On the heels of the release of the popular SAS macro variable viewer from last month, I'm providing another custom task that I hope will prove just as useful. This one is a SAS options viewer, similar in concept to the OPTIONS window in SAS display manager. You can download
A few colleagues and I were exchanging short snippets of SAS code that create Christmas trees and other holiday items by using the SAS DATA step to arrange ASCII characters. For example, the following DATA step (contributed by Udo Sglavo) creates a Christmas tree with ornaments and lights: data _null_;
Rick posted a tip today about using abbreviations in the SAS program editor window (often referred to as the "enhanced editor"). Defining abbreviations is a great way to save keystrokes and re-use "templates" of code that you've squirreled away. (One of Rick's readers also picked up on the tip, and
I've been working with date-time data on a recent project, and I've come across a few SAS programs that have "opportunity for improvement" when it comes time to create reports. (Or maybe I haven't, and I contrived this entire blog post so that I could reference one of my favorite
SAS programming is taught in schools all over the world, including in high schools. Occasionally, I receive questions via my blog such as this one: Can somebody help me on this? Write a short DATA _NULL_ step to determine the largest integer you can store on your computer in 3,
Sometimes a population of individuals is modeled as a combination of subpopulations. For example, if you want to model the heights of individuals, you might first model the heights of males and females separately. The height of the population can then be modeled as a combination of the male and
The other day I encountered a SAS Knowledge Base article that shows how to count the number of missing and nonmissing values for each variable in a data set. However, the code is a complicated macro that is difficult for a beginning SAS programmer to understand. (Well, it was hard
Looping is essential to statistical programming. Whether you need to iterate over parameters in an algorithm or indices in an array, a loop is often one of the first programming constructs that a beginning programmer learns. Today is the first anniversary of this blog, which is named The DO Loop,
I previously showed how to generate random numbers in SAS by using the RAND function in the DATA step or by using the RANDGEN subroutine in SAS/IML software. These functions generate a stream of random numbers. (In statistics, the random numbers are usually a sample from a distribution such as
One of the highly visible changes in SAS 9.3 is the fact that the old LISTING destination is no longer the default destination for ODS output. Instead, the HTML destination is the default. One positive consequence of this is that ODS graphics and tables are interlaced in the output. Another
Exploring correlation between variables is an important part of exploratory data analysis. Before you start to model data, it is a good idea to visualize how variables related to one another. Zach Mayer, on his Modern Toolmaking blog, posted code that shows how to display and visualize correlations in R.
You can generate a set of random numbers in SAS that are uniformly distributed by using the RAND function in the DATA step or by using the RANDGEN subroutine in SAS/IML software. (These same functions also generate random numbers from other common distributions such as binomial and normal.) The syntax
One of the great innovations with SAS 9.3 is the focus on ODS statistical graphics. "Wait a minute," you're thinking, "weren't ODS graphics added in SAS 9.2?" Yes, that's true. But with SAS 9.3 there is even more capability: more analytical SAS procedures support the graphs, and there are more
As I was reviewing notes for my course "Data Simulation for Evaluating Statistical Methods in SAS," I realized that I haven't blogged about simulating categorical data in SAS. This article corrects that oversight. An Easy Way and a Harder Way SAS software makes it easy to sample from discrete "named"
It seems like such a simple problem: how can you reliably compute the age of someone or something? Susan lamented the subtle issues using the YRDIF function exactly 1.0356164384 years ago. Sure, you could write your own function for calculating such things, as I suggested 0.1753424658 years ago. Or you
SAS Enterprise Guide sets values for several useful SAS macro variables when it connects to a SAS session, including one macro variable, &_CLIENTPROJECTPATH, that contains the name and path of the current SAS Enterprise Guide project file. (To learn about this and other macro variables that SAS Enterprise Guide assigns,
The recent issue of InformationWeek features a Q&A session with Ken Thompson, one of the creators of the Unix operating system. (He collaborated with Dennis Ritchie, of C language fame. Since much of SAS is written in C, I daresay there are a few copies of K&R around here.) One
Jittering. To a statistician, it is more than what happens when you drink too much coffee. Jittering is the act of adding random noise to data in order to prevent overplotting in statistical graphs. Overplotting can occur when a continuous measurement is rounded to some convenient unit. This has the
In my statistical analysis of coupons article, I presented a scatter plot that includes the identity line, y=x. This post describes how to write a general program that uses the SGPLOT procedure in SAS 9.2. By a "general program," I mean that the program produces the result based on the
About a year ago (wow, has it been that long?), I posted an example program that lets you report on the contents of a SAS information map. Using my example, you can see the data items, filters, and folder structure within a given information map. Last week a reader posted
This is Part 4 of my response to Charlie Huang's interesting article titled Top 10 most powerful functions for PROC SQL. As I did for eaerlier topics, I will examine one of the "powerful" SQL functions that Charlie mentions and show how to do the same computation in SAS/IML software.
SAS-based processes are critical to many organizations, but sometimes the trickiest part of your job falls into one or both of these activities: Getting stuff from the outside world "into" SAS. (Once it's in SAS, as many of you know, the world is your oyster.) Getting the output of your
When Charlie H. posted an interesting article titled "Top 10 most powerful functions for PROC SQL," there was one item on his list that was unfamiliar: the COALESCE function. (Edit: Charlie's blog no longer exists. The article used to be available at http://www.sasanalysis.com/2011/01/top-10-most-powerful-functions-for-proc.html) Ever since I posted my first response,
It's a simple task to use SAS to compute the number of weekdays between two dates. You can use the INTCK function with the WEEKDAY interval to come up with that number. diff = intck('WEEKDAY', start_date, end_date); If you want to compute the number of working days between two dates,
Last week I showed how to create a funnel plot in SAS. A funnel plot enables you to compare the mean values (or rates, or proportions) of many groups to some other value. The group means are often compared to the overall mean, but they could also be compared to
This morning I delivered a talk to visiting high school students at the SAS campus. The topic: using SAS to analyze Twitter content. Being teenagers, high school students are well familiar with Twitter. But this batch of students was also very familiar with SAS, as they all have taken SAS
String comparisons in SAS software are case-sensitive. For example, the uppercase letter "F" and lowercase letter "f" are treated as unique characters. When these two letters represent the same condition (for example, a female patient), the strings need to be handled in a case-insensitive manner, and a SAS programmer might
The Flowing Data blog posted some data about how much TV actors get paid per episode. About a dozen folks have created various visualizations of the data (see the comments in the Flowing Data blog), several of them very glitzy and fancy. One variable in the data is a categorical
Millions of Americans will be gathering around the television this Sunday to watch Super Bowl XLV. They'll gather in bars and private homes, prepare billions of calories worth of snacks, and root for their favorite teams. But if you're looking for an alternate form of entertainment, why not watch "New
As Cat Truxillo points out in her recent blog post, some SAS procedures require data to be in a "long" (as opposed to "wide") format. Cat uses a DATA step to convert the data from wide to long format. Although there is nothing wrong with this approach, I prefer to
