Lorenzo Pasqualis

Installing rvm on Lion OSX

lpasqualis@gmail.com (__LP__) — Fri, 27 Jan 2012 20:34:17 PST

If you tried to install RVM on Lion OSX you probably ran into some problems.

The "official" command to use to do the installation works just fine:

$ bash -s stable < <(curl -s https://raw.github.com/wayneeseguin/rvm/master/binscripts/rvm-installer )

What doesn't work is when you try to install say Ruby 1.9.3 from source.

$ rvm install 1.9.3
Fetching yaml-0.1.4.tar.gz to /Users/lorenzo/.rvm/archives
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100  460k  100  460k    0     0   126k      0  0:00:03  0:00:03 --:--:--  138k
Extracting yaml-0.1.4.tar.gz to /Users/lorenzo/.rvm/src
Configuring yaml in /Users/lorenzo/.rvm/src/yaml-0.1.4.
Compiling yaml in /Users/lorenzo/.rvm/src/yaml-0.1.4.
Installing yaml to /Users/lorenzo/.rvm/usr
Installing Ruby from source to: /Users/lorenzo/.rvm/rubies/ruby-1.9.3-p0, this may take a while depending on your cpu(s)...

ruby-1.9.3-p0 - #fetching 
ruby-1.9.3-p0 - #downloading ruby-1.9.3-p0, this may take a while depending on your connection...
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100 9330k  100 9330k    0     0   286k      0  0:00:32  0:00:32 --:--:--  349k
ruby-1.9.3-p0 - #extracting ruby-1.9.3-p0 to /Users/lorenzo/.rvm/src/ruby-1.9.3-p0
ruby-1.9.3-p0 - #extracted to /Users/lorenzo/.rvm/src/ruby-1.9.3-p0
ruby-1.9.3-p0 - #configuring 
Error running ' ./configure --prefix=/Users/lorenzo/.rvm/rubies/ruby-1.9.3-p0 --enable-shared --disable-install-doc --with-libyaml --with-opt-dir=/Users/lorenzo/.rvm/usr ', please read /Users/lorenzo/.rvm/log/ruby-1.9.3-p0/configure.log
There has been an error while running configure. Halting the installation.

What is the deal? The issue is clear if you look at the log, however the fix is not so clear:

$ cat /Users/lorenzo/.rvm/log/ruby-1.9.3-p0/configure.log
[2012-01-27 20:08:11]  ./configure --prefix=/Users/lorenzo/.rvm/rubies/ruby-1.9.3-p0 --enable-shared --disable-install-doc --with-libyaml --with-opt-dir=/Users/lorenzo/.rvm/usr 
configure: WARNING: unrecognized options: --with-libyaml
checking build system type... x86_64-apple-darwin11.2.0
checking host system type... x86_64-apple-darwin11.2.0
checking target system type... x86_64-apple-darwin11.2.0
checking whether the C compiler works... no
configure: error: in `/Users/lorenzo/.rvm/src/ruby-1.9.3-p0':
configure: error: C compiler cannot create executables
See `config.log' for more details

An issue with the C compiler. Even though you seem to have gcc installed just fine, it seems not to be able to create the executable. The issue is that you need a non-LLVM version of GCC, which is no longer included with XCode 4.2.
You can solve the issue using:


rvm install 1.9.3 --with-gcc=clang

Which will configure ruby to use clang (a front-end for the C/C++/Objective-C/Objective-C++ programming languages), solving the compilation issue.

Enjoy.

Ruby's ||= operator dangers

lpasqualis@gmail.com (__LP__) — Wed, 25 Jan 2012 21:58:25 PST

The ||= operator in Ruby is a fantastic shortcut to initialize a variable only once. It is used all the time to write something like:

    some_hash = {} if some_hash.nil?

into a much shorter and more compact:

    some_hash ||= {}

However, it is extremely important to NEVER use this operator to initialize a boolean flag this way. In fact, it is tempting to write something like:

    def exists?
        @exists ||= record_exists?
    end

To cache the boolean return value of record_exits?

This code seems to say "if @exits is null, then calculate it and return it; otherwise, return the cached value that we already have".

However there is a fatal mistake here. The ||= operator evaluates the rvalue if the lvalue is nil OR FALSE! That means that this code will end up calling record_exists? every time that @exists is un-initialized (good), but also any time that @exists is false!

Not what you wanted!

So... in general, NEVER use ||= to initialize un-initialized booleans. Stick with:

    def exists?
        @exists = record_exists? if @exists.nil?
    end

Adding to methods of existing classes in Ruby 1.8.x

lpasqualis@gmail.com (__LP__) — Wed, 11 Jan 2012 15:59:38 PST

For an open source project I am working on (more on this later on) I had the need to wrap functionality of existing Ruby classes programmatically without actually having to open up the class and declaratively patch it.

It took a little while to find the magic, but here it is a snippet of code that exemplifies my findings. The sample does the following:

- Grabs an existing class (Test, in this case)
- Changes an instance method to call the old instance method and then do something new.
- Changes a class method to call the old class method and then do something new.

The code is nasty looking for class methods in Ruby 1.8.x, but it works.
If you use Ruby 1.9 there is a cleaner way.

class Test
 def test_instance_method
  puts "original test_instance_method"
    end
    
    def self.test_class_method
     puts "original test_class_method"
    end
    
end

# Add to the instance method

Test.send(:alias_method, :old_test_instance_method,:test_instance_method)
Test.send(:define_method, :test_instance_method) do
 old_test_instance_method
 puts "new test_instance_method" 
end

# Add to the class method

(class << Test; self end).send(:alias_method, 
                               :old_test_class_method,
                               :test_class_method) 
(class << Test; self end).send(:define_method, 
                               :test_class_method) do 
 old_test_class_method
 puts "new test_class_method" 
end

# Test

Test.new.test_instance_method 
Test.test_class_method

Let's see what it does:

$ ruby test.rb
original test_instance_method
new test_instance_method
original test_class_method
new test_class_method

It worked!

In Ruby 1.9 I could have used define_singleton_method, but in my case it needs to work in Ruby 1.8.x so I have to live with that nasty thing.

