A few days ago a new (to me) book arrived, Dead Reckoning by Ron Doerfler. The book is yet to be read (other than a quick scan), but the title reminded me of the method of navigation by the same name.

Dead Reckoning navigation is the art of estimating one’s position based on the last known position, elapsed time and velocity (or estimated distance) and heading. In other words, given a known position and an estimate of bearing and distance, the current position coordinates can be estimated (or calculated).

In the context of the book, Dead Reckoning refers to methods of calculation (or estimation) of mathematical problems without the use of calculating tools other than one’s brain. It is going to be a fine read and something that will add to my personal toolkit.

But the term reminded me of my wanderings a couple of years ago. As I traveled around the country, I had only a general idea of where I was going. Given that there was no specific destination and no specific schedule, I would stop along the way, retrieve my ancient glovebox atlas, and estimate my location on the very small maps. Using that information I would set a course and make a decision about where I might stay for a night or a few days.

Once near that location, I would open Google maps on my iPhone and look for a place to stay. After identifying a few possible candidates, the reviews would inform whether the place was acceptable. I would then either just drive in or phone ahead for a reservation.

I thought of this as an automotive form of dead reckoning. Given I had no specific destination, I had little need for the precision of GPS and the inherent maps. I just needed a general direction and an estimate of distance so I could decide where to stay for a night or a week.

I was also reminded of how we navigated when I was a young man. There was no GPS system. There were paper maps of various scales. I loved those maps and still have quite a few of them. I would plan a trip with a map and a notepad and I was able to estimate travel times and ETAs without a lot of effort. Sometimes navigation needed a telephone call (from a pay phone) to get to the destination. Often there were signs that provided directions once one was sufficiently close to the target.

There is something deeply satisfying about just using a simple map and about not having a specific itinerary to deal with. There is something satisfying about just going and then being there in that place for a bit.

I think this experience is coming for me again. There is a need in me to just wander for a bit and enjoy the journey. With journal, pen, and camera I can be very happy enjoying the world I live in.

# The Hunt

This photograph was posted to my “Instagram account, but is worth a revisit.

I see this heron many times when walking the Carson River. He is always a welcome sight, the beauty and majesty of this bird are significant. But catching a photograph of him is difficult.

Earlier this year my Fujinon 100-400mm lens arrived. This lens is a beast, literally and figuratively. It is one of the heaviest lenses I own. It is also one of the best lenses I own.

I carry it often when walking along the river. It has the ability to bring me photographs I cannot capture without it. It is not a general purpose lens, but one very well suited for wildlife photography. I love to capture wildlife with the camera. Results like this one make the expense and effort worthwhile.

# Key|Smart

A couple-three years ago I carried my keys on a ring a-jumble in my left front pocket. They were on the opposite side from my front-pocket wallet. They were forever bouncing around the bottom of the pocket and I cannot recall the number of times they poked my leg, sometimes painfully.

They also subjected my pocket to a lot of wear. I have had more than one pair of jeans lose the pocket to my keys and need repair.

About that time I became aware of the EDC “thing” and the community that grew up around it. I did not that Every-Day-Carry was a “thing” — but it is quite a thing. Keys and wallets are two significant components of EDC, along with knives and other tools. I could write several articles about this and I might.

In any event, I came across the Key|Smart. It is a small device designed to hold several keys in a compact, secure holder that is easily clipped to a lanyard or other retaining device. I bought one and it was delivered a few days after my purchase.

I read a few horror stories about users who had their Key|Smart loosen and floor sort all of their keys, some of them lost. These were individuals who carried their keys outside the pocket. If the device loosened, then there could be a loss of keys. However, for the life of me, I cannot understand why one would not hear them drop to the ground.

So I assembled the set of carry-keys (I have another non-carry keyring that holds the remainder), organized them in a fashion I thought would be optimal, and started carrying them in my KeySmart.

After a few days, I build a lanyard from some paracord that permits my keys to ride in my left-front pocket but they hang from my belt and do not lie on the bottom of my pocket. This works for me. I use an S-biner to clip to the lanyard (a loop-lanyard) so I can one-handed release the upper portion of the S-biner, retrieve my keys, and flip open the housekey without needing both hands.

This works for me.

I have reorganized the keys as the number of keys changes with time. I also have the most-used keys away from the clip end of the KeySmart.

