Skip to main content

Bus Surfing, Dorian Gray, and Loveness


The gang, (7 y.o. No. 1, 5 y.o. No. 2 and 3 y.o. No. 3), are reading "The Picture of Dorian Gray" this week.  I hear that the story will become more variated as we go on, but for the moment, it's been easy-going and pleasant.  Two somewhat attractive men, one an artist putting the finishing touches on what may be his greatest painting, the other a Lord lounging on a divan made Persian saddle bags are discussing a beautiful man, the subject of said artist's, said painting.  This, like The Island of Dr. Moreau before it has sprung from 2's interest in ghosts and zombies, and our library's book group studying Mystery and Horror in Victorian England.  So far, it's a blast.  We're learning new words, new turns of phrase, and new, albeit fictional and archaic, surroundings.

The gang have also been studying movement.  They're working on balance, strength, and falling.  Their work has changed our public transit system from a living room surrogate to a gym.  No. 1 can grab  of bars on either side of the bus at once, and is practicing her hang-time, (literally), suspending herself in midair for ever increasing intervals as we travel around town.  No. 3 can't reach both bars, and so has contented herself instead with a form of bus and train surfing to work on balance.  Positioning herself on the conveyance as if it were a long surfboard, she puts her arms out, bends her knees, and practices taking the dips and curves.

The gang is still soldering, still learning reading, and still exploring.  In the past week, 3 ramped up her art production, highlighted by presenting us with a squiggly, abstract sketch of... 'Loveness'.

Comments

Popular posts from this blog

Cool Math Tricks: Deriving the Divergence, (Del or Nabla) into New (Cylindrical) Coordinate Systems

Now available as a Kindle ebook for 99 cents! Get a spiffy ebook, and fund more physics
The following is a pretty lengthy procedure, but converting the divergence, (nabla, del) operator between coordinate systems comes up pretty often. While there are tables for converting between common coordinate systems, there seem to be fewer explanations of the procedure for deriving the conversion, so here goes!

What do we actually want?

To convert the Cartesian nabla



to the nabla for another coordinate system, say… cylindrical coordinates.



What we’ll need:

1. The Cartesian Nabla:



2. A set of equations relating the Cartesian coordinates to cylindrical coordinates:



3. A set of equations relating the Cartesian basis vectors to the basis vectors of the new coordinate system:



How to do it:

Use the chain rule for differentiation to convert the derivatives with respect to the Cartesian variables to derivatives with respect to the cylindrical variables.

The chain rule can be used to convert a differe…

Division: Distributing the Work

Our unschooling math comes in bits and pieces.  The oldest kid here, seven year-old No. 1 loves math problems, so math moves along pretty fast for her.  Here’s how she arrived at the distributive property recently.  Tldr; it came about only because she needed it.
“Give me a math problem!” No. 1 asked Mom-person.

“OK, what’s 18 divided by 2?  But, you’re going to have to do it as you walk.  You and Dad need to head out.”

And so, No. 1 and I found ourselves headed out on our mini-adventure with a new math problem to discuss.

One looked at the ceiling of the library lost in thought as we walked.  She glanced down at her fingers for a moment.  “Is it six?”

“I don’t know, let’s see,” I hedged.  “What’s two times six?  Is it eighteen?”

One looked at me hopefully heading back into her mental math.

I needed to visit the restroom before we left, so I hurried her calculation along.  “What’s two times five?”

I got a grin, and another look indicating she was thinking about that one.

I flashed eac…

The Javascript Google URL Shortener Client API

I was working with the Google API Javascript Client this week to shorten the URLs of Google static maps generated by my ham radio QSL mapper. The client interface provided by Google is very useful. It took me a while to work through some of the less clear documentation, so I thought I'd add a few notes that would have helped me here. First, you only need to authenticate your application to the url shortener application if you want to track statistics on your shortened urls. If you just want the shortened URL, you don't need to worry about this. The worst part for me was that the smaple code only showed how to get a long url from an already shortened rul. If you follow the doucmentaiotn on the insert method, (the method for getting a shortened url from a long one), there is a reference to a rather nebulous Url resource required argument. It's not at all clear how to create one of these in Javascript. The following example code shows how:
var request = gapi.clie…