Synchronizing Your Computers Painlessly

lpasqualis@gmail.com (__LP__) — Fri, 02 Dec 2011 12:49:38 PST

I have been a long time user of Dropbox, and I am very fond of it. If you are not familiar with it, Dropbox is a FREE service that allows you to share a directory on multiple computers and it also functions as a cloud backup service for that directory and as a revision control system for it too.

You signup for DropBox and install their client on your computers and mobile devices. Then you choose a directory to share and voila', from that moment on any file that you copy to that directory will be synchronized across all your computers and devices completely transparently and without using much resources on your machines at all. DropBox will keep a copy in the cloud, and will also keep many revisions so you can always go back to something that you deleted or changed by mistake.

I use it all the time for my photography when I am on the go for multiple days. I bring a few memory cards just enough for a day of shooting. At the end of the day I drop the photos into my Dropbox directory on my laptop and I clean my memory cards and keep on shooting. When I get home after several days the photos are not only on my laptop, but also on all the other computers I have, and a copy is safe on the DropBox servers too.

I also use DropBox for sharing configurations across my machines and keep them all in sync.

I use mostly Mac OS these days; at work I have MacBook Pro, and at home an iMac. I work in terminal all the time, and quite often I make adjustments to my ~/.profile to add paths, change my prompt, set configurations, etc. I also have a set of scripts that I wrote that I use all the time.

I like consistency, and I hate making the same changes on many machines to keep the same configuration between work and home.

To solve this problem, I added this line on my .profile file on all my Macs:

source ~/Dropbox/lorenzo/shell_settings

Then I put all the settings that I like to share in the ~/Dropbox/lorenzo/shell_settings file, which for me looks something like this:

alias dir="ls -l"
PS1="[\u@\h:\w]\$ "
export PATH=$PATH:~/Dropbox/bin/tools

And voila', on all my machines I now have "dir" do what I expect, my prompt look pretty and a handy shared directory where I keep my scripts across my machines. The scripts are on Dropbox too, and in this case I not only get the benefits of having the same version everywhere, but it also functions as source control for any modification I make over time.

Dropbox is available on Windows, Mac, Unix and mobile devices and.... it is FREE for 2Gb. I pay for 50Gb which is only a well worth $99/year. You have got to try it, it will change the way you deal with multiple computers and it will make thumb drives feel like prehistoric technology.

Google Calculator

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 12:48:06 PDT

Google is not only a search engine.

Did you know that you can use Google as a unit/currency converter and multi-unit/currency calculator?

Examples:

Forgot how many cups in a teaspoon? Try typing "1 cup in tsp" as a Google search to get an answer.
Do you want to know how many seconds in a year? Try to search for "year in seconds".
Do you want to know the area in square feet of 3 meters * 1 cm ? Try "(3 m * 1 cm) in feet^2"
Do you want to know how much is a British pounds in dollars? Try "1 British Pounds in USD"
Do you want to know how much is a dollar in whatever currency they have in China? Try "1 USD in Chinese money"

Splitting of the Red Sea

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:41:43 PDT

My latest sculpture. I found this piece of wood in the woods. It had been there probably 5 years or so. Then I dried it for 3 years in my workshop, and finally cleaned it, sculpted it and made it into this piece.

DreamBox Learning Shipped Today!

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:55:47 PDT

Today we officially launched DreamBox Learning K-2 Math, a Math Learning Game that is now available to help kids learn, enjoy, and excel at math!

Every day we receive fan mail from parents and teachers who tell us heart-warming success stories of kids playing DreamBox, from struggling learners to advanced achievers. The combination of our individual adaptations, in-depth math curriculum, and game-like adventures is working! We are actually “doing good” for the world! And of course I’ve seen how much my own children like it and learn.

Here is a product tour video! Check it out!

Here are a few ways to help us build the buzz:

• If you have kids in the right age group, please do try DreamBox
• Recommend it to your friends (and earn free months in our invite-a-friend program!)
• Write about it to your local Mom’s group or PTSA group
• Give it as a gift
• Blog about it
• Forward this information to anyone

Starbucks Speaks Italian, or not...

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:56:15 PDT

It seems like writing Italian phrases and words is now considered somehow a "touch of class" in many coffee stores, restaurants and other commercial establishments. I find it flattering and I have no problems with it. I share this love for the Italian language.
On the other hand, I find it embarrassing for the people or corporations that spend time and money to write enormous phrases in Italian on their precious wall space when the phrase itself contains elementary school level spelling mistakes. Ouch!
Now, I do not claim that my English is perfect; far from it as you can see. However, rest assured that if I had to write a huge four words phrase in any language in my hypothetical coffee shop, I would make pretty darn sure I got the spelling correct! Especially if I use such word to try elevating the elegancy of the place!
Now check out this "thing" that I saw, and took a picture of, in a Starbucks near where I live:

This phrase is about 6-7 feet long on a wall, and it takes very little to find out that the spelling is WRONG. I could understand the mistake if it was hard to verify... however, it takes only 30 seconds to find out that there is a problem. The easiest way is to search for this exact phrase in Google. At the time I wrote this post there were only 8 results for this, all from pages with spelling mistakes, and Google even offers a different spelling. Note how it says: Did you mean: "La macchina del caffe". Well, click on that link and now you get 4,000 matches. Not bad. A quick look at the italian dictionary will confirm that "Macchina" is the correct spelling! Not the huge wall-inscribed "machina", which is an embarassment for Starbucks. YUK!

The children know

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:56:35 PDT

A quote that inspired me.

"The children know. They have always known. But we choose to think otherwise; it hurts to know the children know. The children see. Thus we conspire to keep them from knowing and seeing. And if we insist, then the children, to please us, will make believe they do not know, they do not see. Children make that sacrifice for our sake - to keep us pacified. They are remarkably patient, loving and all-forgiving. It is a sad comedy: the children knowing and pretending they don't know to protect us from knowing they know."

( Maurice Sendak )

Conception of a Bird

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:42:10 PDT

This is my first Driftwood sculpture. I called it "Conception of a Bird". It represents a frozen beginning stage of the forming of an image or idea of a bird in the human mind.

