Using a raspberry pi with a microphone to hear an audio alarm using FFT in python

Benjamin Chodroff

If your smoke alarm or, in my case, water alarm goes off you want to know right away – even if you are currently half way across the world traveling in China. I run a fish tank. I take many precautions but you really can’t be too safe. I bought a set of Honeywell water sensors which I highly recommend. Sadly, this particular alarm is not IoT enabled. In fact, last I checked all the IoT alarm systems were terribly reviewed and overpriced. Hopefully that gets fixed soon. Until then, I needed to make do with what I had.

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Getting started with LoRa using a LoPy for IoT

Benjamin Chodroff
LoPy

When a colleague first told me about LoRa, I was skeptical that it was even real. I can use a small handheld device to transmit messages up to 40km to another device for free? It sounds too good to be true, but it’s real. Of course, there is a catch – less bandwidth. But who cares? If all I need to send from my IoT device is perhaps some longitude, latitude, and basic sensor data — LoRa is a great technology.

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Comparing diamonds with linear regressions using python R in jupyter notebooks

Benjamin Chodroff

Buying a ring is a big decision. You have the whole “are they the one” decision. I can’t help you with that. Then you have the reality that this could likely be the first major financial decision that will impact both of you. Wouldn’t it be nice if you could save hundreds or even thousands of dollars?

I am not here to convince you to avoid buying a diamond (thanks, De Beers). Instead, I am going to show you a basic statistical programming technique with python and R known as a “linear regression model.” I will use a jupyter notebook to execute data analysis so you can see step by step how it works.

You might be able to use this to shop smartly by allowing you to compare an actual cost in store to a predicted price. My wife and I built and used this code in 2013 while engagement ring shopping together. Hope it helps others!

Let’s get started!

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Learning to screen scrape data using Google Chrome and curl

Benjamin Chodroff
Pricescope.com Results

Screen scraping can be effective at getting free data very quickly. When attempting to screen scrape large amounts of data, I often use Google Chrome’s “Developer Tools” to obtain the steps necessary to recreate a web request. Here is an example process I used to screen scrape data from pricescope.com which contains a database about diamonds for sale online. I will use this data in an upcoming post on how to build statistical models.

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Using Apache NiFi on macOS to connect to IBM Bluemix Watson IoT using MQTT to IoT

Benjamin Chodroff
ConsumeMQTT NiFi Queue

I tried out Apache NiFi and liked how easy it was to act as an integration to bridge disparate Internet of Things systems together. I have previously tried NodeRED which I still highly recommend. Where I see NiFi exceeds is its ability to track each communication throughout the chain of custody.  This concept is marketed as provenance and tracks the exact data transformation that occurs from input to output.

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Backup and Restore Boot Camp on a new mac for free

Benjamin Chodroff
bootcamp backup partition

If you want to move your Windows 10 Boot Camp partition from one Mac to another, or simply to make a backup, then I hope this guide will help you! Please start by taking backups of all your data – both Mac and your Windows installation – and store these backups some place safe while you work. We will use open source and other utilities already installed on your mac – dd, hdiutil, and Disk Utility.

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