There will be more stuff in the coming weeks. I hope some of you will follow along… It won’t all be as geeky as this post… well.. pretty geeky, but not quite this geeky.

And here is how I ended up:

To help with scale… the first picture is my old 15″ Mac Book Pro and a 19″ CRT. The second picture is my new 17″ Mac Book Pro and a 24″ LCD.

The entire setup is sitting on a standard cheapo corner desk from Staples.

The laptop is on a Plexiglas shelf. The LCD is mounted on the copper stand, not the wall. The keyboard and mouse stand is not attached to the laptop/monitor stand.

The laptop is very accessible so it’s quick and easy for me to yank it off the stand and go to the office or back to the couch for a movie.

The whiteboard I affixed to the tilted area in front of the keyboard has come in extremely handy a number of times.

I had planned on doing a detailed write up on how I built this thing…. but, it’s been a month now and the mojo is gone. I’ll just bust out some “highlights”… I’m happy to answer any questions you have.

I built the structure entirely out of copper pipe and rivets and I made the shelves from Plexiglas. It took me about 30ish hours to complete… Much of that time was spent experimenting and wasting materials.

The monitor is about 2-3 inches higher than my initial design (the top of the laptop and LCD should be flush) because I ordered the wrong mount and was too impatient to wait for a new one… so I “fabricated” an “adapter” out of some random junk… and two Isaac Asimov novels… really. I’ll get around to fixing that.

You may not have noticed the mood lighting… I added a small lamp behind the whiteboard which gives me decent light at night without having the overheads on.

Here’s a shot from during construction:

I stuck with stock plumbing parts from Home Depot… Which means I basically have elbows, t-joints and straight bits to work with… this led to lots of joints and some interesting angles for stability.

The End.

I am also switching off roller, and on to wordpress for this blog… wordpress is much more feature rich than roller. Hopefully it will inspire me to blog more than once a quarter.

In other news… you should check out the clark island boat works blog, my friend Mac does the boat and blog building and it’s pretty interesting to see what goes into one of these boats…. even if you don’t really care about boats. At least give him a click or two.. he watches the damn traffic stats like some kind of junkie.

class InflationService {
    boolean transactional = true

    // this is where the live CPI data lives
    String cpiURL = 'ftp://ftp.bls.gov/pub/special.requests/cpi/cpiai.txt'

    // map of year to CPI average String -> double
    def cpiMap = [:]

    // track the last time we updated from the source data,
    // for long lived apps we don't want to get stale.
    long lastLoadTime = 0;

    // always use the current year as the target year
    double calculateCurrentDollars(String fromYear, double value) {
        refreshCPIData(false)

        GregorianCalendar date = new GregorianCalendar()
        def year = date.get(Calendar.YEAR)

        // not sure what the CPI table looks like in january...
        // this should account for no record for the current year...
        // more that 1 missing year is a serious problem
        def toYear = String.valueOf((cpiMap[String.valueOf(year)] != null) ? year : year-1)

        return calculateYearDollars(fromYear, toYear, value)
    }

    double calculateYearDollars(String fromYear, String toYear, double value) {
        refreshCPIData(false)

        def toCPI = cpiMap[toYear]
        def fromCPI = cpiMap[fromYear]
        // here's the actual math...
        // pretty simple when you final get down to it          // TODO - check for nulls or zeros and throw exception.
        return value * (1.0 + ((toCPI - fromCPI) / fromCPI))
    }

    // refresh cpiMap if last update was more than 1 day ago
    // OR forceUpdateNow param is true.
    public void refreshCPIData(boolean forceUpdateNow) {
        long oneDay = (1000 * 60 * 60 * 24)
        // update once per day. (or if forced)
        if (forceUpdateNow || (lastLoadTime + oneDay) < System.currentTimeMillis()) {
            lastLoadTime = System.currentTimeMillis()

            // grab the "tabular" data right from The Man
            cpiURL.toURL().text.eachLine {yearLine ->
                // find all the lines that start with a year..
                // these are the useful bits of the doc
                if (yearLine.matches(/^\s+\d\d\d\d\s.*/)) {
                    // split the line up into individual values
                    def yearList = yearLine.split(/\s+/).findAll {it.size() > 0}
                    // the first item is the year.. hang onto that
                    def year = yearList[0]
                    // the rest of the values are CPI values for each month
                    // (some averages at the end that we ignore)
                    yearList = yearList.tail().collect {Double.valueOf(it)}
                    // average all 12 months for every year...
                    // except the current year could have less than 12 months
                    int idx = yearList.size() < 12 ? yearList.size() - 1 : 11;
                    cpiMap[year] = yearList[0..idx].sum() / (idx + 1)
                }
            }
        }
    }
}

here is a simple test.

class InflationServiceTests extends GroovyTestCase {
    InflationService inflationService;

    void test2007to1990Dollars() {
        assertEquals('got wrong answer', 63.01572800870056,inflationService.calculateYearDollars('2007', '1990', 100.0));
    }
}

It shouldn't matter which direction you want to do the conversion in.. 1990 dollars to 2007 dollars or 2007 dollars to 1990 dollars. The data starts in 1913 (the year the federal reserve was created) and runs about a month behind.. so I write this in September 2008 and the CPI is available through August 2008.

I wish I had time to dig into the Roller source code.

All in all, I like it.. it's a cool system that's relatively easy to maintain and I have full control.

I've been working on this theme a little..

I added a tag cloud on the right and a list of old posts. I'll try to tag each post pretty well so that maintains good utility.

Each post now has a few social bookmarking links under it. You most likely know what they are, and if you don't, they probably won't make your life any better. Leave a comment if there's some service you really like.

I have also added a widget from my RSS reader. I'm subscribed to dozens of RSS feeds from a pretty wide variety of topics. Any I flag as “shared” will appear in that box on the right. I don't flag very many… but I think they're usually pretty good

I just found out about TED fairly recently, and I’ve been watching the videos voraciously ever since. If you’re not familiar with TED it’s a yearly conference where some of the worlds most innovative and intelligent people give talks from 5 to 40 minutes in length. It’s been going on for 20+ years, and has featured household names in science, politics, entertainment and just about any field you can think of. Most amazing are the people who most of us have never heard of, like Johnny Lee, with some incredible new invention, idea, insight or even just a great story.

Here are some good ones

• Alan Russell on regenerative medicine
• Hans Rosling shows some amazing graphical visualizations of global historic data
• Larry Brilliant eradicating the last case of Small Pox, personally

I could go on.. there are very few that I would say are not worth seeing, and there are hundreds out there, with more published all the time. The full podcast feed is here.