Title: Conception of a Bird.
Wood: Unknown Driftwood. Possibly some kind of root.
Base: Peruvian Black Walnut. Turned.
Finish: Natural Danish Oil & Beeswax.
Time from start to finish: About 15 hours in the span of several weeks.

Driftwood and the LuRon method.

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:42:49 PDT

Driftwood is wood that has been washed onto a shore or beach, of a sea or river, by the action of winds, tides or waves. It often appears white, weathered and rotting. For some people it is simply junk, and often a nuisance. For others it contains a piece of art. As anything else in life, it all depends on what you can see in it. Sculptors see beautiful shapes in stone or other materials; similarly a driftwood artist sees the beauty in the forms of naturally shaped and weathered wood.

Hard to believe for most, but inside most pieces of driftwood lays a beautiful piece of wood with fantastic grain and colors. Lucile Worlund discovered this fact about 40 years ago and created an art form. She was so fascinated by the interesting shapes of driftwood and its inner beauty, that she defined a process to transform it into sculpture, and trademarked unde the name of "LuRon method".

Her method is aimed to remove the weathered part of the wood, scrape and cut off all the dead cells and rotting material, polish it, burnish it with deer antlers and finish it with beeswax or penetrating oils and mount it for display. The result is a clean piece of solid wood which beautiful and complex shape is often the result of the natural sculpting process enhanced by the artists, and which grain, patterns and colors are simply magnificent. The job of the driftwood artist is to find a piece with potential, discover the inner beauty and enhance it to transmit an emotion or a concept. Some examples of LuRon-method sculptures can be seen here.

The method is extremely natural, and it can be carried using simple tools, although you can get very sophisticated. The process is almost a form of meditation that brings you closer to nature and leads you to a journey into the inner beauty of raw natural materials. It’s almost a demonstration of how anything can become a wonderful piece of art, if polished by the hands of a skilled artist.

Driftwood assumes amazing and complex shapes. I have a theory why that is so common. You have to know that most wood has internal tension, and that tension sometimes is very strong; in fact it’s not uncommon that, when you cut a thick piece of wood, the wood snaps or binds the cutting blade as the result of release of that tension. As a piece of driftwood rots from the water or weather exposed layers, it stays solid in the inside. The tension of the inside solid material, overpowers the strength of the rotting material, and starts contorting the whole piece into very interesting shapes.

The LuRon method is native of the Pacific Northwest. The official website for the Northwest Driftwood Artists association, founded by Lucile Worlund, is http://www.geocities.com/northwestdriftwood/. You won’t find much information on this method on the net or in books. The only book that I know talks about LuRon is Driftwood Sculpture: From Finding to Fine Finishing (Paperback), and it’s not easy to obtain. I ordered a copy from amazon 2 months ago, and still waiting for it.

I am currently taking a class on the LuRon method. If you want to know more about it, feel free to ask. I may publish more details.

How long is the present moment?

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:55:02 PDT

The only moment that you can truly experience is the present, or NOW. You can't live in the past, you can only remember it, and you can do it only NOW. You can't live in the future, you can only plan for it, and you can do so only NOW. The present, or NOW, is the amount of time that can use information accumulated in the past or plan for the future.

Practically, the only time in which you can truly actively do something is NOW. Philosophically, it is often said that it is truly important to enjoy NOW, and make the most out of it, experience the present, grasp the moment. The poet and philosopher Horace expressed this concept in a Latin poem with the phrase “Carpe Diem”, or seize the day.

This is all good, and I do agree with that statement; entire books have been dedicated to this subject. A popular one is “The power of now”.

One question that I have been dwelling with is: “how long is the perceivable NOW”? If you think of time in mathematical terms, NOW is an infinitesimal length of time. It is similar to a mathematical point, which is more of a concept than a physical and humanly perceivable reality. A mathematical point doesn’t have a physical size and doesn’t have a physical shape. It’s simply a concept, with no physical counterpart. It is a simplification. An ideal.

Think about a visible line. A physically visible line is composed by an infinite number of theoretical mathematical points. Similarly you can think of a perceivable length of time as composed by an infinite number of theoretical and infinitesimal points in time, or NOW moments.

I wondered how long is a "more useful NOW”, that is, I wonder how long is the smallest stretch of time that one can truly dwell in.

Going back to the analogy with a line, my question is similar to asking: how long is the shortest visible line? How big is the smallest visible detail of a picture? How far apart must two visible lines be to be perceives as two separate lines? What is the smallest pixel of a hypothetical display, to be able to represent the smallest perceivable detail of an image?

Concentrating on the question about the pixel, I am assuming that there is a certain critical size of pixel. If you made pixels any smaller than that critical size, the human eye wouldn’t be able to perceive any additional detail. This would make any pixel size smaller than the critical size simply not useful for better representation of an image as perceivable by the human eye. That critical size exists, and has been measured, and it depends on the distance from the eye to the observed image. That critical size is accurately (and absolutely) expressed as an angle; for purpose of discussion, and to give you a simpler example to grasp, if you are looking at a monitor from 20 inches distance, the critical size of a pixel is 1/530” (Source: http://www.clarkvision.com/imagedetail/eye-resolution.html).

Going back to the concept of time, here is some interesting research information about human perception of time:

How long does the ‘present moment’ last? In the case of humans, it has been found that sound pulses separated by more than 3 seconds can no longer be grouped into pairs because they fall outside the span of attention. This represents the maximum interval of time that is simultaneously present for subjective evaluation – a kind of attention span bridging past and future events.
How finely can we divide our little 3-second lives? The shortest perceivable time division – sensory psychologists call it the fusion threshold – is between 2 and 30 milliseconds (ms) depending on sensory modality. Two sounds seem to fuse into one acoustic sensation if they are separated by less than 2 to 5 milliseconds. Two successive touches merge if they occur within about 10 milliseconds of one another, while flashes of light blur together if they are separated by less than about 20 to 30 milliseconds. [Source: Nick Herbert, Elemental Mind, Dutton, 1993].

The conclusion is that the critical length of perceivable time is represented by the fusion threshold, that is between 2 and 30 ms. The span of time that you truly live in the present moment is about 3 seconds, and is somewhat of the bridge between present and future. More phylosophically one could say that we slide through life on a 3 seconds surfboard, which carry us across all moments of our lifetime. Your existence is all concentrated in these 3 seconds; anything else is either a memory or a plan.

