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bladecatcher

816 karma · joined December 3, 2009

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bladecatcher··on K Language (2011)
Great point re: the “Bespoke” style of programming. It takes some unlearning and getting used to tacit programming [0] and trains [1] to appreciate this.

I’ve worked on fairly complex systems using kdb/q that are a joy to debug because the codebase is a handful of files. q is admittedly a more simplified and “mainstream” cousin of J, but allows a fair bit of expressiveness. The powerful data store (kdb) and q-sql that comes along with it makes it one of the most concise data platforms ever. Too bad it’s not free for commercial use!

[0] https://www.jsoftware.com/help/jforc/tacit_programs.htm

[1] https://www.jsoftware.com/help/learning/09.htm

bladecatcher··on ksqlDB: Event streaming database for stream processing applications
> Now if it were possible for it to accept an event from Kafka but not guarantee that the event will eventually make it into the materialized view but may be lost, that'd be a problem.

This is usually not a problem these days as it’s possible to guarantee exactly once ingestion using Kafka offsets

bladecatcher··on ksqlDB: Event streaming database for stream processing applications
You’re right. You don’t get read-your-own-writes guarantees in a typical Kdb tickerplant architecture, as the event streams are propagated to the real-time nodes asynchronously.
bladecatcher··on ksqlDB: Event streaming database for stream processing applications
I think the usecase for this is streaming queries and aggregations where the query output is materialised asynchronously
bladecatcher··on Marchetti's constant
In Indian cities like Mumbai, Bangalore, one can easily spend 3 to 4 hours a day commuting
bladecatcher··on Resiliency with Queues: Building a System That Never Skips a Beat in a Billion
I suppose one can measure the risk of losing messages - I’m not suggesting that it’s always possible, but calling it an unmeasurable risk is probably not true
bladecatcher··on In Praise of APL: A Language for Lyrical Programming (1977)
Typically, one would start off in a quant trading desk which uses kdb+ for their analytics or join First Derivatives [0] that trains graduates

[0] https://www.firstderivatives.com/

bladecatcher··on In Praise of APL: A Language for Lyrical Programming (1977)
https://code.kx.com/q/ has learning material and documentation . Hope it helps
bladecatcher··on In Praise of APL: A Language for Lyrical Programming (1977)
You can start the 32 bit instance with the -s switch (for q to be started with multiple slaves) for parallel execution of a function over data using the "peach" command [0].

But yes, I do agree that the 32 bit instances have limited use, as they can't be used in for-profit projects.

[0] https://code.kx.com/wiki/Reference/peach

bladecatcher··on In Praise of APL: A Language for Lyrical Programming (1977)
As mruts pointed out above, kdb+/q provides what you're imagining - it provides fantastic distributed computing support via its IPC protocol and also has multi-core support.
bladecatcher··on In Praise of APL: A Language for Lyrical Programming (1977)
Related article posted on HN recently:

APL is more French than English [https://news.ycombinator.com/item?id=18640451]

bladecatcher··on Pre-sleep treatment with galantamine stimulates lucid dreaming
Those who’re interested in lucid dreams should definitely watch the film Waking Life - https://en.m.wikipedia.org/wiki/Waking_Life
bladecatcher··on 'Unique' cannabis compound reverses brain aging in mice
>> Which substances are you talking about because I'm talking about Cannabis

I see. That might be true in most cases, but even Cannabis can have adverse effects on people with predisposition to mental illnesses

bladecatcher··on 'Unique' cannabis compound reverses brain aging in mice
That's very dangerous advice. These substances can warp you mind in irrecoverable ways. Plenty of people also end up in asylums and ER
bladecatcher··on Mumbai bans plastic bags, bottles, and single-use plastic containers
That's true, but bioplastics degrade on timelines that are magnitudes smaller than actual plastic.
bladecatcher··on Mumbai bans plastic bags, bottles, and single-use plastic containers
http://www.algopack.com/indexgb.php makes bottles out of seaweed (brown algae) and there're other companies trying to make reuseable bioplastic bottles out of sugarcane
bladecatcher··on China is no longer importing waste – 111M tons will have to go elsewhere
Although not yet commercially viable there are a few companies trying to address this problem. Algopack[0], a French startup is making plastic like material from seaweed (brown algae) and there are others that are trying out bioplastics made from sugarcane

[0] http://www.algopack.com/algopackgb.php

bladecatcher··on Eigenvectors and Eigenvalues (2015)
It’s possible to understand eigen-* without having an understanding of determinants. That’s how they’re introduced in “Linear Algebra Done Right” - http://linear.axler.net/
bladecatcher··on BlackRock Backs a Startup to Find Out What Young Investors Want
A product like this makes sense for Blackrock because they also are in the privileged position of creating the ETFs in the portfolio.
bladecatcher··on Trinitron: Sony's Once Unbeatable Product [video]
Did you mean causation and not correlation here?
bladecatcher··on Consciousness Goes Deeper Than We Think
Not sure where your 22 years estimate comes from. I think man has been trying to understand it for much longer maybe thousands of years ? - and has found answers through techniques that are outside of the mind - such as meditation.
bladecatcher··on Consciousness Goes Deeper Than We Think
>> Instead, we should switch to the low level dual of this problem - game theory and reinforcement learning

This sounds a bit naive.

bladecatcher··on Database Learning: Toward a Database That Becomes Smarter Every Time
Their paper "Self-organizing tuple reconstruction in column-stores" [0] provides more details on this.

[0] https://pdfs.semanticscholar.org/1d5c/bc071f918143dbedf67a51...

bladecatcher··on Database Learning: Toward a Database That Becomes Smarter Every Time
MonetDB[0] is an open source OLAP engine which does cracking.

From the Wikipedia page:

"Cracking is a technique that shifts the cost of index maintenance from updates to query processing. The query pipeline optimizers are used to massage the query plans to crack and to propagate this information. The technique allows for improved access times and self-organized behavior."

[0] https://www.monetdb.org/content/column-store-features

bladecatcher··on Random – Probability, mathematical statistics, and stochastic processes (2015)
this is one of the most comprehensive treatments of the subject I've found. Also works great as a reference/hand book
bladecatcher··on International Travel Guide for Basecamp employees
It's not clear to me whether the US Border control can ask you to login on their desktop even if you're not carrying any devices. In such a case, there's no way to avoid being subject to search.
bladecatcher··on New Features Coming in PostgreSQL 10
Isn't analytics a massive usecase in itself?
bladecatcher··on New Features Coming in PostgreSQL 10
This is great because I couldn't go to production with earlier releases of logical decoding. Now we don't have to depend on a third party add on!
bladecatcher··on Cantor diagonalisation
A most merry and illustrated explanation of the diagonal argument: http://www.coopertoons.com/education/diagonal/diagonalargume...
bladecatcher··on Seeing Theory: A visual introduction to probability and statistics
Link to recent discussion : https://news.ycombinator.com/item?id=13735714
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