codekitchen

There have been some subreddits for other programming languages playing with the One Billion Row Challenge in languages other than Java. I've been wanting to try out Ractors for a while, and this seemed like a good opportunity -- it's a straightforward problem (read a CSV with 1 billion rows, about 13GB, and do some basic aggregation), but it's classic map/reduce so still a problem where true parallelism should speed things up.

I'm using Ruby 3.3. All measurements are on my M1 Macbook Air, just using MacOS /usr/bin/time -hl.

The baseline Java implementation takes 3:05 on my machine, using 252 MB.

[My straightforward single-th

I wanted to go beyond just the specially-crafted input files we were given for this problem, it was a ton of fun figuring out how to make a simulation of this size tractable. Day 21 is closely related to Conway's Game of Life and other similar cellular automaton. I initially thought that was where part 2 was going to lead us, before realizing it was more of a puzzle in deciphering what was special about the input.

I've only ever been casually aware of Conway's Game of Life, but after doing some reading I ended up implementing a version of the HashLife algorithm used in some simulators. The algorithm has ways to compress both time and space, allowing s

I am an avid mountain biker looking to pick up a new e-bike not for the trails but for errands, commuting, and riding around downtown. I live in the mountains but I don’t mind climbing on a bike, so I think I’d be fine with a smaller motor that just helps take the edge off climbing 1000 vert feet home from the grocery store. My problem is finding something I’ll enjoy riding around.

I bought a Ride1up 500 a couple years ago. I’m sure it’s a great bike for many but I find myself not riding it often because I just don’t enjoy it much — it feels like dead weight under me, it’s no fun to throw around or hit curbs. It’s designed to be stable, not playful.

I could just buy an e-MTB but I don’t n

We have had CenturyLink fiber for 3-4 years now with zero issues. But suddenly on Wednesday I got an email that our payment failed, though nothing has changed with my card. Trying to fix this has been hugely frustrating.

Absolutely everything on the CL site related to billing seems to throw errors. I did a support chat and paid through some separate janky form they sent me to, but that payment still doesn’t show up on the site 2 days later. I’m still getting scary messages saying my internet will be suspended today. Support claims I should just ignore them, I won’t be suspended. What in the world is going on with CL’s billing systems.

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[New Lennox system with heat pump and 2 zones. I called the installer back out because the HP wasn't functioning and it was always going to aux heat. He said his Lennox rep told him to use a jumper here in this situation, which I didn't know enough to disagree with. But I found this in the iHarmony manual after he left, It has a big warning: \"Heat Pump Systems Only: Do not use jumper for pressure switch terminals at the damper control module. System will not function properly without pressure switch installed.\" Am I right in thinking this fix will cause problems later? How do I approach this?](https://preview.redd.it/4soh8nmf5tqb1.jpg?width=4032&format=pjpg&auto=webp&s=d283a843

We are adding on to our house on the northeast side. The tan rooms are new/modified, the white is existing space we aren't planning to modify. The goal in the basement is to have two bedrooms, a living room, and ideally some storage space. There are a couple constraints that are making this really difficult for me to wrap my head around.

https://preview.redd.it/8pindj812mfb1.png?width=1275&format=png&auto=webp&s=934c3302fe414c0fb40132d98f9e8dc47c06f34b

1. No new windows on the north side, it's too close to the property line.
2. We have to retain half of the original foundation wall that runs west of the new bedrooms, otherwise the beam spanning the cutout would be too large for the ceiling

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https://preview.redd.it/ckz8bd94ylfb1.png?width=1275&format=png&auto=webp&s=9779aa3b73c691945c876e3998e35af98299844c

We are adding on to our house on the northeast side. The tan rooms are new/modified, the white is existing space we aren't planning to modify. The goal in the basement is to have two bedrooms, a living room, and ideally some storage space. There are a couple constraints that are making this really difficult for me to wrap my head around:

1. No new windows on the north side, it's too close to the property line.
2. We have to retain half of the original foundation wall that runs west of the new bedrooms, otherwise the beam spanning the cutout would be too large for t