Something to think about…

Assumptions are hiding places for the truth.

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:56:55 PDT

This morning I walked in a conference room a bit early; while I was waiting for my collegue to join, I picked up a book that was sitting on the small coffee table at the center of the room. That book has been there for many months. It showed up in the conference room in the same period when the company was organizing Japanese classes for the employees. The title contains the word "Japanese", it has has colors similar to a book called "Japanese for Busy People" that I saw circulating around during the Japanese classes period.

I spent many hours in that conference room, stared at that book many times, and every single time I thought "I wonder who lost this Japanese language book". Many times I meant to look at it, but never did.

When I picked it up today I didn't realize that it was NOT a language book, at all! I even looked at a bunch of pages before truly stop and read the cover page, where the title proudly announced that my big assumption was wrong. The title on the cover is "The Big Bento box of Useless Japanese Inventions". The book is sort of a collection of strange and useless Japanese inventions.

Here is what happend: I saw "Japanese" on the cover, it showed up in a period where Japanese language classes where in mind, it has similar colors to a Japanese language text book... and all this information created the notion in my mind that it was Japanese language text book. I assumed it. For months! I started at the cover, without *really* seeing what it said. I was looking at the facts, without truly seeing the *facts*.

This was a small demonstration, for me, of how the reality that we live in is what we decide to see, and not what it is. It is a small demonstration on how the truth sometimes can be right there screaming at us, and we simply don't see it.

Our marvelous brain associates images and concepts with our knowledge, and makes up the rest of the reality working with associations and pattern matching. It makes up all that reality that we don’t stop and truly observe. This allows us to move faster, and it works most of the time. Sometimes it doesn’t work, and it pushes us into making unverified assumptions. In my engineering work I found that 99% of the errors I make are lurking into these unverified assumptions.

So, here is a piece of advice. Whenever you are hitting a wall and you can’t find where “the problem is”, look at all the assumptions you made and verify that they are correct. Remember to *TRULY* look at the assumptions. Don’t just skip over them. Anytime you skip over an assumption you could be skipping over the issue that is creating the problem that you are trying to solve. The truth is usually hiding in one of the assumptions you made.

I told this story to a colleague, and he mentioned a joke that has a lot of truth in it; I find it useful to help reminding me to never assume: "ASSUME makes an ASS of U and ME".

Thinking mathematics, acting art.

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:57:24 PDT

It was 1983 when the movie WarGames came out. It was that movie, believe it or not, that fascinated me to the point of changing and shaping my life forever. If you watch the movie today you’d find it cheesy and almost embarrassing, but at the time, when I was 11, it completely captivated me.

Around that time my aunt was buying an encyclopedia. As gift from the publisher she received a small home computer, which was quiet fashionable in the mid ‘80s. It was an Acquarious, one of these many unknown failed attempts that never made it big. A home-computer with rubber keys, an overheating problem and a cassette player as a storage device; one of these unfortunate competitors of the Commodore C64, that at the time dominated the low-budget computer market.

Since my aunt was (and still is) completely unable to deal with technology, she gave it to me. I was 12, and that cheap cheesy machine started it all. I skipped the stupid little games that came with it, and started learning the simple Basic Language of the built-in interpreter. Almost immediately I decided that Basic was not enough for anything serious, and I started studying and coding with Assembly. On home computers in that era you would typically code in assembly with a bunch of "poke", "peek" and "data" Basic instructions that would load the machine codes directly into memory for execution. Scary, but it worked.

Not long after that I purchased a used Commodore Plus4, which was a heck of a lot more powerful and fun to use. It came with a word processor and a spreadsheet built in, and an excellent Basic interpreter. Painfully saving money week by week, I bought a 5" disk drive, and kept coding away in Basic and Assembly. Eventually I moved to an Amiga 1000 (which I hated), and not long after to a IBM 8088. From there I kept upgrading with the various INTEL chip generations (V20, 8086, 286, 386, 486, Pentium, etc...). I worked on a first software development project for a customer when I was 14, in order to raise some cash to buy new and better technology (and go to movies and have fun), and never stopped since.

Well, to make a long story short I have been writing software everyday for well over 20 years now, and I grew up coding.

Probably due to this growth so close to technology, I felt at times that I lived in a world that was border-line with mathematics and perfect sciences. I often wrongly assumed that there was always a best way to solve any solvable problem and that it was always possible to identify not solvable problems and work around them with approximations. This sometimes led me to assume that we live in a time where science can find answers to most problems.

Well, I am changing.

I experience everyday that trying to find the perfect answer or ideal solution is impractical and unnecessary. The more I mature in age and experience, the more I realize that practical and achievable solutions are often found thanks to the experience and intuition of the engineers, and not thanks to some well known procedure that can be efficiently thought to others. For this reason, in general, the more experienced an engineer is, the better the solutions are and the quicker they come to be.

This makes software engineering more a form of art than a perfect science. Even if the basis of engineering is in well defined theory and theorems that have been proven mathematically, the success of the application of such theory and theorems in the real world is completely reliant on the skills of the people that do the work. No book can teach you how to apply theorems and theory, no book can truly and practically teach you when to pick an algorithm instead of another. Books and theories can give you an idea, but the efficient and practical application is really a form of art and a product of intuition. Almost a trade.

In this context, I define "art" as the application of procedures and theories based on experience and the artist unique perception of the world, to solve practical problems in a universe governed by laws that we don’t completely understand.

I am always amazed when I realize how much art is involved in any engineering filed, and how much engineering and science is necessary in any art field. For example a painter or a sculptor that wants to excel in the painting or sculpting of the human body, needs to study human anatomy in details and became an expert in the functioning and interactions of the body muscles and bones. Only doing so gives the artist enough knowledge to be able to visually recreate something that is close enough to reality to be considered pleasant and just right to human perception. Leonardo da Vinci knew this. Given that not much material was available he did first-hand research on human anatomy, risking his life and reputation in the process.

