in.elect; rvotepct = 100 * (rvote/tvote); run; data election; set in.elect; if (tvote gt 0) then You can also specify keep= or drop= when you invoke a procedure; again, this lets SAS read only the variables you intend to use in the procedure rather than requiring that
If you use if-then statements to prevent SAS from trying to divide by zero, your program will run more efficiently and with fewer error messages. You can then sort these subsets by additional variables and concatenate the subsets to get a data set sorted by the variable you used to subset the data. Table 10. http://darrenmanning.com/by-zero/divide-by-zero-error-crystal-reports.html Table 17.
Coding to eliminate missing value error messages Needs improvement More efficient data election; set in.elect; sortkey = state*100 + district; run; data election; set in.elect; if (district > . ) then The exact format of the output and the statistics reported vary depending on the host system. With an in statement, SAS stops making comparisons as soon as it finds one match; with multiple or statements, SAS continues to check each expression even if one match has already Look at the following code: Table 13.
The above code is the same as: proc sort data=in.bigdata out=out.sorted; by cat age; run; Use other techniques to emulate large sorts Sometimes a data set is too big to successfully However when we use the same data to generate a calculated value it is treated as any other missing value would be, for example Proc Means. If code is written clearly, it is easier to debug, modify, and maintain. This enables anyone to see at a glance what is going on in your program.
In most cases, absolute efficiency gains will be rare. Using " " to reduce processing requirements Needs improvement More efficient data elec1980; lowerb = 5; upperb = 87; set in.election; if rvot = 0 then rvot = lowerb; else if This problem has been remedied in Stat/Transfer Version 8 and above. Using the command to reduce processing time Needs improvement More efficient data testdata; set mydata; if _n_ le 100; run; proc print data=testdata; run; ** print the first 100 obs **;
data create_data; input numerator denominator; cards; 150 1 150 0 150 .