Saturday, April 19, 2014

Rotator Cuff Update





I had surgery on my left shoulder back in January. I thought I'd post an update in the hope that it might help some other middle aged person who's facing a similar situation.

I hinted at the problem in my 2013 retrospective. I did my best to manage it as a chronic condition. I even went back to swimming, albeit at a greatly reduced effort, frequency, and intensity. But by the time my surgery date approached, I noticed that the muscles behind my left scapula felt markedly worse. I was grateful to be on the surgical calendar.

It was the first time I've ever been under the knife. I tried to remain calm, but when they took my heart rate and blood pressure on arrival at the surgery center both were sky high. The anesthesiologist put some valium in the solution when they prepared me for the nerve block "to take the edge off". I found out later that I had fibrillation again when they intubated me. They were worried enough to send me to a cardiologist for an echo cardiogram after I returned home. All was well. It was fear!

I was wheeled into surgery at 11:15 am. I believe it was 3:30 pm when I woke up in the recovery area. They found out that I had a bone spur on my collarbone that was abrading my labrum. Some time with power tools took care of everything. The nerve block worked wonders for 36 hours - I had no pain at all. I took the pain medication to stay ahead of it, but I hate taking pills. I weaned myself down to one at a time, then off completely after a few days. I never experienced any pain at all.

I was in physical therapy the day after surgery. The exercises were little more than moving and stretching, but they were key for avoiding excessive scar tissue buildup and stiffness. I went to physical therapy faithfully three times a week and did the exercises on my own at home. At first they were difficult and frustrating. One of the worst was the 1 kg medicine ball. I had to put it on a spot on the wall at shoulder height, then rotate the ball about that point ten times in each direction, three times each. Those small muscles in my shoulder needed to control the ball simply weren't firing. I could barely keep the ball on the spot, and just a few reps left my shoulder exhausted. But I stayed with it, going so far as to order a ball of my own so I could do those exercises at home along with the hand weights.

The physical therapist was terrific. He said there's a controversy in the field over when to start physical therapy. If the surgeon lacks confidence in his repair s/he's likely to recommend remaining in a sling and immobile for up to five weeks. The typical repair technique calls for drilling two holes in shoulder bone and inserting pins to hold the stitch and muscle to the bone. Pulling the pins out is catastrophic. My surgeon drilled all the way through the bone and looped the stitch through the holes. The only way to pull it out is to destroy the shoulder. The more reliable attachment, combined with arthroscopic minimally invasive cuts, made it possible to start on therapy right away.

The therapy room was always filled. Old and young: the former because of long use and the latter from sports injuries. One afternoon I was doing my exercises next to a man my age who was struggling with a range of motion exercise that I'd endured eight weeks earlier. "What are you here for?" I asked. He'd had his elbow repaired. When I told him I'd had my rotator cuff fixed, he said "I had that done last year by another surgeon. I was in a sling for five weeks; I couldn't drive for five weeks; I slept in a recliner for five weeks. I started physical therapy after discarding the sling and endured it for six months, and it's still not right. You look like you're doing pretty well." His eyes popped out of his head when I told him I'd had my procedure just eight weeks ago.

I was in a sling for ten days. I was driving once I left it behind. I started on physical therapy the day after. Seven weeks after surgery did my first lengths in a pool. I was discharged after eleven weeks and feel almost 100%. I'm still doing the exercises on my own at home once or twice a day. I'm working my way back to regular swimming, including Masters. I'm back out on the road running and feeling good.

So if you're reading this and considering a procedure, take heart. It's possible to come back. I'm on my way.

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Saturday, April 12, 2014

Heartbleed and Passphrase






The news has been filled with stories about Heartbleed, a flaw in OpenSSL that puts web sites and information at risk. We're told to change passwords immediately.

What a pain! I've got usernames and passwords all over the web. Changing all of them, keeping track, and remembering later will be incredibly difficult. The Internet has a password problem. I can't wait until I have my own quantum cryptographic key generator so I don't have to remember.