On the other hand, the practical application of medicine and surgery is so much based on art, steady hands, intuition and experience that is barely a science. Yes, true, surgeons need to be trained and know the theory very well, but the actual application of the theory and the process of performing a surgery is really a form of art that is susceptible to human error and miss-interpretation of cause and effects. Much like sculpting and painting! Also, a good doctor or a good surgeon is usually able to create a trust and a connection with the patient, which improves the success rate of medical treatments and surgery. This makes doctors very close to artists, in the sense that they are able to direct human perception in a particular direction, beneficial to the achievement of the end-goal.

I am always amazed that engineering and trades, science and art, mathematics and intuition, are so close in nature, if not one and the same, with a different accent and presumptions.

Sharp woodworking tools.

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:58:00 PDT

If you are into Woodworking, wood turning or woodcarving, having sharp tools is a must. The tools that you buy are almost always useless out of the store; you need to remove the factory's grind marks on back and bevel, and polish the back and the bevel appropriately.

Wood chisels that you buy at the Home Depot or Lowes are low-quality, and some hard work is required to make them somewhat useful. Even the most expensive carving chisels bought in the best stores require at least some leather stropping with polishing compound to be truly sharp.

The edge of woodworking cutting tools (especially carving) requires stropping often during the work, and sharpening periodically when needed; knowing how to sharpen a blade is not an option for anybody that wants to use a blade for woodworking. If you don't do it, you will always think that using a chisel is too hard for you and you will give up. A sharp blade cuts cleanly and well and it is a pleasure to use. A dull blade is useless.

I have been interested in sharpening techniques for years now, and I experimented and practiced with water & oil stones, sandpaper, high speed grinders, low-speed grinders, flat grinders and curved grinders. It takes time to learn what a sharp blade is, and even longer to finally be able to create one.

Like all fields of engineering, it's both an art and a science, even with expensive equipment the difference between a sharp blade and an "almost" sharp one is in the artistry and experience of the sharpener. That said, with a bit of practice, anybody can do it.

What "sharp blade" means, depends on the application. If you are splitting logs, you don't need a very sharp blade; actually Wood Splitter's Mauls are not sharp at all. They only need to get between the fibers of the wood and push it out, splitting, and not cutting. A sharp blade tends to "catch" the grain, not splitting the log. A maul breaks the log along the grain of the wood.

On the other side of the spectrum, when you carve wood with chisels, you need a razor sharp blade. When I say "razor sharp" I am not making an hyperbole! I actually mean it. You should be able to shave with a carving chisel, if you wanted to. I test my carving chisels on the hair on the back of my hand. I consider a carving chisel sharp when I can cleanly shave hair off it with the blade (don't try this at home).

Turning chisels are a different beast. They need to be sharp, but they also need to be very strong given that they see a lot of wood very quickly. For this reason, turning tools are not something that you would define "razor sharp". The bevel is too steep to cut hair, but is still sharp because it needs to cut cleanly and quickly.

If you are interested in an in-depth description of various tools, what sharp means for each tool and how to sharpen them by hand, I strongly suggest a book titled The Complete Guide to Sharpening, written by Leonard Lee. The book is a bible, and if you are interested in sharp tools, it's a must have.

Unfortunately sharpening by hand is a very time consuming process, and when the time to be in the shop is little, you don't want to spend most of it making your tools sharp and no have any time to actually use them (I've done it). For this reason my personal quest has been to obtain highly sharp tools as quickly as possible.

The first attempt was with high-speed grinder, such as the cheap models that you buy at the Home Depot. If you buy one, throw away the gray wheel that comes with it. It's worthless. Buy a white or pink one. Even having done that, I realized soon that these were not very useful except, perhaps, to sharpen lown-mower blades or quickly touch up turning tools.

The second step was to try with the water stone approach. Years ago I purchased a few Japanese water stones and honing guides. The results were awesome. With practice I was able bring cabinet chisels to a near-mirror polish with razor-sharp edges. The problem here is that it would take hours of hard and tedious work to go from a store bought chisel to a precision cutting instrument. Who has time for that? Not me.

My third step was to buy a Tormek slow-speed grinder. Awesome machine, at the time it was the top of the line. You can buy all sort of additional attachments and jigs to sharpen all sort of tools, from pocket knifes to swords, from carving chisels, to cabinet scrapers. This machine is great to reform a bevel of any shape, change the angle of any bevel, and bring tools to a decent sharpness and to do most of the time consuming steel removal. The stone works quickly and the jigs are fantastic.

With Turning tools and most shop tools that’s all you'll ever need, and probably more.The issue with this system is that it doesn't work very well for carving tools. I mean, it sharpens them, but if you want a great edge you need to finish the tools off on a water stone: the grinding wheel is too rough, even if you use the optional grader to make it finer. The other problem is that the leather honing wheel round edges too easily. The final problem is that, like every wheel grinder, it leaves you with a hollow bevel. This is good for turning chisels, but is bad for carving chisels. Anyhow, this machine is a good thing to have in a wood shop.

Recently I also noticed that Jet came up with a very similar machine. They took the Tormek and copied it, adding a couple of interesting features. I haven't tried one, but you may want to check it out. Frankly I am kind of upset that Jet can so bluntly copy Tormek products to that extent, and get away with it.

Anyway, since I am interested in woodcarving, and since I have a collection of very expensive Pfeil Swiss-Made gauges that I don't want to ruin on a grinding wheel, I decided to invest in a Lap-Sharp 200 sharpening system.

This is the Rolls Royce of sharpeners. It is sold only in a few stores, and it is expensive, but the results are amazing. At my first attempt with this machine, I was able to bring a carving spoon gouge, previously re-shaped on the Tormek to a 25 degree bevel, from a bevel with grind marks, to a polished near-mirror surface and a razor-sharp cutting edge. The difference between "before" and "after" using the LapSharp was amazing. The Lap Sharp created the sharpness required for a very clean cut.

The Lap-Sharp uses hig quality abrasive disks available in grits from 120 micron for fast metal removal, to 1 micron for final polishing and honing. Stropping while carving is not even necessary anymore. I keep a 1 micron abrasive disk mounted on the Lap Sharp, and when I need to strop I just take the gouge for a quick touch up on it. That's all I need. Quick, fast and easy.

