Two Letters in One Day

March 1st, 2010 by ET

First letter was from our university president, explaining that in light of the recent financial crisis, we have to follow the new budget plan and reduce the salary by 5.4%.

Second letter was from my daughter’s school, explaining that in light of the recent financial crisis, they have to follow the new budget plan and increase the tuition by 5%.

What an ironic world.



Converting ISBN13 to ISBN10

January 28th, 2010 by ET

I need to convert a bunch of isbn numbers from the 13-digit format to the 10-digit format.

Figured out the algorithm, and implemented the following subroutine in PERL.  It should be fairly simple to port it to other languages.

sub isbn1310{

my $isbn13=shift;
my @isbn13=split(//,$isbn13);

my $sum = ($isbn13[3] * 10) + (9 * $isbn13[4]) + (8 * $isbn13[5]) + (7 * $isbn13[6]) + (6 * $isbn13[7]) + (5   *   $isbn13[8]) +
(4 * $isbn13[9]) + (3 * $isbn13[10]) + (2 * $isbn13[11]);

my $mode = int(($sum / 11) + 1);
my $last = (11 * $mode) - $sum;
if ($last == 10) {
$last = “X”;
} elsif ($last == 11) {
$last = 0;
}

my   $isbn10=”$isbn13[3]“.”$isbn13[4]“.”$isbn13[5]“.”$isbn13[6]“.”$isbn13[7]“.”$isbn13[8]“.”$isbn13[9]“.”$isbn13[10]“.”$isbn13[11]“.”$last”;
return $isbn10;
}



Computing Power Skirmish

January 6th, 2010 by ET
I have to make some heavy computations these days.  It gives me a chance to compare the computing power of my two computers.
On both machines, I have the same version of MySQL.  The program, written in Perl, conducts some complex calculations based on MySQL data.
skirmish
Dell-Mac Skirmish
It is interesting to observe that my Macbook Pro actually performs better than my Dell Server.  The above figure shows 5 random sampling points, at which I count how many data records have been processed since last sampling.  Macbook constantly beats Dell.
Here are the specs:
Dell:
Dual Quad-Core Xeon CPU 2.33GHz, 32GB Memory, 1T HDD, Windows 7 64 Bit
Macbook Pro:
Core 2 Duo Intel CPU 2.8GHz, 8GB Memory, 500G HDD, Snow Leopard 64 Bit
Due to the nature of the program, only 1 CPU-Core can be used, this may explain the disadvantage of Dell. (Although it has 8 cores, 4 times that of the Macbook Pro.)
UPDATE:
A few more hours of data keep supporting the advantage of Macbook:

dellmac



Fully Utilizing My Computing Power

January 5th, 2010 by ET

Before tweaking MySQL: it used 5% of the CPU and 250MB of the memory.

After tweaking, it uses 94.3% of the CPU and 2.33GB of the memory.

I could increase the memory use even more if I needed it. :-D

screen-capture9



Join Multiple PDF files to a Single One on Mac

December 28th, 2009 by ET

I downloaded an ebook, it contains hundreds of one-page pdf files.  I certainly don’t want to upload all of these one-pagers to my Kindle. To concatenate these files, there is no simply and easy way.  Commercial software packages are available from $14.00 to 20Euro.

A simply perl hack does the job:

  1. Install the perl module:
    perl -MCPAN -e 'install("PDF::Reuse")'
  2. Create a perl program, call it “catpdf.pl”:

    use strict;
    use PDF::Reuse;

    prFile(”output.pdf”);

    for(@ARGV) {
    prDoc($_);
    }

    prEnd();

  3. To concatenate, call it in two possible ways:
  • perl catpdf.pl a.pdf b.pdf, or
  • perl catpdf.pl *.pdf

————–

As a side note, it is really easy to concatenate mp3 files on mac, just do:
cat *.mp3>output.mp3



Avatar

December 24th, 2009 by ET

The most memorable sentence, by the Colonel: “We will fight terror with terror.” It sounds so familiar. LOL.

If you have watched “Brave Heart”+”The Last of the Mohicans”+”Minority Report”, you pretty much miss nothing.

Overall, it is still a good movie.



Time is the Coin of Your Life

December 7th, 2009 by ET

time_is_the_coin_of_your_life_you_spend_it_do_not_allow_others_to_spend_it_for_you-carl_sandburg-480x360-20091207



RIP: Dr. Tsien Hsue-shen (Qian Xuesen)

November 1st, 2009 by ET

Dr. Tsien Hsue-shen (also spelled as Qian Xuesen) passed away yesterday.

To me, he is as legendary as John Nash. A movie based on his life would also be highly appropriate named “A Beautiful Mind”.

qian

Interestingly, both Nash and Tsien were affiliated with MIT.  It was 2008 when I last visited Hang Zhou, the hometown of Tsien, I visited the memorial museum (called Qian King Temple) dedicated to Tsien’s ancestor Qian Liu.  I found Tsien’s Certificate of Master of Science, conferred in December, 1936.  The design hasn’t changed a bit for so many years.  It looks exactly the same as my certificate which I got in 2006, almost 70 years after Tsien got his. I cannot express how proud I was while looking at that certificate.

Tsien is a very typical Chinese scientist, smart, hard-working and humble. He kept a very low profile despite his great achievements.   Great achievements comes with great social responsibility, he sets a great example for anyone who cares to call himself/herself a scientist.



Sleepy

September 21st, 2009 by ET

screen-capture8



BibTeX Title Capitalization (Uppercase) Tool

August 26th, 2009 by ET

I type my BiBTeX entries carefully, but different journals may have different requirements for capitalizing paper titles.

Some would like a plain format, like
Some, Author, 2009, “Capitalizing BibTeX titles: A simple tool,” Science, 110(1), 1-20.

Some Bibtex class files may automatically lowercase all words after the first, so the title looks like:
“Capitalizing bibtex titles: a simple tool,”

To make the title correct, we can add curly brackets, and change the title as:
“Capitalizing {B}ib{T}e{X} titles: {A} simple tool,”

This helps to address the issue, but what if a journal requires all first Characters to be capitalized? like this:
“Capitalizing BibTeX Titles: A Simple Tool,”

It is not hard to write a program to capitalize all words, but then there are complications, like the following case:
“Capitalizing BibTeX titles for Some Journals: A Simple and Intuitive Tool,”

In the above example, “for”, and “and” should not be capitalized.

In another example,
“Capitalizing BibTeX titles for Some Journals: Vote For a Solution,”

The second “For” should be capitalized, but “a” should not be capitalized.

So some intelligence is needed to convert the titles. That’s why I wrote this tool that correctly capitalize the titles.

The location of the tool is: http://blog.mikezhang.com/dcolumn/bibcapital.cgi.

There are some example entries in the box, just click “submit”, see how it works.

To process your file, simply copy and paste into and from this text box.

Again, this tool is offered as is. If you find it useful, that’s great. If you have problems with it, please talk to my friend Feng Zhu, he helped me to debug this tool, I’m going to hold him responsible for additional bugs.


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