SAS formats are flexible, dynamic, and have many uses. For example, you can use formats to count missing values and to change the order of a categorical variable in a table or plot. Did you know that you can also use SAS formats to recode a variable or to bin
I'm addicted to you. You're a hard habit to break. Such a hard habit to break. — Chicago, "Hard Habit To Break" Habits are hard to break. For more than 20 years I've been putting semicolons at the end of programming statements in SAS, C/C++, and Java/Javascript. But lately I've been
I've been working on a SAS program that can add content to the SAS Support Communities (more on that in a future post). Despite my 20+ years of SAS experience, there are a lot of SAS programming tricks that I don't know. Or that I use so infrequently that I
One thing that we have a lot of at SAS: installations of SAS software that we can run. I have SAS for Windows on my laptop, and I have access to many centralized instances of SAS that run on Linux and Windows servers. (I also have access to mainframe SAS,
Every beginning SAS programmer learns the simple IF-THEN/ELSE statement for conditional processing in the SAS DATA step. The basic If-THEN statement handles two cases: if a condition is true, the program does one thing, otherwise the program does something else. Of course, you can handle more cases by using multiple
The one thing, above all others, that I wish PROC REPORT could do is know which observations from my data set that I want kept together on a single page of non-Listing output. This is problematic for two reasons. 1. PROC REPORT cannot read my mind! 2. PROC REPORT does
Last week I analyzed 12 million records of taxi cab transactions in New York City. As part of that analysis, I used a DATA step view to create a new variable, which was the ratio of the tip amount to the fare amount. A novice SAS programmer told me that
Have you ever used SAS to produce reports for publishing? Have you ever thought of or been told about suppressing data in such reports? Why do we need to suppress (in the sense of withholding, concealing, obscuring or hiding) data in published reports? The reason is simple - in order
I know what you're thinking: two "Boaty McBoatface" articles within two weeks? And we're past April Fool's Day? But since I posted my original analysis about the "Name our ship" phenomenon that's happening in the UK right now, a new contender has appeared: Poppy-Mai. The cause of Poppy-Mai, a critically
In a voting contest, is it possible for a huge population to get behind a ridiculous candidate with such force that no other contestant can possibly catch up? The answer is: Yes. Just ask the folks at NERC, the environmental research organization in the UK. They are commissioning a new
In previous articles, I've shared tips about how you can work with SAS and ZIP files without requiring an external tool like WinZip, gzip, or 7-Zip. I've covered: How to create ZIP files with ODS PACKAGE ZIP (available since SAS 9.2) How to "unzip" and read ZIP files using FILENAME
One of the first things SAS programmers learn is that SAS data sets can be specified in two ways. You can use a two-level name such as "sashelp.class" which uses a SAS libref (SASHELP) and a member name (CLASS) to specify the location of the data set. Alternatively, you can
A dummy variable (also known as indicator variable) is a numeric variable that indicates the presence or absence of some level of a categorical variable. The word "dummy" does not imply that these variables are not smart. Rather, dummy variables serve as a substitute or a proxy for a categorical
TL;DR The next time that you find yourself writing a PROC SORT step, verify that you're working with the SAS Base engine and not a database. If your data is in a database, skip the SORT! The details: When to skip the PROC SORT step Many SAS procedures allow you
Novice SAS programmers quickly learn the advantages of using PROC SORT to sort data, followed by a BY-group analysis of the sorted data. A typical example is to analyze demographic data by state or by ZIP code. A BY statement enables you to produce multiple analyses from a single procedure
Parameters in SAS procedures are specified a list of values that you manually type into the procedure syntax. For example, if you want to specify a list of percentile values in PROC UNIVARIATE, you need to type the values into the PCTLPTS= option as follows: proc univariate data=sashelp.cars noprint; var
I began 2016 by compiling a list of popular articles from my blog in 2015. This "People's Choice" list contains many interesting articles, but some of my personal favorites did not make the list. Today I present the "Editor's Choice" list of articles that deserve a second look. I've grouped
The most recent development environment for SAS programmers is SAS Studio, which is a browser-based application. The free SAS University Edition, which includes SAS/IML software, also uses SAS Studio as a development environment. SAS Studio has a special mode for programmers who use interactive procedures such as PROC IML. (Recall
Last week my colleague Chris Hemedinger published a blog post that described how to use the ODS LAYOUT GRIDDED statement to arrange tables and graphs in a panel. The statement was introduced in SAS 9.4m1 (December 2013). Gridded layout is supported for HTML, POWERPOINT, and the PRINTER family of destinations
The ODS statement controls most aspects of how SAS creates your output results. You use it to specify the destination type (HTML, PDF, RTF, EXCEL or something else), as well as the details of those destinations: file paths, appearance styles, graphics behaviors, and more. The most common use pattern is
Sometimes you are writing a program that needs to find out whether a particular SAS product (like SAS/ETS, SAS/QC, or SAS/OR) is licensed. I was reminded of this fact when I wrote last week's blog post about how to create a map with PROC SGPLOT. Although the SGPLOT procedure is
How much does this big pumpkin weigh? One of the cafeterias at SAS invited patrons to post their guesses on an internal social network at SAS. There was no prize for the correct guess; it was just a fun Halloween-week activity. I recognized this as an opportunity to apply the
In SAS, the DATA step and PROC SQL support mnemonic logical operators. The Boolean operators AND, OR, and NOT are used for evaluating logical expressions. The comparison operators are EQ (equal), NE (not equal), GT (greater than), LT (less than), GE (greater than or equal), and LE (less than or
I've previously written about how to generate a sequence of evenly spaced points in an interval. Evenly spaced data is useful for scoring a regression model on an interval. In the previous articles the endpoints of the interval were hard-coded. However, it is common to want to evaluate a function
Statistical programmers often have to use the results from one SAS procedure as the input to another SAS procedure. Because ODS enables you to you to create a SAS data set from any ODS table or graph, it is easy to obtain a data set that contains the value of
Our new book, Exercises and Projects for The Little SAS® Book Fifth Edition, includes a variety of exercises to help people learn SAS programming. Rebecca Ottesen, Lora Delwiche and I designed this book so that it can be used either in a classroom setting or by individual readers working alone.
Last week, SAS released the 14.1 version of its analytics products, which are shipped as part of the third maintenance release of 9.4. If you run SAS/IML programs from a 64-bit Windows PC, you might be interested to know that you can now create matrices with about 231 ≈ 2
Equations that involve trigonometric functions can have infinitely many solutions. For example, the solution to the equation tan(θ)=1 is θ = π/4 + kπ, where k is any integer. In order to obtain a unique solution to the equation, we define the "arc" functions: inverse trigonometric functions that return a
When reading a text file (common extensions: TXT, DAT; or, for the adventurous: HTML) with the DATA STEP, you should always view several lines from the text file, and compare to the record layout, before completing the INPUT statement. There are many ways to view a text file. I use
I previously wrote about the best way to suppress output from SAS procedures. Suppressing output is necessary in simulation and bootstrap analyses, and it is useful in other contexts as well. In my previous article, I wrote, "many programmers use ODS _ALL_ CLOSE as a way to suppress output, but