Despite the fact that the system has a jig for gauges, I was able to do my carving gouges sharpening by hand, with amazing results. The carving/tourning jig is still good to have because it comes with a handy mount that can be used to hold an accurat angle.

In conclusion, if you are serious about sharpening, and if you are into woodworking, turning and carving, the ideal setup is to have a both a Tormek and a Lap-Sharp, one next to the other.

You use the Tormek for the tool's initial heavy metal removal and bevel forming (if necessary), and the Lap-Sharp to bring the hollow bevels to a flat surface, and to bring any bevel to a mirror finish and perfectly honed quality.

If you can't have both, and you need to pick, buy a Lap Sharp. You will love it.

A tribute to Ian Norbury

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:58:17 PDT

As I wrote in my profile, I love to build things. One of my passions is for sculpture, in particular wood sculpture, or carving in the round. I have alot to learn in that area, and with a demanding job and a family I do not enough time to really dedicate myself to sculpture as much as I'd like.

Regardless, I keep collecting carving tools and I try to carve out some time for my passions (pun intended). From time to time I work on a new piece with a hope that some day I will be able to dedicate more and more time to this art that so much reminds me of my origins.

Anyway, this post is not about me; it is a small tribute to the best wood carver that I know about. His name is Ian Norbury. Visit his website and enjoy. If you are like me, your jaw will drop and you will wonder how a human can possibly make wood look like he does. I think the answer is: hard work and passion. Please, judge for yourself.

Note his Harlequines. Note the different colors. You think they are painted? No, they are individually inlayed wood diamonds! Can you imagine the amount of work required to do that?
Note the smooth surfaces and the proportions of his sculptures, the dynamic of the poses, the perfect marriage between realism and beauty that he is able to extract from raw pieces of wood.

If you want to give somebody a good gift, buy Ian Norbury's book "The Art of Ian Norbury: Sculptures in Wood" (ISBN 1565232224). A wonderful showcase of his art that anybody would love to have on their coffee table.

Traffic & The First Rainy Day.

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:58:36 PDT

When I was in Italy I observed how every first day of rain after many sunny days always had the effect of dramatically increase traffic. This was especially evident after long sunny periods in summer; after all that sun, the first rainy day would have the good effect of producing that sweet aroma of dust blown off the road by the rain drops, and the bad effect of increasing traffic in a unbelievable manner.
At the time I explained this phenomenon thinking that, during sunny days, Italian people drive their scooters or motorcycles, and when the rain comes they have to take the car to stay dry. Since many people drive two-wheelers, the explanation was somewhat logical. Another additional explanation was that car accidents are more frequent due to slippery roads. Since car accidents tend to slow down traffic, that was also a good explanation. The reason accidents are more frequent the first rainy day is that roads, since they have not been washed by the rain for a few days, tend to be covered in dust; when it finally rains, that dust produces a slippery coating that makes driving hazardous.
When I lived in Switzerland for a few months, I observed the same thing. The first day of rain after a few days of sun, produced a great increase of traffic. In Switzerland I don’t recall many motorcycles and I never saw any traffic jams caused by car accidents.
When I moved to Seattle I noticed the same phenomenon. Again, people don’t tend to drive motorcycles all that much around here. Some people do ride bikes but, since it rains most of the time anyway, they don’t seem to care if they get wet.
This morning I witnessed this phenomenon again. It had been sunny for several days and today it rains. The traffic is horrible, but there were no accidents; just lots of cars.
I have no explanation. Can somebody tell me why the first day of rain, after long stretches of sun, causes the traffic to get so bad everywhere in the world?

How to setup a Podcast in less than two hours.

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:58:51 PDT

What is Podcasting? In a nutshell Podcasting is a form of Syndication where a publisher records content into Multimedia files and makes it available to the world for listening or viewing. A Podcast is published with an RSS feed containing Podcast specific tags to describe the type and location of the multimedia files, the title, the genre, copyright and license information etc...

A listener or viewer subscribes to Podcasts with software such as iTunes. Once subscribed, the software downloads the multimedia content into a PC or device able to play it. Often the content is in the form of MP3 files for audio Podcasts and the device is an MP3 player such as iPOD. For a video Podcast the content is most often published in the form of MP4 files and the device is an MP4 player such as a Video iPod.

If you use iTunes, you may want to check out iTunes Essential tips for podcast lovers. It will give you all the information you need to understand podcasting the iTunes way.

While the concept of Podcasting has been around as early as 2000, it was only around the end of 2004 that it took off and thousands of Podcasts started to circulate.
For more general information on Podcasting take a look at Wikipedia under Podcasting.

In this article I’d like to describe how you can create an Audio Podcast in less than two hours mostly using free tools. This article describes one way of doing it, but there are many other ways. Let’s get started...

First of all, you need audio or video files with content you want to publish! Assuming you want to publish Audio files and that the content of the Podcast is a speaker talking about something, there are two main ways to generate this content.

The first one is to record the audio with a microphone and a recording device that allows you to generate good quality sound files.

The second option is to type the text with a computer and have a Text To Speech software read it and generate the audio file for you. As a Text To Speech engine I recommend "TextAloud", by NextUp. It costs only a $30 and if you purchase some of the advanced natural voices (another $35) the quality is decently good. You may disagree, so you should evaluate the product and find out if you like it. At the end of this article you’ll find the link to an MP3 with the content of this post read by TextAloud using one of the AT&T natural voices. Check it out!

Once you have the audio files you need to host them somewhere. These files can get very big so you need a reliable service that is not going to charge a ton of money for bandwidth in case your PodCast gets very popular. I suggest FREE. You don’t get cheaper than that! Such service exists if you plan on releasing your content with a Creative Common license. Check out www.archive.org which provides hosting for multimedia files for free, and no limits in bandwidth. The setup on www.archive.org is a little strange; for this reason I’ll give you some details to make it easier.

First of all you need to create an account. Go to www.archive.org home page and click on Upload your own recordings in the Audio section. It will ask you if you want to login or join. Since I assume you have no account yet, you must go to "Join" (it’s free, so don’t worry about getting your credit card ready). All you need is an email address, a password and a screen name. Once you are done and your account is created, go back on the main page of archive.org and click again on the "Upload your own recordings". At this point you should already be logged in (if you are not, do so).