Yesterday, I removed an unused key (probably an old Post Office key) and rearranged the spacers to put one between each key. This means the keys no longer ride against each other and they are a little easier to roll out with one hand.

Besides not having a jumble of keys rattling around in the bottom of my left front pocket, the Key|Smart is nearly silent. I rarely hear it unless it bounces against the Bestech Kendo that I currently carry clipped to my left front pocket. The silence is a boon.

I can readily recommend this handily little device.

# Dynamic Range

One of my favorite YouTubers is Steve Guttenberg. He does a daily show that covers sound equipment and his experience in the high-end audio industry. He sometimes/often includes a music review. I don’t always like his choices, but I have found some music that I really like by listening to his recommendations.

In a recent daily show, Steve mentions a Frank Sinatra recording, The Concert Sinatra. After watching Steve’s show, I searched Spotify for the recording and found it.

As I write this, I have the music playing as well. I am struck by the dynamic range of the recording. What I mean by that is the range between the softest and loudest passages of each song.

The dynamic range is huge! It is so musical and such a contrast to so many recordings of popular music. In his daily show, Steve mentions Beyoncé and a recording she produced that he liked. (But that recording was not sufficiently memorable that he recalled the name of the album.) He contrasts the liner notes from the Beyoncé and Sinatra recordings. In the latter are details about the recording process, the musicians, and the studio. In the former… nothing.

As an aside, one of the reasons I like classical music is the dynamic range in the recordings. A big part of the presentation is the range in volume that the music is played. There are markings on the score to indicate the composer’s intent (for loudness). Dynamic compression of classical recordings is either not done or is limited. This gives classical music a completely different sound than most popular music. (There are exceptions, of course.)

I am not knocking Beyoncé. She is a talented and successful entertainer. There is nothing wrong with her musicianship. But her focus on not on being a musician, but an entertainer. Sinatra was an entertainer, but I think he was principally a musician. It shows in this particular recording.

I do not have any Sinatra in my collection. That is a lack and something I am going to rectify. I think a good beginning will be The Concert Sinatra. It is a beautiful recording of some classic songs. I am going to bet it will be dynamite on headphones.

# Linear Interpolation

Back in the old days, we used tabulated values to compute values of transcendental functions so that the results could be used in subsequent computations. We had tables for logarithms, trigonometric functions, and the like. There was no calculator or computer with which to enter a value and press log10 to estimate the logarithm of the number.

The method I was taught in high school (I think, it was a long time ago) is called linear interpolation. The assumption is that a straight line between entries in the table is a reasonable approximation for values in between.

That is not strictly true, because all of those functions are actually curves and deviate from a straight line between any two points on the function (according to the graph of the function). But, use of interpolation is certainly sufficient for scientific and engineering calculations.

Therefore, I learned to use linear interpolation to estimate the in-between values. The process is simple, computationally. The bounding values from the table are used to estimate a slope of the line between the two values. That slope multiplied by the fraction of the distance between the interval endpoints of the desired value of the independent variable is added to the initial interval endpoint of the dependent variable. The result is the estimate of the dependent variable on the bounding interval.

Probably 20-years ago I was working on a spreadsheet to route a runoff hydrograph through a reservoir. The algorithm is called modified Puls and is an expression of the conservation of mass principle of the hydrograph through the reservoir with the assumption that the slope on the reservoir surface is zero (it’s flat). The process involves generation of several tables of values and then using those tables to execute the algorithm. Most of the time the desired values from the algorithm fall between tabulated values. Therefore, interpolation is required.

The brute force technique would be to hand code each cell of the spreadsheet to advance the calculation. I wanted a more general (and perhaps elegant) solution so that I would not have to hand code each cell. I thought it should be possible to write a general formula using the built-in search function of the spreadsheet over the range of values in the table.

I recall working on this for a couple of days. I was a professor, so I could afford to spend the time on the problem. I constructed a solution using a function in Microsoft Excel called VLOOKUP. I am not going into the details here (I have a white paper here), but it is sufficient to say that I did the work, solved the problem, and forgot about it.

I also forgot where I put my notes on how I constructed the solution. As it turns out, I needed (or rather wanted) to use this approach to solve an engineering problem I’m working on. I couldn’t find my notes. A couple of weeks ago I hand-coded the cells just so I could get a solution. But last it became apparent that I might have to make several solutions of the problem using the same tables.

