Search Results: ellipse (50)

Learn SAS
Rick Wicklin 0
Break a sentence into words in SAS

Two of my favorite string-manipulation functions in the SAS DATA step are the COUNTW function and the SCAN function. The COUNTW function counts the number of words in a long string of text. Here "word" means a substring that is delimited by special characters, such as a space character, a

Data Visualization
Sanjay Matange 0
Polar Graph - Wind Rose

Last week I posted an article on displaying polar graph using SAS.  When the measured data (R, Theta) are in the polar coordinates as radius and angle, then this data can be easily transformed into the XY space using the simple transform shown below.     x=r*cos(theta * PI / 180);     y=r*sin(theta * PI

Data Visualization
Sanjay Matange 0
Polar Graph

There are many situations where it is beneficial to display the data using a polar graph.  Often your data may contain directional information.  Or, the data may be cyclic in nature, with information over time by weeks, or years.  The simple solution is to display the directional or time data

Data Visualization
Sanjay Matange 0
Proportional Euler Diagram

The topic of VENN diagrams had come up a while ago.  At that time, I thought it may be interesting to build a proportional VENN diagram.  But, reading up on VENN Diagrams, I learned that VENN diagrams represent all intersections of N sets, regardless of whether there are actually any observations in one

Martin Demel 0
Eine Ära geht zu Ende – Oberbürgermeisterwahlen in der Stadt mit Herz

Wahlen sind ein beliebtes, aber auch kontrovers diskutiertes Thema. Es erregt Gemüter, liefert Diskussionsstoff und polarisiert Meinungen. Insbesondere Präsidentschaftswahlen oder Parlamentswahlen sind für Medien wie Volk gleichermaßen von großem Interesse. Aber auch Kommunalwahlen haben durchaus ihren Reiz. Vor allem wenn sie eine nahezu historische Bedeutung haben und eine Ära zu

Rick Wicklin 0
Compute a contour (level curve) in SAS

Like many other computer packages, SAS can produce a contour plot that shows the level sets of a function of two variables. For example, I've previously written blogs that use contour plots to visualize the bivariate normal density function and to visualize the cumulative normal distribution function. However, sometimes you

Data Visualization
Sanjay Matange 0
Simpler is better

A recent article in the SAS and R blog was about current winter temperatures in Albany, NY.  The temperature data for the recent winter (Dec 2011 - Mar 2012) was plotted on a polar graph. Robert Allison posted an article on displaying the same data as a Polar Graph using SAS/GRAPH .  Here is his

Data Visualization
Dan Heath 0
Roses are red, violets are blue...

This classic start to a romantic poem assumes that the correct colors are always assigned to the correct flowers; but, for those who create graphs for reports, consistent color assignment can be more of a challenge than an assumption. This challenge is particularly true for the display of group values.

Advanced Analytics
Rick Wicklin 0
What is Mahalanobis distance?

I previously described how to use Mahalanobis distance to find outliers in multivariate data. This article takes a closer look at Mahalanobis distance. A subsequent article will describe how you can compute Mahalanobis distance. Distance in standard units In statistics, we sometimes measure "nearness" or "farness" in terms of the

Advanced Analytics
Rick Wicklin 0
Use the Cholesky transformation to correlate and uncorrelate variables

A variance-covariance matrix expresses linear relationships between variables. Given the covariances between variables, did you know that you can write down an invertible linear transformation that "uncorrelates" the variables? Conversely, you can transform a set of uncorrelated variables into variables with given covariances. The transformation that works this magic is

Data Visualization
Sanjay Matange 0
SGPLOT procedure - the basics

In this blog we will discuss many aspects of the SG Procedures.  This article will cover some basic features and workings of the SGPLOT procedure to establish a baseline. The single-cell graph is the work horse for data visualization.  From the simple bar chart to the complex patient profiles for clinical

Rick Wicklin 0
Multithreaded = more productive

NOTE: SAS stopped shipping the SAS/IML Studio interface in 2018. It is no longer supported, so this article is no longer relevant. When I write SAS/IML programs, I usually do my development in the SAS/IML Studio environment. Why? There are many reasons, but the one that I will discuss today