The upload page will ask you an identifier for your item. It is basically asking a name for the collection of files you are going to upload. Let’s assume that you want call your collection "mypodcast" (original, huh?). Simply type that into the input box on the upload page and press "Create Item". At this point the collection with that name gets created. After creation the collection is in "check-out" mode; that means you can upload files into it (with FTP or a browser) and describe them. Follow the instructions, describe your files and pick a license type...

When you are done uploading you’ll need to check-in the files in order to make them available to the public. Follow the instructions to do so.
An undocumented (or poorly documented) trick I found. You can always checkout a previously checked-in collection with the following web API:

http://www.archive.org/checkout/mypodcast

You can check-in the collection with:

http://www.archive.org/checkin/mypodcast

You can check the details of a collection with:

http://www.archive.org/details/mypodcast

You can download the files that you uploaded using:

http://www.archive.org/download/mypodcast/filename.mp3

Simple, isn’t it?

If everything went well, you should see your files when you browse your collection’s detail page. These are the URLs that you can use to publish your Podcast.
The hardest part is done! Now you need to create an RSS feed with your Podcast information and the links to the audio files in it. How to do so?

I suggest that you use a combination of Blogger and FeedBurner; Blogger is good to create and manage the Atom feed and FeedBurner to create the RSS feed from the atom feed. Complicated? Not really! It’s actually very simple once you get going and understand the concepts.

First go to blogger.com, create an account if you don’t have one and create a new blog. The instructions are clear and the process easy. Once you have a blog, simply create a post containing, anywhere in the text, a link to any of your audio files hosted on www.archive.org.

Now, go to FeedBurner.com, create an account if you don’t have one and create a feed from the blogger’s blog. FeedBurner has a good Quick Start guide that will guide you in the various steps. You really need to understand what you are doing anyway, so a little bit of reading and trying will only be good.

The important part at this point is that you setup and activate the SmartCast section of the FeedBurner feed settings. That will instruct FeedBurner to add all the Podcast information necessary for iTunes to work with your feed.

Well, you are done! You can just run iTunes and subscribe to your feed! To do so go to the "Advanced" menu and select Subscribe to Feed option. Put in the URL of the FeedBurner RSS feed. That’s going to look something like http://feeds.feedburner.com/mypodcast.

The next step is to make sure people know that your Podcast exists. To do so the best way is to get listed on iTunes. Go to the music store, select Podcasts and look for the “Submit Podcast” link. Go from there… your traffic will explode.

If you want more information on the iTunes requirments for RSS feeds, check out Podcasting and iTunes: Technical specification.

Imagine the possibilities! Now you can have your private radio show with potentially thousends of listeners!! I whish I had this when I was a kid :)

Audio Podcast of this Post

Apple Video iPOD, the 10 minutes user experience.

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:59:12 PDT

I recently bought a 60 Gb Video iPOD.

First of all let me state that I believe the product is a piece of extremely high quality electronics and that Apple really got this one right: the device is slick, attractive, made of high quality materials and works really well. The display is amazing and the quality of the audio very good. The Volume is powerful and you don't have to worry about being in a loud place and try to listen to your music. You can crank it up and hear very well in most conditions...

...I could go in many details but you'll find much better product reviews elsewhere and I am not going to attempt writing one here. In this post I will concentrate only on my impressions of the user experience during the very first 10 minutes after you get home with your brand new iPOD still in the box and a wallet that feels $400 + TAX lighter...

Let’s get started. You already went to your favorite electronic store straight to the dedicated Apple section. You asked for Video iPOD... the teenager you asked to opens the glass cabinet that stores 3 or 4 iPODs and hands you the box thinking "you bastard! I want one of these for myself!". After checking out all the accessories (and perhaps picking up some) you went to pay for it, felt guilty for spending so much money on an luxury electronic toy, jumped in the car, ran home....

...you are finally sitting at your desk, turn on your computer and look at the brand new shiny box staring at you and begging to be opened. Here is what you are going to think:

The product comes in a very small and slick package. If you are like me the thought that you paid too much for such a small box will cross your mind. Don't worry, that thought won't last long.

The package contains the iPOD, CD with iTunes + iPOD drivers, a bag with various things including the earpieces and the USB connector and a very tiny manual. The manual may seem too small to be useful, but amazingly you don't need anything more than that. I didn't even look mine. iPOD is truly easy to use. Good job Apple!

The package is well done, however you need to be careful because the device itself is not secured in any way to it. When you open it up it will fall off the package on your table (or floor) if you don't keep the box horizontal. With the $400 still in your mind that won’t be a pleasant surprise. Apple should either secure it a bit better or change the design of the package to avoid the problem.

The parts with wires (USB and earpieces) are inside a sealed opaque white package. Such package can be hard to open. You would be tempted to open it with scissor with the risk of cutting the thin wires inside. A transparent bag, or a bag with an easy to open mechanism, would have been a better choice.

The ear piece foam covers are very thin and over packaged. To take them out the package you are supposed to rip the package along an especially made cut. If you do too quickly (still shacking for having dropped your iPOD on the floor) you would rip the ear piece too. You need to use you scissors or you need to be extremely careful. Apple should review the choice of packaging here. A small transparent plastic box that you can use to store these delicate parts would seem like a much higher quality choice.

Even if you succeed in taking the foam covers from the bag without destroying them you’ll eventually find that they are useless; too thin and flimsy. They come off the earpiece way too easily; they cover the “L” and “R” labels on the ear piece and they are just annoying.

I guess I have small ears because the ear pieces don't fit in mine; they fall right off. To solve the problem I had to buy a third party attachment (made by Griffin) that allows me to select a smaller dimension. I recommend such attachments if you have the same problem. Given that I'm the only person I know that seem to have this problem I believe that Apple has no reason to worry much about it.

The pouch that comes with your iPOD is cheap and doesn't have any pocket for the ear pieces. Not big deal but for the price they could have done a bit better.

