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cgrubb

237 karma · joined July 5, 2010

Los Angeles
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cgrubb··on Netflix lost 9% of the market share as competition increases
Logged in to say this. Market share is a confusing stat when customers don't exclusively use one service.

Netflix is still adding subscriptions at a good rate.

https://www.businessofapps.com/data/netflix-statistics/

cgrubb··on A Quick and Easy Guide to Tmux (2015)
tmux attach
cgrubb··on Chinook Wawa, a pidgin language that combined Nootka, Chinook, French, English
> It was used so extensively that it was the language of courts and newspapers in the Pacific Northwest from about 1800 to 1905. This makes it sound like all the newspapers were in Chinook Jargon. But the only such paper I've been able to find was this https://en.wikipedia.org/wiki/Kamloops_Wawa —first published in 1891 and doesn't seem to have had too wide of a circulation.
cgrubb··on Wages for college graduates across many majors have fallen since the recession
Saturation or oversupply seem possible. Number of bachelors degrees awarded in 2015 was 14% higher than in 2010, but US population increased only 3% during this time.

https://nces.ed.gov/programs/digest/d16/tables/dt16_322.10.a...

http://www.multpl.com/united-states-population/table

cgrubb··on Ask HN: Which non-technology book has influenced you the most and why?
The Rock Warrior's Way:

https://www.amazon.com/Rock-Warriors-Way-Training-Climbers/d...

Nominally about rock climbing, but really a study of the ego, why we invest so much effort in protecting it, and how little we get for that investment.

cgrubb··on The end of smartphone innovation
The Thomas Watson quote (only a market for 5 computers) is a bit of an urban legend:

http://geekhistory.com/content/urban-legend-i-think-there-wo...

cgrubb··on GNU APL 1.7 Released
I think this is a good youtube video for someone starting from zero:

https://www.youtube.com/watch?v=_DTpQ4Kk2wA

An issue is how to enter the symbols. The way I do it is I created some input methods for Mac and Windows which use at-signs followed by the APL community name for the symbol:

    @times       ×
    @grade       ⍋ 
    @reverse     ⌽
    @domino      ⌹
https://github.com/clarkgrubb/latex-input/tree/master/apl
cgrubb··on What happened to Python?
I upgraded from 2 to 3 last year. I'm liking it.

I've embraced type hints. Although they have no run-time effect, there is a command line tool called mypy which enforces correctness. It has caught more than a few errors for me. Declaring the types of arguments and return values is a help when reading the code imo.

cgrubb··on Los Angeles Drivers on the 405 Ask: Was $1.6B Worth It?
A light rail system over Sepulveda Pass would probably require drilling a tunnel. Early estimates are at least $6B: http://www.latimes.com/local/lanow/la-me-ln-sepulveda-pass-t.... It could get built, but I don't think the final price tag is going to put the lane expansion to shame.

Buses can already use the HOV lanes. One of the expansion lanes (the northbound one) was an HOV lane, so now there are HOV lanes in both directions. Who cares, given how few riders buses attract.

cgrubb··on Los Angeles Drivers on the 405 Ask: Was $1.6B Worth It?
There is precedent for charging $2 tolls in CA: https://en.wikipedia.org/wiki/California_State_Route_73
cgrubb··on Los Angeles Drivers on the 405 Ask: Was $1.6B Worth It?

    Vehicle capacity on the northbound 405 has increased from 10,000
    vehicles per hour to 11,700 vehicles per hour at peak times. 
http://thesource.metro.net/2015/05/28/study-finds-traffic-on...

So capacity increased maybe 10k a day, or 750M over a 20 year period. Makes the $1B investment seem reasonable.

cgrubb··on Jay Z: ‘The War on Drugs Is an Epic Fail’ [video]
Releasing all drug offenders (both federal and state) would reduce the US prison population 14%: http://fivethirtyeight.com/datalab/releasing-drug-offenders-...
cgrubb··on Apollo astronauts dying of heart disease at 4-5X the rate of counterparts
> Is that even statistically significant?

Not if your significance level is the customary 5%:

    > 1 - pbinom(2, 7, 1/7)
    [1] 0.06522914
The astronauts carried dosimeters, and all got rad doses below what some DOE employees get, so maybe there is better population for an observational study.
cgrubb··on Ask HN: What programming language has you really excited lately, and why?
jq is a command line tool and also a language for expressing transformations on JSON with concise one-liners. It is useful for processing the output of mongoexport or an elasticsearch query.

