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jdcarr

82 karma · joined October 24, 2014

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jdcarr··on Compressing Icelandic name declension patterns into a 3.27 kB trie
I use ConjuGato on iOS for practicing Spanish conjugations. There’s a game mode where you’re given an infinitive/tense/person and think of the conjugation and you can filter it down to solely irregular verbs to learn the exceptions
jdcarr··on UK: Food inflation rises to 18.2% as it hits highest rate in over 45 years
There are about 30 Costcos in the UK. You’re right that they aren’t particularly useful for weekly grocery shopping unless you have a car and a large fridge.
jdcarr··on Roe's overturn is tech's privacy apocalypse
I think there’s more preventing the passage of a law protecting an individuals right to abortion than whether it was a matter of political priority.

To pass such a law would require 60 votes in the senate AIUI. Given that this has been a massive part of the republican platform there’s no way ten senators would flip in the current senate.

It could have been passed in the Obama years but I wonder if the public would have had the appetite for it with the assumption that Roe vs Wade would have remained. Let sleeping dogs lie and all that

What this shows to me is the intentional inability for the senate to pass anything but the least offensive bipartisan bills and force other institutions such as the courts to intervene. However as we’ve seen the courts have their own agenda too

jdcarr··on Ask HN: What topics/subjects are worth learning for a new software engineer?
Ruby works out pretty nicely in that case!

  def order_list_by_predicate(l, &blk)
    l.partition{|i| blk.call(i)}.flatten
  end

  part(1..6) do |i|
    i % 2 == 1
  end
And you can always sort the incoming list if that's a requirement.
jdcarr··on In 1914, a 200ft wave at Trinidad, California (2014)
An amusing little sentence to end on:

> Event will be cancelled if hazardous weather conditions are predicted.

jdcarr··on Tesla issues strongest statement yet blaming driver for deadly crash
You're touching on one of the things that Tesla does that frustrates me to no end. They have this attitude of software being the solution to everything. Waymo has a reason they've mounted lidar to the roofs of their cars, it isn't because they can't build good enough software or their ML models aren't accurate enough, it's because they've realised that you can't just throw a bunch of cameras on a car, add some computer vision algorithms and market it to consumers as being fully self driving capable.
jdcarr··on Early Facebook and Google Employees Form a Center for Humane Technology
While the wording by the author is technically incorrect in that Google and Facebook aren’t operating a single supercomputer, the computing resources in possession of each company would almost certainly exceed any entry in the top500.
jdcarr··on More than 94% of net new electricity capacity in the USA from renewables in 2017
Do you have any thoughts on the benefits of decreasing the fragmentation of the US grid? Presently it's some 3000 utilities who don't have much of an incentive to work together, but you could imagine a future where regions of the US with excess generation transmit to areas at a deficit to diversify the energy supply of any region. This is roughly what's happening in China with their single public utility and usage of HVDC to source renewables from provinces with surplus generation to those operating at a deficit (i.e. the most populous).
jdcarr··on More than 94% of net new electricity capacity in the USA from renewables in 2017
With the staggering drop in the cost of renewables and grid-battery storage I just don't see how nuclear has a bright future in any regard.

They're unbelievably capital intensive and have a mean construction time of 7.5 years [0]. I'm from the UK so it's easy to point to Hinkley Point C as an example of this. It's been in planning for a decade and certainly won't be in operation for a similar amount of time, and the currently proposed strike price is around £90/MWh, compared to the ~£60/MWh we've seen from offshore wind projects. Let alone mentioning those have the advantage of being independently deployable with how developers can generate income on a per-turbine basis rather than waiting for the entire farm to be constructed.

And while nuclear is certainly much less CO2 intensive than any fossil-fuel source even a pro-nuclear body's publication shows that wind produces approximately as much CO2/GWh over an installations lifetime as nuclear does [1].

[0] http://euanmearns.com/how-long-does-it-take-to-build-a-nucle... [1] http://www.world-nuclear.org/uploadedFiles/org/WNA/Publicati... section 4

jdcarr··on How We Built Uber Engineering’s Highest Query per Second Service (2016)
The last time this was posted a few commenters mentioned using PostGIS instead of Uber rolling this themselves.

If anyone's used PostGIS with a similar level of traffic/latency requirements could you comment on your experience?

jdcarr··on Tesla Model 3 Hits Production
I can only speak for the brakes. Teslas use regenerative braking on the motor before falling back to traditional frictional brake pads as I understand it. Essentially the motor is put in reverse and that drains off speed. That means less wear on the brakes and so they last much, much longer than an ICE car.
jdcarr··on In 1957, Five Men Agreed to Stand Under an Exploding Nuclear Bomb (2012)
Radiolab had a great episode about nuclear weapons in the US.