In order to install iTunes you are asked to type-in the serial number of the iPOD. That 11 characters alphanumeric code is printed in the back of the iPOD and is WAY too small. I mean, tiny! If you have any eye sight problems you'd never be able to read it. You may need a magnifying glass, no kidding! I don't have any eye sight issues and I struggled. Apple, can you please print that darn code a little bit bigger? Please? It’s not going to cost much, I promise!

If you use Windows you need to reboot your machine after installing iTunes. Oh well. I am used to it… but still annoying. I bet this is Microsoft fault, and not really Apple.

iTunes really wants to get a credit card number from you, even if you just want to download something free from the music store! Why do they want to get that number from me? I don't like that at all. Apple, if you have free stuff and that’s all I care about, can you please not ask me my CC number? Thanks!

If you download something free Apple will send you an email that looks like the confirmation of an order with balance $0. I personally don’t like that. Every time I get such email in my inbox it makes me think somebody used my account to buy music in my name using my CC.

Overall the iPOD is an awesome device but still find that lack of attention to the details of the user experience in the first 10 minutes of the purchase is something that requires very little for Apple to fix and that could make an OK customer experience into an almost perfect customer experience.

UIEvolution's UJML 2.0 !! Technology for everybody to play with!

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 10:59:30 PDT

UIEvolution released a beta of UJML Platform 2.0, the new and improved version of the powerful UJML platform. The best thing is that it's free! You can download it and use it as much as you like!! [for non-commerical purposes]

This is an exciting technology milestone that should please anybody that ever tried to develope and deploy truly cross-platform software targeting any device and any network. Cellular phones, PDA, PCs... you name it.

To give you an idea of what you can do with UJML 2.0 I'll mention that this is the new and improved version of the technology used to develope some of the most exciting titles for mobile available today. Some examples of products developed entirely in UJML are: The Chronicles of Narnia for Mobile, Narnia Chess, Trivial Pursuit, ESPN Bottomline, mobile movies.com, Square Enix Excite Fusion, Square Enix Gallery and many others.

Check this out for more screen shots and details.

Also, check my post about the fire simulation algorithm to see an example of UJML written by me in action.

What does Platform 2.0 offers compared to 1.5? There is a long list of features and I reccomend that you download the SDK and try it out. The documentation is pretty good.

My personal favorite 3 additions to this version of the platform:

A completly new IDE with integrated editor and debugger based on the Eclipse platform is the most obvious and noticable change. This makes development alot easier compared to 1.5!! You are also going to love the automatic update feature that will bring to you all the latest and greates additions and fixes.
The major addition in the UJML 2.0 language is the new object model based on the concept of components.
Another important addition to the language is the concept of resizable arrays

Enjoy!

When (beta) web sites crash...

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 11:00:03 PDT

I see many of the major web 2.0 beta sites down more and more often lately. Here is an example of a screen shot of what you can expect at times. Click on it to see it in full size.

My son is a comedian.

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 11:00:22 PDT

My son Marco is about 3 years old and he can be as funny as a professional comedian. Sometimes he means to be funny; sometimes he just is naturally. I don't know where he got that side, but he just cracks me up at times. Today just before dinner he looked at me all serious and proclaimed:

I WANT CHICKEN LITTLE SOUP!

LOL. I almost died. When I recomposed myself I realized that he meant "chicken noodle soup".

I don't know why but the image of a chicken little soup was just hilarious. I had to share it with you.

Ah... I almost forgot... since I'm in the "chicken" and "funny" topic, check out this crazy link: http://www.subservientchicken.com/

The invasion of the beta sites

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 11:00:55 PDT

BETA. It used to be just a Greek letter or a code name for programmers and geeks; today is a corporate status-symbol and is recognized by most people.

Every website and web-service seems to be released in beta in the Web 2.0 world; that is not such a bad thing, except that the beta status sometimes lingers for years. I decided to call this "the invasion of the beta-sites".

The little "BETA" icon is popping up everywhere next to brand names and company logos. The combination of the old "TM" (Trademark) and the new "BETA" is now a must-have around catchy and colorful free-service names ending in .COM.

Perhaps this period will be remembered as the era of the .BETACOMs that followed the crash of the .COMs (.ALPHACOMs?).

[Gosh, I love playing with words.]

I decided to start documenting this moment in time and create a little collection of the BETA-LOGOS. I'll add new logos to this collection and republish this post as I go. Please suggest new ones if you know of some that I missed. Subscribe to my RSS feed to get the latest updates.

You'll notice how many of these logos are from Google, which I believe started this beta-site-trend. More and more sites are opening everyday and following the Google example.

NOTE: All the images in this page are owned and trademarked by the respective owners; I publish them here only for historical documentation and as a necessary veichle for commentary and criticism that is the subject of this post.

Web 2.0 Microsoft style: infiltrate and conquer!

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 11:01:19 PDT

Looks like Microsoft is investing even more into a business model Web 2.0 style with a twist.

See: http://officelive.microsoft.com/

Some of the main Web 2.0 elements are all there:

(1) On-line service free for the subscriber.
(2) Subscribers are the content providers.
(3) Service released early as Beta.
(4) Advertisement supported model.

Sounds familiar?

Obviously they also have to inject their Microsoft twist to it; a perfect trojan horse methodology: infiltrate and conquer...

If you try to subscribe using FireFox they tell you to go get IE.

Again, sounds familiar?

March 8th, "Festa della Donna"

lpasqualis@gmail.com (__LP__) — Mon, 26 Apr 2010 11:01:48 PDT

March 8th in Italy is "Festa della Donna" or "Women's day". On this day men in Italy traditionally bring some "Mimosa" to all the women they think they will meet during the day. “Mimosa" is a small yellow flower that grows on Mimosa trees and that blooms right around the beginning of March. It is not uncommon on March 8th to see guys with large boxes full of Mimosa going to work or to school in the morning, ready to distribute the yellow flowers in large quantities. Many people even grow Mimosa trees in their back yard to make sure they have enough flowers on March 8th. I thought many times to bring this tradition to the States and on March 8th go around and give Mimosas; I wonder if that would seem weird. I bet it would; I also bet I woudn't be able to find Mimosas very easily around here. Oh well :) I'll just post a photo for all the women that I know. Happy woman's day!!