find, xargs

Originally shared by Xah Lee

: the most powerful shell command. Master it. find, xargs. Here’s some commen patterns:

#  show just files ending with .html

find . -name “*.html”

# larger than 9 Mega bytes

find . -size +900000c

# delete all files whose name ends with ~.

find . -name “*~” -exec rm {} \;

# delete all empty files

find . -type f -empty -exec rm {} \;

# delete empty dirs

find . -depth -empty -type d -exec rmdir {} \;

# file status changed in last 60 min

find . -cmin -60

# file content modified in last 60 min

find . -mmin -60

for more, using xargs examples, see

http://xahlee.info/linux/linux_shell_find_example.html

 

Laniakea: Our Home Supercluster of Galaxies

Originally shared by Astronomy Picture of the Day (APoD)

Laniakea: Our Home Supercluster of Galaxies

Image Credit: R. Brent Tully (U. Hawaii) et al., SDvision, DP, CEA/Saclay

http://apod.nasa.gov/apod/ap140910.html

It is not only one of the largest structures known — it is our home. The just-identified Laniakea Supercluster of galaxies contains thousands of galaxies that includes our Milky Way Galaxy, the Local Group of galaxies, and the entire nearby Virgo Cluster of Galaxies. The colossal supercluster is shown in the above computer-generated visualization, where green areas are rich with white-dot galaxies and white lines indicate motion towards the supercluster center. An outline of Laniakea is given in orange, while the blue dot shows our location. Outside the orange line, galaxies flow into other galatic concentrations. The Laniakea Supercluster spans about 500 million light years and contains about 100,000 times the mass of our Milky Way Galaxy. The discoverers of Laniakea gave it a name that means “immense heaven” in Hawaiian.

 

Note to the reader: Some people have been upset that I’m writing more about issues like these lately, and don’t want…

Originally shared by Yonatan Zunger

Note to the reader: Some people have been upset that I’m writing more about issues like these lately, and don’t want to hear about things like race in America. If you feel this way, you may continue to be disappointed: these things are important, and we need to talk about them. Consider yourself forewarned: there will be more of this. If this makes you unhappy, you may want to stop reading now. But you probably shouldn’t: if you find that this brings up lots of complicated emotions for you, that’s a sign that you should read more, not less.

I wish that I could give you a short version of this article. But you need to read this, because it’s going to be important to our national conversation about many things. Radley Balko has written a deeply researched, detailed article about the system of institutionalized corruption by which municipalities across Missouri are essentially treating their poor — especially their black poor — as a resource to be harvested and consumed to line their own pockets.

The basic idea is simple and should be familiar to anyone who’s watched loansharks at work: they start with a fine for something — say, having expired tags on your car, not having proof of insurance, or (I kid you not) “wearing saggy pants.” If you don’t have a lawyer (and they’ve made sure that you won’t have one unless you’re rich enough to hire one), then you don’t simply pay the fine; instead, you have a series of court dates. The message seems to somehow have gone out to the public that if you go to one of these dates and can’t afford the fine, you’ll go to jail — so people miss the dates, and are then arrested for that, instead. Then they get fined for that, as well. As well as fines for not paying the fines, and so on, and so forth. 

It’s brutally effective, and it’s why you hear so much concern about towns which are 90% black with a police force that’s almost entirely white and living in a different town: that police force is, generally, running one of these schemes, together with a local government that’s arranging all of the payments. (Guess where all the money for this goes? Hint: it’s not the town general fund. At least, not the town where any of the people being imprisoned live.) When the people writing and “enforcing” (I use the term loosely) the laws have no ties to the people being charged under them, you have a sophisticated extortion racket, and no rule of law.

This article is extensive and detailed, and by the time you get through it, you should have a painfully clear picture of how it works. There are probably two other things you should read in conjunction with it: Ta-Nehisi Coates’ now-famous article about similar corruption of the housing system (http://www.theatlantic.com/features/archive/2014/05/the-case-for-reparations/361631/), and the book I’m working through now, Douglas A. Blackmon’s Pulitzer Prize-winning Slavery by Another Name. (http://www.amazon.com/Slavery-Another-Name-Re-Enslavement-Americans/dp/0385722702) I suspect that these three will give you a very good picture of some of the “hidden corruption,” of the darkest form imaginable, which plagues our country to this day.

http://www.washingtonpost.com/news/the-watch/wp/2014/09/03/how-st-louis-county-missouri-profits-from-poverty

 

The lectures of Nobel Prize winning physicist Richard Feynman were legendary.

Originally shared by David Fuchs

The lectures of Nobel Prize winning physicist Richard Feynman were legendary. Footage of these lectures does exist, but they are most famously preserved in The Feynman Lectures. The three-volume set may be the most popular collection of physics books ever written, and now you can access it online, in its entirety, for free.

http://io9.com/you-can-now-access-all-of-richard-feynmans-physics-lect-1627809095