I needed to regenerate the general solution, once again. I did this a couple of days ago. Then, yesterday morning, I woke early and was unable to go back to sleep. So, I rose, made coffee, and wrote my notes so that I would have a reference should I need to use the solution again. (Hence the production of the white paper above.)

I am reminded that there are many times we work out a problem, or we learn something that challenges us in some manner. But then, with the immediate problem solved, we move on and never take time to note what the problem was, what the constraints were, what the solution was, and what we learned. We are carried away by the pressing current of other tasks, other duties, or just the ebb and flow of life.

Then, weeks, months, years, or decades later, we find ourselves facing a similar problem that, hopefully, would have a similar solution. In a frantic whirlwind of energy, we search for the solution we know we found but cannot recollect. We know we solved the problem. We remember working on it, struggling intellectually or emotionally, and the expenditure of intense energy grinding toward the solution. Then, solution found and the immediate need passed, we remember having moved on without taking the time to reflect. We curse our impatience, or failure to document what we learned, and our stupidity.

But we know, having solved the problem once before, we can find the solution (or an equivalent solution) again. So we pick up the trail, work out the solution, and solve the problem once again.

Then what? The wise will set the brake, pause, and make note of the problem, the constraints, and the derived solution. I know that I learned my lesson on this one. Will I make the same error again? Probably. But I won’t make this same error again. I have my notes. I know how to solve this problem.

What about you? What is the problem you’re faced with? Is it one you solved before? Did you pause to make notes after developing the solution? Will you make the same mistake that I did?

# Fall Colors

The Girl and I always enjoy our walks. But when the fall comes, the weather cools and our walks get even better. She does not burn out as quickly and loves all the fall scents.

I love the way the light changes as the sun falls in the sky. The quality of the light is less harsh, even during the midday hours. As the leaves change, the light is filtered not by the green of summer foliage, but by the warmer colors of the change. The yellows and reds warm up the light and the change excites my eyes. I almost always carry a camera, but I am really motivated in the fall.

Yesterday morning did not disappoint me. As we walked one of our favorite trails along the Carson River, the late-morning sunlight filtered through the gorgeous yellows of the changing cottonwoods. I was happy that I carried the Fuji X-H1 with the Fuji 18-135mm lens with me. That camera is a game-changer for me. The lens is one that has been in my kit from early in my Fuji experience. It is one of the better walk-around lenses that I have used. It certainly did not disappoint me Sunday morning. I came home with at least a handful of keepers.

I think this one is one of them. It reminds me that the time moves on, the seasons change — those outdoors as well as those inside us. The last few weeks challenged me. A project I am working on is a significant technical challenge. The struggle is reverse engineering a hydrologic system to determine how what happened came to be. The time pressure to get through the analysis is a secondary challenge and can add significantly to the pressure.

But, I think I have the system mostly figured out. A change in the schedule is taking some of the pressure off. I was blessed this weekend to have a few hours to just breathe. That breath was a most welcome relief and a reminder that the seasons change. Projects come and go, like the seasons. But there is more to life than just the work and the time outdoors this weekend was another reminder of that. I am blessed to live where I do and I am thankful.

# Monk versus Oldfield

Many years go, Pastor John would refer to Thelonious Monk in one context or another. I was not familiar with Monk and sometimes wondered who he was and what his role in music might be. I wondered if he was an aphorism, much like Dad’s reference to Barney Oldfield, who came up often when I was a young man and learning to drive.

I had not thought about either much until a few days ago (about a week, in fact). A favorite reviewer of audio equipment, the Audiophiliac, mentioned Monk in a music review. I streamed his suggestion (Thelonious Monk plays Duke Ellington) a couple of times on Spotify and was sufficiently intrigued to find a copy of the CD and purchase it.

The disc arrived today. I ripped it to ALAC (lossless Apple) and pushed it to my iPhone. I’ve been listening to it this afternoon. The material is not typical Monk (much to the chagrin of the critics of the time) but is Monk doing his thing interpreting some of the standards of the time.

The material is familiar to anyone who likes music. The recording was remastered in 1987 for this particular disc. I find it amazing that this was recorded in 1955. I was two-years-old. I’m going to enjoy this recording quite a lot. If you like jazz standards, it is worth finding a copy.