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lopsidedBrain | 5 years ago | on: From Vector Spaces to Periodic Functions (2019)

It is partly historical notoriety. It allows one to prove certain statements that seem counter-intuitive. So proofs that employ it can often be viewed with some skepticism.

Moreover, this axiom is _independent_ of the other axioms in ZFC. It is in fact possible to have entirely self-consistent "worlds" of mathematics, ones where axiom of choice is true, and ones where it is false.

More details and examples of alternate axioms are in the Wikipedia article: https://en.wikipedia.org/wiki/Axiom_of_choice

If it seems weird that math can give you contradictory results, remember that the difference only shows up when you deal with some form of infinity (e.g. when performing an operation on an infinitely large set). For any usage of math in the real world, the truth or falsity of this axiom won't give you contradictory results.

lopsidedBrain | 5 years ago | on: Why and How zk-Snark Works (2019)

One of my highest-cited papers didn't pass peer-review. But that's okay. The citations (of the pre-print version) speak for themselves. If papers like these are good enough that new students entering the field use it as a ramp-up resource, they won't hesitate to cite it over and over again when they submit something for peer-review.

So journal publication is not the only means of recognition.

Speaking of which, computer science is a bit weird in that conference papers tend to have higher visibility than journals, even though the latter still has some of its grandfathered glory. Not all conferences are equal, obviously. Some have a more rigorous submission process than others. But our field definitely carries a bit of skepticism about the value added by journal publishers.

lopsidedBrain | 5 years ago | on: Dependency

Hmm. You're right, not if we are restricting ourselves to rectangles. But if we make A u-shaped, with B nestled in it, we'll be in business!

lopsidedBrain | 5 years ago | on: SQLite 3.33

If they have customers who need that kind of database, I'm sure they will be willing to help out with the testing. The setup doesn't have to be too crazy. Storage appliances with 20-30 hard drives are fairly common, actually. Even for individual humans, not just corporations. LVM allows you to easily create a logical volume out of multiple physical volumes, e.g. https://www.redhat.com/sysadmin/creating-logical-volumes.

You might find it interesting to look at the actual sqlite source commits where this change was introduced: https://sqlite.org/src/timeline?r=larger-databases It turns out the number comes from having a max of 2^32 pages in their database. Their default page being 4 kB each: https://www.sqlite.org/pgszchng2016.html

Working backwards, they must have raised it to 64kb: `python -c 'print(1024 * 64 * 232)'` produces 281,474,976,710,656.

lopsidedBrain | 5 years ago | on: SQLite 3.33

https://sqlite.org/limits.html

> SQLite was originally designed with a policy of avoiding arbitrary limits. [...] Unfortunately, the no-limits policy has been shown to create problems. Because the upper bounds were not well defined, they were not tested, and bugs were often found when pushing SQLite to extremes.

lopsidedBrain | 5 years ago | on: Google offers free fabbing for 130nm open-source chips

The material nature of hardware is barely any higher than that of software. Yes, you cannot just copy bits around, but you can take the same design and fabricate millions of chips for pennies. The cost of production for any given chip of Silicon has almost nothing to do with its material cost. It has everything to do with the amount of design work that went into it, just like software. None of that appreciably changes the benefits of cooperation vs competition.

lopsidedBrain | 5 years ago | on: The most successful developers share more than they take

I haven't looked at your past blogs, but it certainly sounds like you are making perfection the enemy of good. Your blogs don't have to be perfect, it just needs to be better than the current state, while not causing unanticipated regressions. Your blogs do not have to be prescriptive either. All you have to say is: I've tried x, y, and z, and it turned out better than a, b, and c in this-and-that manner. Provide your argument, and let readers judge whether your advice applies to their situation.

That said, if you do not have actual data or experience to back up what you are preaching, I definitely welcome the call for caution. It is not useful to insist that "everyone should learn a certain skillset" unless you found those skills relevant in practice in some situation.

It sounds like you've been compiling an interesting collection of stories, ones that might be interesting to a lot of folks here.

lopsidedBrain | 6 years ago | on: SELECT wat FROM sql

People generally expect equality to produce either true or false. Not a tri-value pair.

That interpretation makes sense to me when I read the docs, but is way too easy to miss when I'm actually doing comparisons.

lopsidedBrain | 6 years ago | on: Learning to See in the Dark (2018)

The comparison is fair because it tries to automate expertise.

I'm sure you know exactly how much of which filter to apply for similar results. Laymen like ourselves will need a lot more trial and error. Their contribution here is to provide a push-button, automated mechanism.

I would have probably also tried something simple and given up due to the noise. So this is definitely interesting.

lopsidedBrain | 6 years ago | on: Renaming files with mv without typing the name two times

My trick has always been to rely on tab auto-completion.

    mv foo-<tab>
    mv foo-bar-baz foo-<tab>
    mv foo-bar-baz foo-bar-baz
Now I can edit the second part pretty quickly.

Downside: you have to at least type `foo-` twice.

Upside: command line history still has the full command.

lopsidedBrain | 6 years ago | on: Exceptions should be Exceptional (2016)

That is sounds more appropriate for either terminating the program or resumable exceptions like division by zero. In languages with a try-catch construct (specially C++), the complexity of implementing exceptions has to do with stack unwinding. This is where you don't want to restart in an outer context, but want to guarantee cleanup for the call frames you are abandoning.
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