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2月 272019
 

In this post, we continue our discussion of geography variables, the foundation of Visual Analytics Geo maps. This time we will look at Custom Coordinates.  As with any statistical graph, understanding your data is key.  But when using Custom Coordinates for geographic maps, this understanding becomes even more important.

Use the Custom Coordinate geography variable when your data does not match one of VA’s predefined geography types (see previous post, Fundamentals of SAS Visual Analytics geo maps).  For Custom coordinates, your data set must include latitude and longitude values as separate variables.   These values should be sourced from trustworthy providers and validated for accuracy prior to loading into VA.

When using Custom Coordinates, the Coordinate Space must also be considered.  The coordinate space defines the grid used to plot your data.  The underlying map is also based on a grid.  In order for your data to display correctly on a map, these grids must match.  Visual Analytics uses the World Geodetic System (WGS84) as the default coordinate space (grid).  This will work for most scenarios, including the example below.

Once you have selected a dataset and confirmed it contains the required spatial information, you can now create a Custom Geography variable.  In this example, I am using the variable Business Address from the dataset Wake_Co_Pizza.  Let’s get started.

  1. Begin by opening VA and navigate to the Data panel on the left of the application.
  2. Select the dataset and locate the variable that you wish to map. Click the down arrow to the right of the variable and chose ‘Geography’ from the Classification dropdown menu.
  3. The ‘Edit Geography Item’ window appears. Select Custom coordinates in the ‘Geography data type’ dropdown.   Three new dropdown lists appear that are specific to the Custom coordinates data type: ‘Latitude (y)’, ‘Longitude (x)’ and ‘Coordinate Space’.

When using the Custom coordinates data type, we must tell VA where to find the spatial data in our dataset.  We do this using the Latitude (y) and Longitude (x) dropdown lists.  They contain all measures from your dataset.  In this example, the variable ‘Latitude World Geodetic System’ contains our latitude values and the variable  ‘Longitude World Geodetic System’ contains our longitude values.   The ‘Coordinate Space’ dropdown defaults to World Geodetic System (WGS84) and is the correct choice for this example.

  1. Click the OK button to complete the setup once the latitude and longitude variables have been selected from their respective dropdown lists. You should see a new ‘Geography’ section in the Data panel.  The name of the variable (or its edited value) will be displayed beside a globe icon to indicate it is a geography variable.  In this case we see the variable Business Address.

 

Congratulations!  You have now created a custom geography variable and are ready to display it on a map.  To do this, simply drag it from the Data panel and drop it on the report canvas.  The auto-map feature of VA will recognize it as a geography variable and display the data as a bubble map with an OpenStreetMap background.

In this post, we created a custom geography variable using the default Coordinate Space.  Using a custom geography variable gives you the flexibility of mapping data sets that contain valid latitude and longitude values.  Next time, we will take our exploration of the geography variable one step further and explore using custom polygons in your maps.

Using Custom Coordinates for map creation in SAS Visual Analytics was published on SAS Users.

2月 082019
 

Creating a map with SAS Visual Analytics begins with the geographic variable.  The geographic variable is a special type of data variable where each item has a latitude and longitude value.  For maximum flexibility, VA supports three types of geography variables:

  1. Predefined
  2. Custom coordinates
  3. Custom polygons

This is the first in a series of posts that will discuss each type of geography variable and their creation. The predefined geography variable is the easiest and quickest way to begin and will be the focus of this post.

SAS Visual Analytics comes with nine (9) predefined geographic lookup types.  This lookup method requires that your data contains a variable matching one of these nine data types:

  • Country or Region Names – Full proper name of a country or region (ISO 3166-1)
  • Country or Region ISO 2-Letter Codes – Alpha-2 country code (ISO 3166-1)
  • Country or Region ISO Numeric Codes – Numeric-3 country code (ISO 3166-1)
  • Country or Region SAS Map ID Values – SAS ID values from MPASGFK continent data sets
  • Subdivision (State, Province) Names – Full proper name for level 2 admin regions (ISO 3166-2)
  • Subdivision (State, Province) SAS Map ID Values – SAS ID values from MAPSGFK continent data sets (Level 1)
  • US State Names – Full proper name for US State
  • US State Abbreviations – Two letter US State abbreviation
  • US Zip Codes – A 5-digit US zip code (no regions)

Once you have identified a variable in your dataset matching one of these types, you are ready to begin.  For our example map, the dataset 'Crime' and variable 'State name' will be used.  Let’s get started.

Creating a predefined geography variable in SAS Visual Analytics

  1. Begin by opening VA and navigate to the Data panel on the left of the application.
  2. Select the desired dataset and locate a variable that matches one of the predefined lookup types discussed above. Click the down arrow to the right of the variable and select ‘Geography’ from the Classification dropdown menu.
  3. The ‘Edit Geography Item’ window will open. Depending upon the type of geography variable selected, some of the options on this dialog will vary.  The 'Name' textbox is common for all types and will contain the variable selected from your dataset.  Edit this label as needed to make it more user friendly for your intended audience.
  4. The ‘Geography data type’ drop down list is where you select the desired type of geography variable.  In this example, we are using the default predefined option.
  5. Locate the 'Name or code context' dropdown list.  Select the type of predefined variable that matches the data type of the variable chosen from your data.  Once selected, VA scans your data and does an internal lookup on each data item.  This process identifies latitude and longitude values for each item of your dataset.  Lookup results are shown on the right of the window as a percentage and a thumbnail size map.  The thumbnail map displays the the first 100 matches.
  6. If there are any unmatched data items, the first 5 will be displayed.  This may provide a better understanding of your data.  In this example, it is clear from variable name as to what type should be selected (US State Names).  However, in most cases that choice will not be this obvious.  The lesson here, know your data!

