In a previous blog, I demonstrated a program and macro that could identify all numeric variables set to a specific value, such as 999. This blog discusses an immensely useful technique that allows you to perform an operation on all numeric or all character variables in a SAS data set.
When I teach my Data Cleaning course, the last topic I cover in the two-day course is SAS Integrity Constraints. I find that most of the students, who are usually quite advanced programmers, have never heard of Integrity Constraints (abbreviated ICs). I decided a short discussion on this topic would
The ancient political maxim “divide and conquer” (Lat. “dīvide et īmpera”) has been used for millennia in politics, sociology, and psychology, mainly to manipulate people. In the last two centuries, however, this principle has also been adopted by computer science. It is widely used in computer programming, primarily in computer
Wait! Don't close this window. I understand that regular expressions can be very complicated (yes, there are many books on the subject), but some basic expressions to test patterns such as zip codes or telephone numbers are not that difficult. In addition, you can sometimes use Google to search for
When SAS Add-In for Microsoft Office was first created over a decade ago, SAS programmers were told to check their skills at the door. This new product was for non-programmers only. SAS programmers were invited to contribute to the experience by packaging their code in SAS stored processes, which end
Elizabeth is courageous. Scoliosis since birth, corrective spinal surgery replaced her spine with steel, tripping on stairs permanently broke her right ankle. Then she decided to come take yoga with me. To help ease back pain & reduce hip stress, I offered options like bent legs not cross. In class
In last week's article about the Flint water crisis, I computed the 90th percentile of a small data set. Although I didn't mention it, the value that I reported is different from the the 90th percentile that is reported in Significance magazine. That is not unusual. The data only had
The little SAS program’s official name was Extract_Transform_Load_ 0314.sas. But, that name was much too formal, way too long, and did not roll off of the tongue very easily at all. So, everybody simply called her: ETL Pi. ETL Pi was conceived in a 2-hour project strategy meeting in conference
Last week I showed a timeline of living US presidents. The number of living presidents is constant during the time interval between inaugurations and deaths of presidents. The data was taken from a Wikipedia table (shown below) that shows the number of years and days between events. This article shows
When developing SAS applications, you can feed database tables into your application by using the libname access engine either by directly referring a database table, or via SAS or database views that themselves refer to one or more of the database tables. More on Automation with SAS: Let SAS write
If you're a SAS programmer, you have likely used loops in your SAS code to make life easier from time to time. In this blog post, I demonstrate a few ways you can use loops to do clever things in your graph code. Perhaps even the old dogs can learn
When developing SAS® data sets, program code and/or applications, efficiency is not always given the attention it deserves, particularly in the early phases of development. Since data sizes and system performance can affect a program and/or an application’s behavior, SAS users may want to access information about a data set’s
Even if you are a traditional SAS programmer and have nothing to do with cybersecurity, you still probably have to deal with this issue in your day-to-day work. The world has changed, and what you do as a SAS programmer is not just between you and your computer anymore. However,
I recently asked a SAS user, “Which interface do you use for SAS?” She replied, “Interface? I just install SAS and use it.” “You’re using the SAS windowing environment,” I explained, but she had no idea what I was talking about. This person is an extremely sophisticated SAS user who
Did you know that you can check a SAS macro variable to see if ODS graphics is enabled? The other day I wanted to write a SAS program that creates a graph only if ODS graphics is enabled. The solution is to check the SYSODSGRAPHICS macro variable, which is automatically
SAS formats are very useful and can be used in a myriad of creative ways. For example, you can use formats to display decimal values as a fraction. However, SAS supports so many formats that it is difficult to remember details about the format syntax, such as the default field
SAS programmers who have experience with other programming languages sometimes wonder whether the SAS language supports statements that are equivalent to the "break" and "continue" statements in other languages. The answer is yes. The LEAVE statement in the SAS DATA step is equivalent to the "break" statement. It provides a
I recently needed to solve a fun programming problem. I challenge other SAS programmers to solve it, too! The problem is easy to state: Given a long sequence of digits, can you write a program to count how many times a particular subsequence occurs? For example, if I give you
Editor’s note: This is the first in a series of articles to help current SAS programmers add SAS Viya to their analytics skillset. In this post, SAS instructors Stacey Syphus and Marc Huber introduce you to our new Introduction to SAS Viya Programming for SAS 9 Programmers video library, designed to show SAS programmers how they can
Suppose you have several discrete variables. You want to conduct a frequency analysis of these variables and print the results, but ONLY for variables that have three or more levels. In other words, you want to conditionally display some results, but you don't know which variables satisfy the condition until
After reading my article about how to use BY-group processing to run 1000 regression models, a SAS programmer asked whether it is possible to reorder the output of a BY-group analysis. The answer is yes: you can use the DOCUMENT procedure to replay a portion of your output in any
Longtime SAS programmers know that the SAS DATA step and SAS procedures are very tolerant of typographical errors. You can misspell most keywords and SAS will "guess" what you mean. For example, if you mistype "PROC" as "PRC," SAS will run the program but write a warning to the log:
What?!? You mean a period (.) isn't the only SAS numeric missing value? Well, there are 27 others: .A .B, to .Z and ._ (period underscore). Your first question might be: "Why would you need more than one missing value?" One situation where multiple missing values are useful involves survey data. Suppose
Colors are the subject of many romantic poems and songs, but there isn't much romance to be found in their hexadecimal values. With apologies to Van Morrison: ...Skipping and a jumping In the misty morning fog with Our hearts a thumpin' and you My cx662F14 eyed girl When it comes
Suppose you create a scatter plot in SAS with PROC SGPLOT. What color does PROC SGPLOT use for the markers? If you specify the GROUP= option so that markers are colored by a grouping variable, what colors are used to represent the various groups? The following scatter plot shows the
In a previous blog, Random Sampling: What's Efficient?, I discussed the efficiency of various techniques for selecting a simple random sample from a large SAS dataset. PROC SURVEYSELECT easily does the job: proc surveyselect data=large out=sample method=srs /* simple random sample */ rate=.01; /* 1% sample rate */ run; Note:
For SAS programmers, the PUT statement in the DATA step and the %PUT macro statement are useful statements that enable you to display the values of variables and macro variables, respectively. By default, the output appears in the SAS log. This article shares a few tips that help you to
How many of you have been given a SAS data set with variables such as Age, Height, and Weight and some or all of them were stored as character values instead of numeric? Probably EVERYONE! Yes, we all know how to do the old "swap and drop" (rename and convert), but
This SAS Jedi is very excited about the SAS 9.4 M4 release, which brought many wonderful gifts just in time for Christmas. So in the interest of extending the Christmas spirit, I'm going to blog about some of my favorites! I've long loved the SAS DO statement variant which allows
SAS temporary arrays are an underutilized jewel in the SAS toolbox. I find that many beginning to intermediate SAS programmers are not familiar with temporary arrays. The good news is that there is nothing complicated about them and they are very useful. First of all, what is a temporary array?