So what to do? I came across a nice site called Diceware that spells out a recipe for generating pass phrases. I have a backgammon board in the house, which means that I have four dice handy at all times. But a fifth? I can't use the doubling cube very easily, can I? The idea of manually rolling dice to generate a key, going to the wordlist to look up a word, and recording that pass phrase for a given site seems like too much work, too many steps. So low tech!

Being a computer programmer, I'd rather spend a day coding a solution to a problem that would take five minutes to do by hand. So that's what I started working on last night. I finished it today and uploaded the result to a Github repository. It includes the source code for two Java classes: Die (a six-sided die that uses a random number generator to produce rolls) and PassphraseGenerator (a command line app that generates a random pass phrase using the Diceware recipe), the Diceware word list, and an executable JAR that makes execution in a command shell easy.

This exercise recalled the wonderful xkcd comic about password strength. I always loved the entropy calculation that gave a measure of password strength, so I incorporated the calculations into my application. I also gave a way to calculate the entropy of a given pass phrase using command line arguments. The first argument is the pass phrase, surrounded by double quotes if it contains spaces, and the second is the alphabet size used to generate the pass phrase. I've been using simple pass phrases on my work computer for years now. I put the one that I currently use in to see what its entropy was. It has 42 bits of entropy. At 1000 guesses per second, it would take 241 years to crack if my calculations are correct.

It was a fun and fruitful exercise. It made me happy, like my Mandelbrot solution from a few years back. I need to do more of that.

The last remaining problem is that most sites have ridiculous rules for passwords (e.g. "between 8 and 15 characters; must include one capital, one number, one special character") that actually make them weaker and harder to remember. I'd much rather generate some four word pass phrases and use those!

I'm struggling with software development lately. I'm trying to swallow a lot of new techniques. It makes me happy when I can solve a small problem like this once and for all. Uploading it to Github lends an air of permanence that I love: "Don't have to think about that problem anymore!"

Maybe that's the answer to all hard software problems: Decompose the big problems into lots of small ones that you can solve and upload to Github. Solve and forget that problem, make yourself happy, and move on to the next.


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Tuesday, December 31, 2013

Another Year Looking Back






Goodness, has another year gone by already? I've written a couple of these retrospectives, including last year's effort. I was feeling pretty good after finishing my first half marathon. I had logged 313 miles on roads and trails, the best running total I've ever had. I swam 243,000 yards - subpar compared to my average 346,000 per year, but I was happy about learning how to run again. I had every intention of running another half marathon in 2013 and perhaps trying my hand at a full marathon. I had my training plans all set. I signed up for a half in Simsbury in June and planned to re-enter the Hartford Marathon again in October.

Unfortunately, I hit a couple of snags.

I was swimming an IM set during the second week of January when my left shoulder started hurting me. I'm not sure, but I think I was splitting a lane with another swimmer. I remember ticking the lane marker with my left hand when my left arm recovered over the water. Is that when it happened? I tried again the next day and found that it was still sore. I stopped swimming butterfly for 4-6 weeks before trying it again in Mar. I couldn't even complete a length: my shoulder was hurt. I went to see my general practitioner about it. When I told him I did it swimming butterfly he said "Are you crazy? A guy your age shouldn't be swimming that stroke!" He suggested that I had a partial tear in my rotator cuff. He said he could spare me a bunch of co-pays at the physical therapist by recommending rubber band exercises to build up my shoulder.

I was doing fine until I went out into the yard in April to clear some brush. I started experiencing pain in my neck and numbness in my left thumb. I've had cervical spine issues before: C6-C7 disk bulging caused incessant pain in my right shoulder, down to my elbow. This time the symptoms suggested C5-C6 disk problems. I resigned myself to a visit with an orthopedic surgeon. An MRI confirmed the initial diagnosis. It's not uncommon. It's likely that a random sampling of men my age would turn up several torn rotator cuffs.

I've never had surgery before. I wanted to do all I could to avoid it this time, too. I went to physical therapy with the goal of managing it as a chronic condition. I gave them a tough task: they had to sort out my neck issues before tackling my shoulder, but I made enough progress to make it back into the pool in August. I decided that I wanted a second opinion, so off I went to another surgeon and physical therapy team. I heard something there that changed my view. The surgeon was an accomplished swimmer (far better than me) who understood my love of the water. At the first session the physical therapist said "If I had a condition that I knew could be sorted out, I'd want to take care of it." That flipped the switch for me. I did all the exercises and planned to add my name to the surgical calendar in 2014.

