macOS Unix time to Date String

I was working with an API today and received an authentication key, which prompted me to want to know how long it was good for. The returned expiration time was in Unix time1. I knew I could convert the Unix time format into a readable format using the date command from the macOS terminal. The […]

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Case Insensitive List (ls)

When I’m using a Unix-like terminal I don’t always remember the full name of a directory or file.  In a Unix-like world, file and directory names are case sensitive. Sometimes the system we are logged into is not always our own and therefore not customized with default settings.  In these situations the following knowledge can […]

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A Circle, Pi and Basic Formulas

I was looking around for formulas sometime back; really can not remember why, perhaps it was for a class I was taking.  I put together a diagram with the basic formulas shown below. There is a link below the image to a downloadable PDF file. Below is a link to a downloadable PDF version of […]

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Calculating System Thermal Output

The Internet abounds with information on the topic of thermal output. I’ve collected the following formulas and placed them here for my quick reference. Watts = 0.293 * BTU-Hr Watts = 3,530 * Tons BTU-Hr = 3.41 * Watts Tons = 0.000283 * Watts   For example, PacketLight PL-1000TN Optical Transport Unit PSU rated at […]

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IP Subnet Weighting Table

Converting binary to decimal/decimal to binary This is a page with two tables that helps with visualizing the conversion from binary to decimal and from decimal to binary. It’s not pretty or anything, but it does the job I think. Below link for downloading a PDF version. Weighting Table – Converting binary to decimal   […]

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