Unmatched data items indicators

Once you are satisfied with the matched results, click the OK button to continue.  You should see a new section in the Data panel labeled ‘Geography’.  The name of the variable will be displayed beside a globe icon. This icon represents the geography variable and provides confirmation it was created successfully.

Icon change for geography variable

Now that the geography variable has been created, we are ready to create a map.  To do this, simply drag it from the Data panel and drop it on the VA report canvas.  The auto-map feature of VA will recognize the geography variable and create a bubble map with an OpenStreetMap background.  Congratulations!  You have just created your first map in VA.

Bubble map created with predefined geography variable

The concept of a geography variable was introduced in this post as the foundation for creating all maps in VA.  Using the predefined geography variable is the quickest way to get started with Geo maps.  In situations when the predefined type is not possible, using one of VA's custom geography types becomes necessary.  These scenarios will be discussed in future blog posts.

Fundamentals of SAS Visual Analytics geo maps was published on SAS Users.

1月 232019
 

You’re probably already familiar with Leonid Batkhan from his popular blog right here on The Learning Post. In fact, he’s one of our most engaging authors, with thousands of views and hundreds of comments. Leonid is a true SAS Sensei. He has been at SAS for nearly 25 years and [...]

The post Secrets from a SAS Expert: An Interview with Leonid Batkhan appeared first on SAS Learning Post.

12月 102018
 

When I was growing up, there were two kinds of Sundays: regular Sundays and George Sundays. George was the proprietor of a local Italian restaurant in my hometown and hosted the extended LaRusso clan for Sunday lunch every few weeks. His restaurant, appropriately named George’s, owns some of my favorite childhood memories – and some of my worst.

Every couple of months, my aunts, uncles, a baker’s dozen of cousins, and my immediate family members would take over George’s backroom and see if we could challenge the city’s noise ordinance. George would do nothing to discourage us, appearing every so often to fire balls of uncooked dough at us or ply us with more caffeine-laced sugary drinks, despite instructions to the contrary from our parents.

Invariably, though, an otherwise pleasant afternoon took a turn for the worse as we were leaving the restaurant. That was when my parents, thinking they were doing us a favor, would let us choose one item off George’s famous “candy wall.” You see, George didn’t stock just one or two different kinds of candy, he had dozens. Every different kind of chocolate bar, brand of gum, and flavor of jelly beans beckoned from George’s Candy Wall. For a 6 or 7-year-old kid, it was just too much. All these choices literally paralyzed me. Ten minutes of indecisiveness and several ultimatums later my parents would usher me out of the restaurant, usually empty-handed and crying. Even on the rare occasions when I did settle on something, I spent the rest of the afternoon lamenting my decision, thinking I left behind something that I would have enjoyed more.

When it comes to the multitude of great support and learning resources we offer new users of SAS, I often wonder if it can feel like you’re staring at George’s Candy Wall as well. While support.sas.com remains the holy grail of SAS customer support, there are so many good choices, it can sometimes be hard to know where to start. That’s why we’ve put together a new resource to make things easier for new SAS users: the SAS Starter Kit.

Need help navigating SAS Support Resources? Here’s your guide

SAS Support ResourcesThe SAS Starter Kit is the perfect place for SAS newbies to start, outlining the five essential steps to help you learn the basics, grow your skills and connect with other users from around the world.

Step 1 invites you to create a SAS profile. A profile provides you access to things like free, on-demand training, software downloads and access to our SAS Communities, where you can ask questions, get answers and connect with SAS experts from nearly every industry and around the world. You can

Step 2 is your SAS Resource Cheat Sheet. SAS Cares is your one stop listing of all the SAS resources you’ll ever need. Add it to your web favorites or print it out and add a little color to your cube. Keep this one close; it provides quick, one-click access to some of SAS’ most helpful resources.

Step 3 is designed to expand your SAS knowledge. This step introduces you to a full menu of free tutorials to binge watch, a number of free e-courses for a deeper dive and a number of other learning resources from e-books to webinars and more.

Step 4 is the perfect resource if you’re completely new to SAS or just trying something new. Our New SAS User Community is a great place to get coding help, share ideas and best practices, or just lurk! Our SAS Communities have more than 200,000 members ready to help get you unstuck or share what they know.

Finally, Step 5 introduces you to product-specific resources to help develop your skills with your specific tools. Here you’ll find the latest product news, code samples, and step-by-step instructional resources to guide you through common tasks using your product of choice.

I hope you find the SAS Starter Kit a sweet addition to your SAS toolkit.

Five essential steps to getting started with SAS

Navigating the Candy Wall of SAS Support Resources was published on SAS Users.

10月 022018
 

I often get asked for programming tips. Here, I share three of my favorite tips for beginners. Tip #1: COUNTC and CATS Functions Together The CATS function concatenates all of its arguments after it strips leading and trailing blanks. The COUNTC function counts characters. Together, they can let you operate [...]

The post Three of My Favorite Programming Tips appeared first on SAS Learning Post.

7月 172018
 

The Base SAS DATA step has been a powerful tool for many years for SAS programmers. But as data sets grow and programmers work with massively parallel processing (MPP) computing environments such as Teradata, Hadoop or the SAS High-Performance Analytics grid, the data step remains stubbornly single-threaded. Welcome DS2 – [...]

The post What DS2 can do for the DATA step appeared first on SAS Learning Post.