The basic constructs are "filter expressions". Pipes (|) can be used to direct the output of one filter expression to another, and commas (,) can be used to concatenate the output of two filter expressions.

cgrubb··on Coursera shuts access to old platform courses
My downloads:

    - ac-005: Analytic Combinatorics
    - aofa-006: Analysis of Algorithms
    - neuralnets-2012-001: Neural Networks for Machine Learning
    - nlp: Natural Language Processing
cgrubb··on Developers don't build cheaper housing because we make it illegal (2014)
Yep. In LA Large empty lots are hard to come by. A 6k square ft lot might be 100k for an undesirable location in an undesirable nbhd, but 400k is probably typical. Not sure how much cost "zoning and permitting" really adds on top of that.
cgrubb··on Venezuela is on the brink of a complete economic collapse
The Venezuela wikipedia page makes it sounds as if the Bolivarian Revolution is a repeat of history:

    The election of Carlos Andrés Pérez in 1973 coincided
    with the 1973 oil crisis, in which Venezuela's income
    exploded as oil prices soared; oil industries were 
    nationalized in 1976. This led to massive increases in 
    public spending, but also increases in external debts, 
    which continued into the 1980s when the collapse of oil 
    prices during the 1980s crippled the Venezuelan economy.
    As the government started to devalue the currency in 
    February 1983 to face its financial obligations,
    Venezuelans' real standards of living fell dramatically.
    A number of failed economic policies and increasing 
    corruption in government led to rising poverty and crime,
    worsening social indicators, and increased political 
    instability.
cgrubb··on People Are Still Trying to Build a Space Elevator
Space elevator shadow wouldn't look like that: https://en.wikipedia.org/wiki/Umbra,_penumbra_and_antumbra
cgrubb··on Why Python 3 Exists
> You always "encode" something into bytes, and "decode" bytes back into something. There should be exactly two functions, because the functions have different types: "encode" is str -> bytes, "decode" is bytes -> str. Explicit is better than implicit.

I'm not sure "encoding" tells us that the output is bytes. Surely information can be encoded in other ways. Names like .to_bytes() and .from_bytes() might have saved a lot of trips to the documentation.

cgrubb··on Claimed proof of Riemann Hypothesis
The paper uses results from "Grandes valeurs de la fonction somme des diviseurs et hypothèse de Riemann" by Robin, which is not available online, as far as I can tell.
cgrubb··on 13,000 fall into homelessness every month in L.A. County
That number is the result of the massive, largely volunteer effort led by HUD to count the homeless that is done every January. There are other numbers, but they tend to involve a lot more guesstimating and a lot less data.
cgrubb··on 13,000 fall into homelessness every month in L.A. County
Some more numbers:

    US         578,424   318.9M      0.18%
    LA County   44,359    10.02M     0.44%
    LA City     25,686     3.88M     0.66%
https://www.hudexchange.info/resources/documents/2014-AHAR-P... http://www.lahsa.org/homelesscount_results
cgrubb··on American Trailer Parks: The owners are getting rich
I'm thinking the energy to boil the amount of water which falls naturally on California is about 500 times what the electrical grid currently delivers (300,000 Gwh). Estimating avg rain fall over the state at 15 in = 38.1 cm, so 1.62 x 10^14 liters.

    http://ponce.sdsu.edu/california_average_annual_precipitation.html
    http://energyalmanac.ca.gov/electricity/total_system_power.html
cgrubb··on Mass Incarceration: The Silence of the Judges
You source appears to be for federal prisons only. Those numbers only add up to about 200k inmates. Most people are imprisoned by the state or county.
cgrubb··on Mass Incarceration: The Silence of the Judges
prison population by type of crime (2012):

    violent: 47.7%
    property: 17.1%
    drug: 20.5%
    public order: 13.8%
"public order" includes drunk driving, weapons possession, and prostitution. Source http://felonvoting.procon.org/view.resource.php?resourceID=0...

Recidivism rates (2005):

    violent: 71.3%
    property: 82.1%
    drug: 76.9%
    public order: 73.5%
Source: http://www.nij.gov/topics/corrections/recidivism/Pages/welco...
cgrubb··on Hyperpolyglot
Thanks for the note. I didn't interpret it as an attempt to take credit. No offense taken.
cgrubb··on How Houston Gets Along Without Zoning Laws
I like Houston but I have only visited. If I were to live there, I would live inside the 610 loop, which has reasonable density. It is still a driving city, though.

The closest thing to a walking city are the underground tunnels downtown. However, as another commented, the downtown empties out at night; at least that was the case 20 years ago. Houston is very hot in the summer, so a walking city is probably not a reasonable thing to ask for.

One of the absurdities was the Transco tower, called today the Williams tower. It used to be the tallest building in Houston, and it is outside the 610 loop and 4 miles from the downtown. Everything around it is quite small and it is difficult to understand what economics motivated building it.

Update: I'm trying to think why I like the city. I guess it is the vegetation. Houston is perhaps a bit like how Mayan cities must have been.

cgrubb··on Danish study: moderate jogging, higher benefits
7mph is a speed a lot of people can't run. Those are 8 1/2 minute miles. It corresponds to a speed of 26min for a 5k.

This article

  http://www.letsrun.com/forum/flat_read.php?thread=4612823
has some stats for a 5k race. The average time for men was 28min, and only 10% of the women were faster than 26min.

Slower speeds might skew towards women, who naturally live longer.

Another thought is that people who run fast do so over shorter distances, and their volume isn't sufficient to see a health bump.

cgrubb··on Behind OS X’s modern face lies an aging collection of Unix tools
also make, which is stuck at 3.81 (2006)

sort appears to be (2005), and doesn't have the -R flag for shuffling

also missing: head -n -NUM (all but last NUM lines) and tail -n +NUM (all but the first NUM lines)

cgrubb··on A computer algebra system written in Python
The Sympy guys have a good comparison:

https://github.com/sympy/sympy/wiki/SymPy-vs.-Sage

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