Wayne Joubert    Julia. Scala. Lua. TypeScript. Haskell. Go. Dart. Various computer languages new and old are sometimes proposed as better alternatives to mainstream languages. But compared to mainstream choices like Python, C, C and Java cf. Tiobe Index are they worth using Certainly it depends a lot on the...

John    This weekend I ran across a blog post The Rodeo Clown Theory of Personal Development. The title comes from a hypothetical example of a goal you don’t know how to achieve: becoming a rodeo clown. Let’s say you decide you want to be a rodeo clown. And let’s say you’re me and you have no The post...

John    There’s a little program called strings that searches for what appear to be strings inside binary file. I’ll refer to it as strings to distinguish the program name from the common English word strings. What does strings consider to be a string By default it is a sequence of four or more...

John    Arshad Khan left a comment on my post on the less and more utilities saying on ubuntu if I do less on a pdf file, it shows me the text contents of the pdf. Apparently this is an undocumented feature of GNU less. It works, but I don’t see anything about it in the man The post Extract text from...

John    This post ties together the previous three posts. In this post, I said that an Archimedean spiral has the polar equation r b Î n and applied this here to rolls of carpet. When n , the length of the spiral for Î running from to T is approximately bT with the The post Length of a...

John    If you know the dimensions of a carpet, what will the dimensions be when you roll it up into a cylinder If you know the dimensions of a rolled up carpet, what will the dimensions be when you unroll it This post answers both questions. Flexible carpet: solid cylinder The edge of a rolled up carpet...

John    An Archimedean spiral has the polar equation r b Î n This post will look at the case n . I may look at more general values of n in a future post. Update: See here. The case n is the simplest case, and it’s the case I needed for the client The post Approximating a spiral by rings...

John    It’s occasionally necessary to evaluate a hypergeometric function at a large negative argument. I was working on a project today that involved evaluating F a, b; c; z where z is a large negative number. The hypergeometric function F a, b; c; z is defined by a power series in z whose coefficients...

John    When I first started using Unix, I used a program called more to read files. The name makes sense because each time you press the space bar, more will show you more of your file, one screen at a time. Now everyone uses less, and more is all but forgotten. Daniel Halbert wrote more in The post...

John    I recently ran across a tweet from Allen Downey saying So much of th century statistics was just a waste of time, computing precise answers to useless questions. He’s right. I taught mathematical statistics at GSBS , several times, and each time I taught it I became more aware of how...

John    An article by Y. L. Cheung gives reasons why poker is usually played with five cards. The author gives several reasons, but here I’ll just look at one reason: pairs don’t act like you might expect if you have more than five cards. In five card poker, the more pairs the better. Better here means...

John    Yesterday I stumbled on the fact that the size of Jupiter is roughly the geometric mean between the sizes of Earth and the Sun. That’s not too surprising: in some sense i.e. on a logarithmic scale Jupiter is the middle sized object in our solar system. What I find more surprising is that a...

John    The size of Jupiter is approximately the geometric mean of the sizes of Sun and Earth. In terms of radii, The ratio on the left equals . and the ratio on the left equals . . The subscripts are the astronomical symbols for the Sun â, U , Jupiter â, U , and Earth, U F . I...

John    I was listening to the latest episode of the Space Rocket History podcast. The show includes some audio from a documentary on Pioneer that mentioned that a man would weigh pounds on Jupiter. My immediate thought was Is that all Is this man’ a pound boy The documentary was correct...

John    Are guidance documents laws No, but they can have legal significance. The people who generate regulatory guidance documents are not legislators. Legislators delegate to agencies to make rules, and agencies delegate to other organizations to make guidelines. For example , Even HHS, which has...

John    A week or two ago I wrote about Laguerre’s root finding method and made some associated images. This post gives a couple more examples. Laguerre’s method is very robust in the sense that it is likely to converge to a root, regardless of the starting point. However, it may be difficult to predict...

John    I set up a GitHub account for a new employee this morning and spent a ridiculous amount of time proving that I’m human. The captcha was to listen to three audio clips at a time and say which one contains bird sounds. This is a really clever test, because humans can tell the difference between ...

John    The famous Rule of says that to find out how many years it takes an investment to double in value, divide by the annual percentage rate. I’ll come back to that in a little bit. This morning I read a really good article, Fifty Things you can do with a Software Defined Radio. The post...

Wayne Joubert    AlphaFold, FourCastNet and CorrDiff are exciting. AI driven autonomous labs are going to be a big deal . Science codes now use AI and machine learning to make scientific discoveries on the world’s most powerful computers . It’s common practice for scientists to ask questions about the...

John    I saw someone point out recently that à Are there more examples like this What would you call the pattern on the right I don’t think there’s a standard name, but here’s why I think it should be called double super factorial or super double factorial. Super The post...

John    Edmond Laguerre came up with a method for finding zeros of polynomials. Unlike Newton’s method for finding zeros of general functions, Laguerre’s method is specialized for polynomials. Laguerre’s method converges an order of magnitude faster than Newton’s method, i.e. the error is cubed...

John    In the context of medical data, Safe Harbor typically refers to the Safe Harbor provisions of the HIPAA Privacy Rule explained here. Breach Safe Harbor is a little different. It basically means you’re off the hook if you breach encrypted health data. But not necessarily. More on that below. I’m...

John    Marc Stevens gave an example of two alphanumeric strings that differ in only one byte that have the same MD hash value. It may seem like beating a dead horse to demonstrate weaknesses in MD , but it’s instructive to study the flaws of broken methods. And despite the fact that MD has been broken...

John    Eric Lengyel’s new book Projective Geometric Algebra Illuminated arrived yesterday and I’m enjoying reading it. Imagine if someone started with ideas like dot products, cross products, and determinants that you might see in your first year of college, then thought deeply about those things for...

Wayne Joubert    Lately I’ve been helping a colleague to add worker threads to his GUI based Windows application. Thread programming can be tricky. Here are a few things I’ve learned along the way. Performance. This app does compute intensive work. It is helpful to offload this very compute heavy work to a worker...

John    One way to approximate Ï is to find the areas of polygons inscribed inside a circle and polygons circumscribed outside the circle. The approximation improves as the number of sides in the polygons increases. This idea goes back at least as far as Archimedes BC . Maybe you’ve tried this....

John    Suppose you have a cable of length s suspended from two poles of equal height a distance x apart. Assuming the cable hangs in the shape of a catenary, how much does it sag in the middle If the cable were pulled perfectly taut, we would have s x and there would be no The post How much will...

John    The word Mississippi has a unique pattern of letters. If you were solving a cryptogram puzzle and saw ZVFFVFFVCCV you might guess that the word is Mississippi. Is the pattern of letters in Mississippi literally unique or just uncommon What is the shortest word with a unique letter pattern The...

Wayne Joubert    million scientific papers have been published since . Assuming you can actually find the information you want in the first place how can you organize your findings to be able to recall and use them later It’s not a trifling question. Discoveries often come from uniting different obscure...

John    Surprise index Warren Weaver introduced what he called the surprise index to quantify how surprising an event is. At first it might seem that the probability of an event is enough for this purpose: the lower the probability of an event, the more surprise when it occurs. But Weaver’s notion is...