So my totals weren't so impressive this year: 220 miles running, none longer than 8 miles; 131,000 yards swimming, my worst total by far since I started keeping track in 1996. I'd like to improve on both next year. It'll start by getting my shoulder sorted out. If it's a simple cleanup operation, I'll be immobile for a week or less. I'll be able to start on regaining full range of motion right away. If things are unstable, and stitches are required to make the shoulder stable again, I will be immobile for a longer period and the therapy will be more difficult. I'm optimistic for a good result. I feel good in the water now. I don't do butterfly anymore, but I can still do a modified version using the dolphin kick and alternating each arm. I don't know if I'll ever have that wonderful feeling again where I'm flying over the water. We'll see!

One goal for the year was to dive into on-line courses and deepen my knowledge of statistics. I hit a home run there. I completed an intro statistics course at Udacity early in the year. I wanted to learn something and see if online courses suited me, so I didn't commit to a certificate. The next three courses at Coursera.org were a great success. I earned two certificates with distinction and have hopes of meriting a third. I loved the courses and learned a ton. I plan to add more in 2014.

I had a great year reading, both technical and non-technical. It's not often that you can say you've discovered a favorite poet, but I did this year. Read Billy Collins' Aristole for one reason why.

I signed up for Twitter. I'm not sure that's a positive. It's a time sink, one that I cannot afford. I've spent too much time reading stuff that makes me laugh, think, and fume. I micro-blog and argue with trolls far more than I should. I rise to the bait easily. This is one habit that I hope I won't embellish in 2014.

I'm grateful to still be working. It's a year-to-year thing nowadays. We're all temporary employees, all at the pleasure of our employers. The world seems less stable than it was when I was younger.

I'm still married to the same wonderful woman. We're outliers by a long way.

My children are both out on their own, laying the foundations for their adult lives. They're still within a car and train ride, which is a great thing. I love seeing them.

My mother is still with us and doing well.

I still have plenty of technical goals. I need to write more applications and dive deeper into data analysis. Bayesian analysis and multi-chain Monte Carlo are at the top of my book pile this year.

I'm glad to still have that sense of optimism and anticipation at the turn of the calendar.

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Monday, December 23, 2013

Favorite Poet





I love to read, but poetry has never been my favorite. I've dipped my toe in the water, but I've never dived in with gusto.

I had a great AP English teacher in high school who fanned the embers of my love of reading into a roaring blaze. He seemed to have read everything. Whenever he'd recommend something I'd run to the library and devour it. More often than not he was right. Why else would I have read the Studs Lonigan trilogy? (Go get it - it's great.)

But he couldn't duplicate the trick for poetry. He taught us about different meters. I remember iambic pentameter and Robert Frost snippets, but little else. I confuse the names with guitar scales: "Did Shakespeare use mixolydian, or was that Stevie Ray Vaughn?"

My indifference to poetry persisted until one Saturday morning when I was out and about with the dog, listening to "Wait Wait, Don't Tell Me!" on NPR. The guest was Billy Collins. He was so entertaining to listen to that I resolved to give his stuff a try. My local library had a copy of his "Sailing Alone Around The Room". It's the best poetry I've ever read: beautiful, not dry or boring, modern and fresh. I can't stop reading the guy. I take a few in every day, re-reading the ones that I like. I've read them aloud to my wife, because they demand to be given voice the way great songs have to be sung. Poems that I like! I'm astonished at the thought.

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Wednesday, December 18, 2013

Best Coursera Yet




I finished my third Coursera course tonight: Data Analysis, eight weeks of learning R and its application to statistics problems. I've enjoyed all three, but this one topped them all. It was a difficult eight weeks. I spent a lot of hours at night after work and weekend time poring over assignments. It's been tiring but worth it. I've remembered the statistics I'd forgotten, learned a lot of new things like generalized linear models, and deepened my knowledge of R. It's exactly what I set out to accomplish when I started taking on-line classes a year ago at this time. I wanted to see if I could adapt to a new style of learning and self-education. I wanted to prove that I could still absorb challenging material. I'm at an age when it's easy to sit back and tell yourself that you already know it all, that you're too old a dog to learn new tricks. Did I still have it in me? I think I succeeded on all counts.

