Alvin Alexander | Java, Scala, Unix, Perl, Mac OS X

This page contains a large collection of examples of how to use the Scala Map class, including most of the methods that are available on a Vector. (Currently well over 100 examples.)

With the fireweed blooming in Alaska, summer will soon be yielding to fall and winter.

Fireweed blooming in Alaska (and winter coming)

Enjoyed Cowboys & Aliens at Wasilla’s fancy new stadium seating movie theater. How strange to walk out of a theater and into a valley of fireweed surrounded by misty mountains.

(A Facebook post from Wasilla, Alaska, August 9, 2011.)

Maybe the sun’s light will be dim
And it won’t matter anyhow
If morning’s echo says we’ve sinned
It was what I wanted now
And if we’re victims of the night
I won’t be blinded by the light.

~ Judy Kay “Juice” Newton, “Angel of the Morning

I’m a fan of Domata Peko of the Denver Broncos. This video helps to show why I like him, he seems like a bundle of happy energy, a real positive force. (There’s also that whole war battle thing, too.)

If you happen to walk down the right side street in Santa Fe, New Mexico, you’ll come across this Burro Alley painting on a wall.

Burro Alley painting (Santa Fe, New Mexico)

“And that’s one reason we like to believe in genius. It gives us an excuse for being lazy.”

~ Paul Graham, What You Wish You’d Known

Linux/Unix FAQ: Can you share some Linux find command examples?

Sure. The Unix/Linux find command is very powerful. It can search the entire filesystem to find files and directories according to the search criteria you specify. Besides using the find command to locate files, you can also execute other Linux commands (grep, mv, rm, etc.) on the files and directories you find, which makes find extremely powerful. 

Six weeks after colectomy surgery I’m able to eat some solid foods for the first time since October, 2017. I also hope to start practicing yoga again in a few weeks.

Table of Contents1 - macOS: crontab, launchd, and launchctl2 - Running a simple command every minute with Mac launchd3 - 1) Move to the $HOME/Library/LaunchAgents directory4 - 2) Create a Mac plist file to describe your job5 - 3) Tell MacOS about your Mac plist launchd file6 - 4) How Mac launchd works with system reboots7 - An important note about root and sudo access8 - MacOS launchd, launchctl, and plist resources9 - MacOS startup jobs: cron and crontab, launchd and launchctl

MacOS crontab FAQ: How do I run a Unix job (or shell script) through the MacOS crontab facility? I keep trying to edit my Mac crontab file, but my Mac won't save my crontab changes, or run my program.

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macOS: crontab, launchd, and launchctl

Way back when (~2012-2014), I found that the Mac crontab command was deprecated on MacOS, and the Apple documentation encouraged you to use their launchd facility. Here’s a blurb from Apple's crontab man page:

“Darwin note: Although cron(8) and crontab(5) are officially supported under Darwin, their functionality has been absorbed into launchd(8), which provides a more flexible way of automatically executing commands. See launchctl(1) for more information.”

Summary: How to create a public and private key pair to use ssh and scp without using a password, which lets you automate a remote server backup process.

Over the last two years I've ended up creating a large collection of websites and web applications on a variety of Linux servers that are hosted with different companies like GoDaddy and A2 Hosting. I recently embarked on a mission to automate the backup processes for all these sites, and as a result of this effort, I thought I'd share what I've learned here.

For an adult with memory problems (dementia) we’re trying these “You Paint It” kits. The one shown is a collection of forest animals, and they also have dogs and cats, some sort of horse-like characters, and emoji figurines.

You Paint It plaster figurines

I woke up on the left side of a king size bed this morning. It wasn’t my bed, but I was blanketed in a thick, soft comforter, which felt wonderful. I looked around briefly. Wherever I was, the room seemed very nice. It was light outside.

I’m surprised when many functional programmers feel the need to say something bad about Scala. As a community, that makes them seem like a bunch of people who aren’t very nice. There are things I don’t like about Haskell, F#, Lisp, Scala, Kotlin, Go, Perl, PHP, Python, C, C++, etc., but I don’t feel the need to take pot shots at any languages or individuals.

This page is a work in progress, but if you need to create a secondary class constructor in Kotlin, I hope it’s helpful.

I haven’t read it yet, but I’m told that Cats, Cubits, and Teleportation is a clear description of quantum computing.

This is the amino acids supplement chart from the excellent book by Julia Ross, The Diet Cure. With this chart you look at the first two columns to find whatever “deficiency” problems you may be having, then look for the amino acid supplement(s) that are known to help with those problems.

I originally learned about this when my thyroid was failing in 2011. L-tyrosine was a major help in living through that problem.

The Diet Cure: Amino acids supplement chart

If you’re into puzzles and games of math and logic, The Riddler looks like it will be a good book when it comes out.

The Riddler - a book of puzzles, math, and logic games

I’ve been looking for a way to make Functional Programming, Simplified smaller, but haven’t yet found a way to do that while keeping all the essential information in it. But IMHO, it’s still a heck of a lot easier than reading all of these books on the right:

Once upon a time I lived in Alabama and had a 52-mile daily drive to work at a NASA facility in Mississippi, which gave me a lot of time to think. At one point on the trip you pass eight churches in ten miles — a friend referred to that stretch as “The highway to heaven” — and seeing weddings, funerals, and other gatherings at those churches led me to think about life, death, and spirituality.

I was very aware that I was a spiritual being since I was 16, but despite that I never cared for a religious framework; every church I’d ever been to seemed superficial compared to what I had experienced. That being said, I always thought prayer was a good thing — it helped to create a proper state of mind — so I tried to come up my own prayer, something I could believe in.

One idea I came up with was to write some sort of prayer that would honor the ancestors that led to my life on Earth. But, I thought, a problem with this approach was that my ancestors weren’t all that honorable. My mom is probably the nicest person in the world, so there was no problem there, but without getting into details, my dad, my grandparents, aunts and uncles ... there weren’t many people I was concerned about honoring.