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Here's another article; this one contains a video by the paper author

https://theconversation.com/a-mysterious-interstellar-radio-...


Thanks! It's much nicer to see the videos.

Stellar taxonomy and ecology is so interesting.

And while pulsar is a cool name, I think we missed our chance to name them whobblars.


Fascinating, thanks for sharing! According to that article a second source has been discovered since the linked paper was published.


From the link:

12.1 The following terms apply only to current and future Google Cloud Platform Machine Learning Services specifically listed in the "Google Cloud Platform Machine Learning Services Group" category on the Google Cloud Platform Services Summary page

Those services are (from https://cloud.google.com/terms/services):

  - Cloud AutoML
  - Cloud Text-to-Speech
  - Dialogflow Enterprise Edition
  - Google Cloud Data Labeling
  - Google Cloud Natural Language
  - Google Cloud Speech-to-Text
  - Google Cloud Video Intelligence
  - Google Cloud Vision


Right - that is the Google Cloud Machine Learning Group, which are managed ML-as-a-service products.

If you read the list, you will see they're highly specialized, out of the box ML products and super easy to resell, hence the TOS restrictions.


An engine compressor stall (which is more common at low altitude and high thrust) can cause fire to come from the engine.

https://www.youtube.com/watch?v=MQWYhsYfMxE (jump to 1 minute for an example, found in an earlier HN thread).


For me the hidden video starts (hidden) when I open the page, so when I click 'Watch the video' it's already part way through.

Firefox 65.0 on MacOS 10.14.


This is spec: https://clojure.org/about/spec

All spec errors turn up at run time. See the guide for more details: https://clojure.org/guides/spec.

You can combine spec with test.check (Clojure's quick check library) https://clojure.org/guides/spec#_generators


Click the date/time on a tweet to get the permalink.

Here's the tweet you referenced: https://twitter.com/_delta_zero/status/1054820799473836032


Ahh, that was the one place I did not look, thank you!


From the license https://www.datomic.com/datomic-pro-edition-eula.html

> The Licensee hereby agrees ... it will not: ... (j) publicly display or communicate the results of internal performance testing or other benchmarking or performance evaluation of the Software;


This kind of clause is usually known as a "DeWitt clause"[1], after a University of Wisconsin professor who benchmarked a couple databases, including Oracle (which performed poorly). Oracle/Larry Ellison didn't react well to that and decided to forbid benchmarks.

[1]: https://danluu.com/anon-benchmark/


Database performance depends on so many variables - thread pools, queue sizes, RAM allocations to different purposes, disk layout - the list goes on. There are whole consulting fields that are essentially doing a random walk through database configuration files looking for better performance - ascending the performance gradient if you will.

So in this world, its sensible to say "benchmarks are uninformative and misleading - your mileage will almost certainly vary"


Benchmarks are easily abused, misused, and misinterpreted. E.g., benchmarks looking at some very specific aspect of query performance being extrapolated to more complex/real-world queries.

Also trade-offs are rarely mentioned in benchmark numbers– e.g., great write throughput, at the expense of: ?.

It's fun to be cynical about stuff like this, but it's rarely as simple as "Ellison didn't react well to that and decided to forbid benchmarks".


> Oracle/Larry Ellison didn't react well to that and decided to forbid benchmarks.

So you kind of have to wonder why Cognitect is going Oracle on us..

The most obvious explanation is that Datomic just doesn't perform well and they don't want people to know.


Anyone who has done serious performance testing on a DB knows that there's a massive gap between initial findings and a well tuned system designed with the help of the database maintainers. I've seen some nasty performance out of Riak, Cassandra, SQL, ElasticSearch etc. But with each of those, once I talked to the DB owners and fully understood the limitations of the system it was possible to make massive gains in performance.

Databases are complex programs, and if I ever wrote one, it would be infuriating for someone to pick it up, assume it was "just like MySQL" and then write a blog post crapping on it because it failed to meet their expectations.


Yes, benchmarks can give a misleading impression of a database's performance.

So what? Somehow PostgreSQL is doing fine despite that.

Which is worse publicity for Cognitect: people publishing bad benchmarks or Cognitect forbidding benchmarks Oracle style?


Well, the absurd one was:

>the license at least used to forbid even saying "Datomic" aloud in public.


The code associated with the book is all on Github: http://github.com/crista/exercises-in-programming-style


I think you're being a little bit unfair. The same block then continues:

  This is called an integer overflow. At best, we might just get an error. At worst, our computer might compute the correct answer but then just throw out the 9th bit, giving us zero (0000 0000) instead of 257 (1 0000 0000)! (Python actually notices that the result won't fit and automatically allocates more bits to store the larger number.)
The article is introducing the concept of integer overflow.


1111 1111 = 255

1 0000 0000 = 256

Anyone who claims to understand integer overflow from actual experience, rather than memorizing textbooks, should know that by inspection.

I'd forgive that in a CS grad (possibly) but if someone claimed to have been working in C or other unsafe languages for more than a trivial amount of time I'd be very suspicious.


That's only assuming 0-based numbers :)


(I know you're being tongue-in-cheek, but)

> our computer might compute the correct answer but then just throw out the 9th bit, giving us zero (0000 0000) instead of 257 (1 0000 0000)!


Well he did say he didn't read any further.


I like Zoom (http://zoom.us/). I used to use Hangouts, but it consumed a lot of CPU. The free Zoom account allows you to have up to fifty people in a room for forty minutes, or an unlimited length call with just two participants.


I've used zoom.us quite a bit and was family impressed. There's also appear.in which is not as good, but doesn't have all the restrictions the free zoom.us tier has.


I just encountered Zoom this week! I had a conference with a German (I'm in Vietnam at the moment) and she sent me a link to it. I'd never heard of it and was a bit frustrated to need to install another plugin.

But it was a great experience compared to Hangouts! The connection quality was on par with Skype and it was super light-weight for something based in the browser.

8.5/10, would use again.


What's it like on poor connections? What's the quality like?


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