The professor was Jeff Leek, who's on the faculty of the Johns Hopkins biostatistics department. They claim to be pre-eminent in the world, and after sitting through this course I believe them. His graduate students are fortunate.

I've earned certificates with distinction for the two other classes I've taken. I calculated my point totals for quizzes and assignments for 'Data Analysis'. I think I squeezed out another distinguished certificate. I'll have to wait a week or two to see if my numbers match those from Coursera, but I'm confident that it'll turn out well.

I've got a lot of other tasks lined up. I want to take more of these classes next year, but I'm uncertain about what to take. I want to go further with R and statistics, but there's no clear choice listed in the catalog. I might start haunting Kaggle.com and applying these new skills to problems. I've got some development tasks to get back to.

I found out that I'm two speeches away from achieving the Toastmasters Advanced Leadership Bronze designation. I'll fulfill those easily in the next few weeks. That would be three awards in one fiscal year. I'll only have ten speeches to achieve Advanced Communicator Gold and the Advanced Leadership Silver to become a Distinguished Toastmaster. Who would have thought it'd culminate in this when I started in 2008? Maybe I can do it by mid 2015.

I plan to relax a bit over the holidays. It's been a nice way to end the year.


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Sunday, November 10, 2013

More Progress







I received the certificate with distinction for Coursera Data Analysis Using R tonight. I know it shouldn't matter, but it does to me. I want to hold myself accountable and keep pressing with these courses.

Data Analysis has completed its second week. I'm in the midst of the first data analysis assignment. I have more work to do on it, but I think it's going well. I have a plan of attack that I'm following. I think the writeup portion plays to my strength. I'm slowly becoming more comfortable with R. I need to be reading more statistics books to figure out how to attack problems better.

Toastmasters is moving along, too. I finally completed the Competent Leader designation. I also finished the requirements for Advanced Communicator Silver designation. Just Gold to go, then two more leadership tracks to become a Distinguished Toastmaster. I don't know if I'll manage the leadership portion, but the speaking track is well within reach.

But wait - there's more.

I still have to master user interfaces with HTML5, CSS3, JavaScript, and jQuery.

And now there's vert.x, the non-blocking IO framework for Java.

So much to learn, so little time.

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Tuesday, October 22, 2013

Another One Bites The Dust






I just finished my second Coursera course. It's hard to believe that "Data Analysis Using R" started just four weeks ago.

This wasn't a terribly difficult course, but lecture time added up. The assignments weren't hard conceptually, but I found myself struggling with the API and the docs. "How do I do that?" was a common question. It was easy to think how I'd do something in a language that I knew better, like Java or Python, but I wasn't always able to conjure up the R equivalent at will. I had to do small experiments on the fly to figure out how to make the language do my bidding.

The third programming assignment set was time-consuming. I was behind the eight ball because I was out of town at a family wedding the weekend before it was due. Thankfully we were given an allotment of late days that we could apply as needed. I used up three of them after returning from MN so I could get the assignment in late without penalty.

Debugging in the R environment is crude, reminiscent of the gbd command line debugger that comes with Java. It's a comedown for a person who's used to using the best IDEs in the world to work with Java and Python. I started using the R plugin for IntelliJ for the fourth assignment. I hope they keep expanding and improving it.

R does have some rudimentary object-oriented features, but it's firmly in the functional camp. A friend pointed out that R looks similar to JavaScript. As usual, he's right. I started eschewing the '<-' assignment notation in favor of '=' to make the visual resemblance stronger. The Renjin interpreter makes it possible to run R inside Java. I found out that you can also run R on CUDA. I'm looking forward to trying those packages and seeing what performance benchmarks would look like.

This one was a sprint. The next one, "Data Analysis", will emphasize problems that R is used for, diving deeper into regression and analysis. I'm looking forward to getting back in touch with my mathematics roots. It begins next Monday.


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