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

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

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

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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