test trackback

http://kunwu.org/blog/2007/01/hello-world.html#links

## Friday, March 23, 2007

## Saturday, July 15, 2006

## Tuesday, April 18, 2006

### Fwd: Lunar2006 Calendar File in ICalendar Format

Now it can be accessed from http://kent.woo.googlepages.com/2006Lunar.ics

or http://icalx.com/public/kunwu/lunar2006.ics

or http://icalx.com/public/kunwu/lunar2006.ics

I found this file on this site http://liyingri.googlepages.com/2006Lunar.ics

Look into details of each day tips.

Look into details of each day tips.

## Wednesday, March 22, 2006

### CoDeen -- A CDN on PlanetLab

It's a wonderful project. Many nodes involved.

Here's the main link

http://codeen.cs.princeton.edu/

And the nodes list.

http://fall.cs.princeton.edu/codeen/

Here's the main link

http://codeen.cs.princeton.edu/

And the nodes list.

http://fall.cs.princeton.edu/codeen/

## Tuesday, March 21, 2006

### Verify the 72 Rule

Mimi told me a 72 rule last night. How many years does it need to double your balance while given a fixed interest rate? Using 72 divided by the interest rate. That it is.

The rule is verified by plotting the curves. Here's the m file for Matalb (v6.5). And some figures can be found below.

The rule is verified by plotting the curves. Here's the m file for Matalb (v6.5). And some figures can be found below.

% Years to double your balance

% WUKun, 21March,06

% function definition

fTheory = inline('log(2)/log(1+x)');

f72Rule = inline('.72/x');

% interest rate: 1% ~ 10%

interest = linspace(.01, .10, 100);

% years

for i = 1:length(interest)

yTheory(i) = fTheory(interest(i));

y72Rule(i) = f72Rule(interest(i));

end;

% plot

figure(1);

plot(interest, yTheory, 'k', interest, y72Rule, '-.r');

legend('Theory Curve', '72Rule Curve', 0);

grid on;

xlabel('Interest Rate');

ylabel('Years');

title('Years to double your balance');

%%%%%%%%%%%%%%%%%%%%%%%%

% -- What's about extend the scope of interest? --

interest = linspace(0.01, 10.0, 100);

% years

for i = 1:length(interest)

yTheory(i) = fTheory(interest(i));

y72Rule(i) = f72Rule(interest(i));

yError(i) = (yTheory(i)-y72Rule(i))/yTheory(i);

end;

% plot

figure(2);

subplot(1,2,1);

semilogy(interest, yTheory, 'k', interest, y72Rule, 'b', interest, yError, 'r');

legend('Theory Curve', '72Rule Curve', 'Error', 0);

grid on;

xlabel('Interest Rate (1%~1000%)');

ylabel('Years (log)');

title('Years to double your balance, Haha, the terrible interest!!!');

subplot(1,2,2);

plot(interest, yTheory, 'k', interest, y72Rule, 'b', interest, yError, 'r');

set(gca, 'xlim', [1 10]);

legend('Theory Curve', '72Rule Curve', 'Error', 0);

grid on;

xlabel('Interest Rate (100%~1000%)');

ylabel('Years');

title('Years to double your balance, Haha, the terrible interest!!!');

## Friday, January 20, 2006

## Sunday, December 25, 2005

### Host on sitesled now

I have a 100M space on sitesled, now.

This site can be accessed from China.

So I publish my weblog onto it.

Cool!

This site can be accessed from China.

So I publish my weblog onto it.

Cool!

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