Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Mastering Internet of Things

You're reading from   Mastering Internet of Things Design and create your own IoT applications using Raspberry Pi 3

Arrow left icon
Product type Paperback
Published in Mar 2018
Publisher Packt
ISBN-13 9781788397483
Length 410 pages
Edition 1st Edition
Concepts
Arrow right icon
Author (1):
Arrow left icon
Peter Waher Peter Waher
Author Profile Icon Peter Waher
Peter Waher
Arrow right icon
View More author details
Toc

Table of Contents (18) Chapters Close

Preface 1. Preparing Our First Raspberry Pi Project 2. Creating a Sensor to Measure Ambient Light FREE CHAPTER 3. Creating an Actuator for Controlling Illumination 4. Publishing Information Using MQTT 5. Publishing Data Using HTTP 6. Creating Web Pages for Your Devices 7. Communicating More Efficiently Using CoAP 8. Interoperability 9. Social Interaction with Your Devices Using XMPP 10. The Controller 11. Product Life Cycle 12. Concentrators and Bridges 13. Using an Internet of Things Service Platform 14. IoT Harmonization 15. Security for the Internet of Things 16. Privacy 17. Other Books You May Enjoy

Calculating basic statistics

A sensor normally reports more than the measured momentary value. It also calculates basic statistics on the measured input, such as peak values. It also makes sure to store measured values regularly, to allow its users to view historical measurements. We begin by defining variables to keep track of our peak values:

private int? lastMinute = null; 
private double? minLight = null; 
private double? maxLight = null; 
private DateTime minLightAt = DateTime.MinValue; 
private DateTime maxLightAt = DateTime.MinValue; 

We then make sure to update these after having calculated a new measurement:

DateTime Timestamp = DateTime.Now; 
 
if (!this.minLight.HasValue || Light < this.minLight.Value) 
{ 
   this.minLight = Light; 
   this.minLightAt = Timestamp; 
} 
 
if (!this.maxLight.HasValue || Light > this.maxLight.Value) 
{ 
   this.maxLight = Light; ...
You have been reading a chapter from
Mastering Internet of Things
Published in: Mar 2018
Publisher: Packt
ISBN-13: 9781788397483
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at €18.99/month. Cancel anytime