See also Learning

• Willpower
• Just One Thing
• The 7 Habits of Highly Effective People
• The Power of Habit
• The Now Habit

In their book Art & Fear: Observations On the Perils (and Rewards) of Artmaking, David Bayles and Ted Orland say that by their observation the elements that prove to allow a creative person to work are essentially idiosyncratic.

For example, they say, Hemingway discovered that in order to be productive, he needed to stand up while typing.

And, they continue, this discovery of Hemingway's is useless to nearly everyone else: other artists find what they need to be productive is something different.

Most productivity suggestions are naturally from people who found something that worked for them, and so recommend that's what you should do: "The Standing Up Method for Productive Writing".

So in lieu of a working general theory, the solution is to be experimental on a personal level: find a way to measure your productivity, even if subjectively, vary your working conditions in systematic way, and see what makes a difference for you.

– www.greaterwrong.com/posts/NyFtHycJvkyNjXNsP/chaotic-inversion?commentId=oGXDkvKc2XDJKJEQ6

A typical city grows in two dimensions, and would happily grow in three and four and five if it was possible.

That doesn't mean it should.

A basic problem of city planning is making sure everything is within reasonable reach of every highway, bus route and subway station, while not spending too much.

What's a city planner's wet dream? That this would be straightforward, easy. That you could predict the load on a given section of subway, now and in the future.

Suppose you didn't have any cities. You're a king in a country of farmers. What even is a city, they ask you.

Suppose you then build a stretch of rail across your kingdom. With no particular location to connect to, you can choose the flattest parts of land, to make your rail as cheap and straight as possible. It's still expensive, but it lets farmers from one end trade with farmers from the other end.

You build your castle and other stuff along this rail. Eventually there are marketplaces, industries, services, hotels, and apartment buildings. The rail is starting to pay for itself. Ford is marketing a new thing called 'automobile', but you feel no need to import any. There's still plenty of empty spots along your rail, and all buildings are within walking distance of the rail. Even bicycles don't interest anyone: the train is fastest.

Commute is sometimes long. But there is now so much dense cityscape along your rail, that you can afford to build a vacuum-tube train. Now commute is short, always short. The use of the vactrain is 100%: it's perfectly placed, so its potential is reached.

#statistics, Identifying power law data

Under at least one definition, a fat-tail distribution is one whose tail is fatter than that of the exponential distribution.

Examples

• Cauchy
• Pareto
• Zipf
• Weibull with low k parameter

All exist in Stan.

Pareto and Zipf are both simple power laws with a negative exponent, scaled so that their cumulative distributions equal 1. The difference is that Zipf is discrete.

The "80-20 law", according to which 20% of all people receive 80% of all income, and 20% of the most affluent 20% receive 80% of that 80%, and so on, holds precisely when the Pareto index is α = log₄(5) = log(5)/log(4), approximately 1.161.

80-20 also implies 64/4 and approx. 50/1 (51.2/0.8)

Cauchy has no well-defined mean.

#emacs

The command find-dired lets you generate a dired buffer out of Find results.

wdired lets you edit file names and attributes with normal buffer editing commands. You know how C-x C-q is the standard "toggle read-only" binding? Well, C-x C-q toggles wdired.

What's often not mentioned about WDired is:

• As well as renaming a file you can move it, e.g. Change the name to ../../name and it moves up two parent folders as well as changing name.
• if the file is a symlink you can just change its target too
• file attributes, sure just change them in WDired too. (Needs wdired-allow-to-change-permissions set to t)
• change the name to blank, the file will be deleted

You can use any character to mark files and then perform an operation on a specific type of mark. That's why deleting uses its own mark character. So go through lots of files marking some a and others b and yet others c and then move them all to different places.

In fact any shell command can be run on selected files using the ! command.

For subdirs, i calls dired-maybe-insert-subdir, and an alternative is dired-subtree from Fuco1's dired-hacks. But I suspect it's better to adopt a buffer-proliferate approach than to try to keep everything in one Dired buffer. One use i can see is mass renaming recursively with wdired, where you first have to insert all the subdirectories. To do that, C-u C-8 C-x C-j (any numeric arg) and add the -R switch.

Marking files: you can mark a region and then press m to mark all files within.

The m key is really a shorthand for * m, but there are other marking commands like as follows. Note that these can be a transient map / hydra.

• * m mark this file
• * * mark all executables
• * @ mark all symlinks
• * s mark everything
• * ! (shorthand: U) unmark all files
• * C-n (or M-}) move to next marked file
• * t toggle marks (colloquially, "invert selection")
• * % REGEXP mark files whose names match REGEXP
  • % m REGEXP (synonym to above)
  • % g REGEXP mark files whose contents contain a match for REGEXP