At the ~51:26 mark of the episode http://www.wnyc.org/radio/#/747788 there's a great description of what the explosion of a hydrogen bomb was like.

jdcarr··on Electric Cars Soon Will Cost Less Than Gas Cars, Research Suggests
I've always enjoyed the alternate idea of parking areas having shelters covered in solar panels.

Has the nice advantages of keeping your car cool in the summer and removing another piece of complexity in your car.

You could also set up the charge stations such that they either draw from the solar panels or from an alternate power source in the winter when there isn't enough sun to keep a really simple solution.

jdcarr··on I Joined Airbnb at 52, Here’s What I Learned About Age, Wisdom, and Tech Industry
Individual Contributor
jdcarr··on Uber's head of communications is leaving the company
Do you have any evidence that the passenger was immature or belligerent beyond the United CEO initially claiming so?

And I don't see how you can wave away the incident just by claiming the actions were justified because of aviation law or how United runs.

jdcarr··on Introducing Cloud Spanner, a Global Database Service
> In terms of CAP, Spanner claims to be both consistent and highly available despite operating over a wide area, which many find surprising or even unlikely. The claim thus merits some discussion. Does this mean that Spanner is a CA system as defined by CAP? The short answer is “no” technically, but “yes” in effect and its users can and do assume CA. The purist answer is “no” because partitions can happen and in fact have happened at Google, and during some partitions, Spanner chooses C and forfeits A. It is technically a CP system.
jdcarr··on Introducing Cloud Spanner, a Global Database Service
Link to the actual OSDI paper (not the simpler whitepaper) https://static.googleusercontent.com/media/research.google.c...
jdcarr··on No One Saw Tesla’s Solar Roof Coming
Corrugated iron is infamously loud in rain. What type of metal roof are you considering that wouldn't be such an earsore?
jdcarr··on NSTouchBar API Reference
I think OP meant USB type A.
jdcarr··on Ask HN: How do you handle DDoS attacks?
The important thing you need to assess is how critical is it that clients receive fresh data.

You can imagine that for a real time service it would be better to provide a timeout immediately rather than providing stale data.

HN is an example of a near on-line site where some delay is perfectly acceptable. No one cares that they're receiving a 2 second old page, it's better for the site users to reveive old data fast rather than new data slow.

If you use nginx the following commands would help out significantly (if I remember them correctly)

proxy_cache_use_stale updating proxy_cache_lock on proxy_cache_lock_timeout 1s

This config allows nginx to fetch cache updates while serving clients and when fresh data is received from the upstream application server it'll use that immediately.

If that's wrong hopefully someone can correct the conf.

jdcarr··on Portugal runs for four days on renewable energy alone
Do you happen to know anything about offshore wind?
jdcarr··on One Billion Drive Hours and Counting: Q1 2016 Hard Drive Stats
Anecdotally, Google's file system Colossus uses Reed-Solomon 1.5x replication. So those 150 drives might only turn out to be in the low 200's.

And I remember reading a tweet from a Google engineer that they would be paged if their free storage dropped below 5PB.

jdcarr··on WebKit is now 100% ES6 complete
You might be missing the header row of the table listing various engines and their versions, and the little note that says "Performance of ES6 features relative to the ES5 baseline operations per second."

And I would assume that the baseline has been established on a per-engine basis.

jdcarr··on Saving Hundreds of Hours with Google Compute Engine Per-Minute Billing
We don't know their memory usage but if they use 1.5GB then they'll get 70 hours/month free from Amazon when using lambda [1], and it gets better from there depending on their usage.

But seeing as most of their work last less than an hour, I wonder how well they'd done to take advantage of the spot market.

Does anyone know of any tools that take advantage of the spot market? I know that Spark does [2].

[1] https://aws.amazon.com/lambda/pricing/ [2] http://spark.apache.org/docs/latest/ec2-scripts.html

jdcarr··on Microsoft Store doesn't accept Bitcoin anymore
But there's a clear difference between being able to make a chargeback within 45 days and a payment system without reversible transactions.

Authorising the card is instantaneous and the funds can be settled into your account within a couple of days.

jdcarr··on GitLab 8.5 released
It's a Spanish/English pun.

Todos means "all" in Spanish, so "all important things"

But also Todos as in multiple Todo items.

jdcarr··on Go 1.6 is Released
What's your use cases where you've found startup time to be a significant issue?
jdcarr··on Does Amazon Web Services Pricing Follow Moore's Law?
The point of his comment was that if Amazon have a fire that they'll deal with the issue, you won't have to do anything.
jdcarr··on Amazon.com redesign
Sorry to be pedantic, but it is possible to see your Amazon customerID.

Just view source on any Amazon page and search for customerID.

The A/B framework is pretty great and has a pretty amazing dashboard.