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Hi, I’m Bradley Ashby and I’m a Project Manager with our connectivity group here at Wolfram Research. I worked on the Data Drop project and I want to present a quick example to demonstrate how easy it is now to get data into the Wolfram Language using Data Drop. The Wolfram Data Drop is a universal data accumulator, which makes it incredibly simple to store data in the Wolfram Cloud. Data is primarily added via API calls though there are many other methods available and even more on the way The data is then stored in data bins where each entry is time stamped as it comes in. You can also set up a data bin so that it knows what types of data it will be storing. These data semantics then will then convert incoming data into entities or quantities with units as appropriate, making your data more valuable. Now, I’d call myself a novice when it comes to programming in any language so this example is definitely an “if I can do it, you can do it” sort of situation. We also have this Quick Reference set up to help familiarize new users with Data Drop’s functionality. A while ago there was a post on the Wolfram Community site about how to use an Android app called “Tasker” to send data to the Wolfram Data Drop. I thought this was a pretty keen idea—“Tasker” is a highly programmable app that provides access to the treasure trove of data that is collected by smartphones; most importantly for Data Drop it can send API requests. I set my own phone to start logging all sorts of data just to see what we had to work with. The Community post here has details on how to set this up but I have a screen shot of the data that I’ve been collecting on my own phone. So next I set up a data bin with the appropriate data semantics for these values that I will be collecting. This is pretty similar to how you define parameters for an API function as an association of keys and interpreters. You’ll notice that “restricted structured quantity” sees heavy use here. It simply adds the given units to the values it receives. For this example, I’m going to pull out the location and wifi connection information. My plan is to make a map of all the locations around time where I can connect to a wifi network. That way, if my mobile data plan runs out or I need to transfer a large file, it’ll be easy to map out my options. I happen to know in this case that I have enough data in the most recent 400 entries to create a decent map so I’m going to only access the entries I need to save some processing time. We just execute this line here and it will pull up the data bin that we need. I’m looking specifically for times where I’ve been successfully connected to the wifi. “Tasker” sends this with a string with a bunch of angle brackets here, “connection”, and “normal” of a data bin returns the list of entries with each entry as an association of key value pairs that were received. So then we select the entries that were returned with the correct string. Now I just need to pull out the locations—there’s our list of geopositions. And then I plot them on a map with “GeoListPlot”. And there we go. Now I know wherever I am in town, there’s a wifi spot nearby that I can run to. Now since Data Drop is accessible from the Wolfram Cloud, the next natural step is to create an API that I can call on the go. I just combine the above steps and “CloudDeploy”. Now I can just visit this URL whenever I need to. This example can be taken even further by automatically calculating which location is closest. I’ll leave that as an exercise for you though. I decided to use “Tasker” to fuel this example because it illustrates two strong points of Data Drop. One, with Data Drop, all it takes to get data into the Wolfram Language is a simple API call. If you’re making a do-it-yourself application for personal use or one for commercial reasons it’s very simple to start collecting data—if you can make a post or a request, you’re ready to start. I used an Android app for this but you could build websites, apps, or directly into a device. And then second, by defining data semantics for my data bin, I not only had access to the data from a smartphone but I was able to give it more value as it came in. The latitude and longitude coordinates, for example, were just sent as strings before they were interpreted into geopositions by the Wolfram Language and now they are ready to be used immediately by all of the geofunctions that are already built in. I hope you’ve enjoyed this quick demonstration of the Wolfram Data Drop and some of the utilities it opens up even if for beginners like me. If you find any other examples or have any questions, please post them to the Wolfram Community site; I’d be excited to see them. Thank you. Up next we have Cliff Hastings with an overview of Mathematica Online.

Video Details

Duration: 5 minutes and 20 seconds
Language: English
License: Dotsub - Standard License
Genre: None
Views: 26
Posted by: wolfram on May 15, 2015


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