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User: johnnyb

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  1. Anywhere where you have a second derivative where the variable with which you are taking the derivative with respect to is dependent on another variable. You would previously have to use Faa di Bruno's formula to properly take care of this situation. Now you can just do algebraic manipulations.

  2. I recently had another paper which sat for 4 MONTHS in the editors inbox, before he decided he just wasn't interested.

    What needs to happen is to have a small change in policy like this:

    1) You can submit to multiple journals at once
    2) A journal makes an offer to send it for review
    3) Accepting an offer @2 requires that you remove your submission from other journals

    Then the procedure goes on as before. This will prevent editors from wasting everyone's time.

    What's super-super frustrating is that I had a *different* paper that got rejected because it needed a proof of a result, but the proof was outside the scope of the first paper. So, I have a different paper that was waiting an extra 4 months because it needs this other paper to be reviewed first.

    The only reason I don't just self-publish everything is that peer review helps me convince myself that I'm not crazy.

  3. If you read my paper, I actually suggest this as a shortened form of my own. This notation is Arbogast's, and is woefully underused. I show how to interconvert between Arbogast notation and my own in the paper.

  4. Re:Summary's accuracy seems questionable on Old-School Slashdotter Discovers and Solves Longstanding Flaw In Basic Calculus (mindmatters.ai) · · Score: 1

    Not quite. d(1) *is* zero. The differential of a constant is zero, basically by definition. If e is an infinitesimal, 0/e is still zero. However, d^2x/dx^2 != d(dx/dx)/dx. d(dx/dx)/dx, using the new notation, is "d^2x/dx^2 - (dx/dx)(d^2x/dx^2)", which is obviously zero by inspection.

  5. Re: Seems quite a lot larger... on Old-School Slashdotter Discovers and Solves Longstanding Flaw In Basic Calculus (mindmatters.ai) · · Score: 2

    The problem with e-book math books is trying to make it look right on a small screen. If you just want a PDF of it, send me an email and I'll send you one, especially if you consider telling other people how great it is. Unfortunately, you can't just tell Amazon to take your PDF and make it an e-book :(

  6. Re:What about partial derivatives? on Old-School Slashdotter Discovers and Solves Longstanding Flaw In Basic Calculus (mindmatters.ai) · · Score: 4, Interesting

    I've actually got a second paper on partial derivatives just about ready to go. It was originally part of this paper, but it got a little long, and I wanted to rethink and clarify a few concepts. Anyway, partial differentials have the same notational problem *plus* one more. The problem is that there are several partial differentials which all go by the same name. Once you name them properly (i.e., give them each a distinct name) the problems go away.

  7. My coauthor has been doing this to good effect. His book "Controllability of Dynamic Systems: The Green's Function Approach" utilizes it. My role in mathematics is primarily in teaching high schoolers, so I don't spend a lot of time with differential equations. That's also the reason I *have* a co-author. I needed someone to tell me I wasn't crazy :)

  8. Re:Seems quite a lot larger... on Old-School Slashdotter Discovers and Solves Longstanding Flaw In Basic Calculus (mindmatters.ai) · · Score: 3, Interesting

    Except that, in the first derivative, it *is* used as a fraction. Otherwise you couldn't reformulate your equation for integration (i.e., you have to multiply both sides by dx, which is treating it as a fraction). So, to say that in one case, it is a fraction, but this next case it isn't, but still written as a fraction, even though it *could* be written as a fraction, but we just decided not to, seems strange, at least to me.

  9. You never did a second derivative test to determine whether you are at a local minima or maxima?

    Most intro calculus books at least show the notation for the second derivative. However, it is true that they rarely take it far enough to hit any problems with the notation.

    I actually figured this out while trying to find a good way to explain the notation to my students, which is a homeschool co-op class (I have a range of 9-12 graders - the 9th grader is an exception, but she is ridiculously smart). I read through numerous calculus textbooks trying to find the justification for the notation, and none of them even attempted it. So, I decided to try it out myself, and found out that the standard notation was wrong.

  10. Re:Seems quite a lot larger... on Old-School Slashdotter Discovers and Solves Longstanding Flaw In Basic Calculus (mindmatters.ai) · · Score: 5, Informative

    This is my thought as well. Interestingly, I developed this while writing a book (Calculus from the Ground Up) to use for my homeschool co-op calculus classes. I was trying to find a good way to explain the notation, and I literally had 20 calculus books that I read through trying to find a good explanation for the standard notation in any of them. None of them even attempted an explanation, just "this is the way it is, but don't treat it as a fraction." So, I tried to deduce the notation myself. That's when I realized that it was not just limited, it was actually wrong. So I wrote the paper and finished the book (it's Appendix B in the book).

  11. Re:Summary's accuracy seems questionable on Old-School Slashdotter Discovers and Solves Longstanding Flaw In Basic Calculus (mindmatters.ai) · · Score: 4, Interesting

    It's a bit of both. Some of the facts of the matter were known, but it was assumed that this was just "the way it was". That is, no one considered it an open problem. For instance, we view the inability to divide by zero just a fact of mathematics, not a flaw. Likewise, this was not known to be a flaw, it was just assumed that this was the way things worked.

    If you need to point to a definitive flaw, it was in our understanding of how it was supposed to work - the relationship between our understanding and the notation. Once *that* flaw was discovered, the actual notation just spilled right out. That is, the flaw was that people were *not* treating dy/dx *sufficiently* as a fraction, due to 19th century preferences against infinitesimals. Once you realize that dy/dx really is a fraction, and has to be treated accordingly, everything automatically works.

    It's almost humorous because there was no real advanced work to do. Literally everything needed is available in intro calculus. The problem was (a) the mathematics community had a habit of *not* treating dy/dx as a fraction, and (b) new students who didn't know better were simply taught *what* to do, not *why* to do it, and continued to repeat the mistake for over a century.

  12. Thanks! I appreciate it. Given that this was my first peer-reviewed mathematics paper, I had no idea how long the process was. I submitted the paper over a *year* ago. The necessary changes were minor. But the actual time it took to go through the process was excruciating. I'm happy to finally be on the other side :)

  13. Re:Can anyone keep up all these bullshits? on Signs You're Doing Devops Wrong (infoworld.com) · · Score: 1

    Or it means "my sysadmins got bored and learned Python" or "sysadmins doesn't sound as cool as devops".

  14. Instead of a degree, try this on Ask Slashdot: "Real" Computer Scientists vs. Modern Curriculum? · · Score: 1

    I actually noticed this trend about 8 years ago, and wrote a book to solve it. The book is called Programming from the Ground Up. It is a Linux-based assembly language book, but also teaches a lot about systems programming in general, but without being too technical.

    For the other CS-oriented stuff that they don't teach, the two books you should get are how to design programs and Structure and Interpretation of Computer Programs. After that, I have written a series of articles to apply those ideas to "real" programming languages on IBM's developerWorks. You can find links to them here.

  15. Early Detection on Sniffing Out Cancer With Electronic Noses · · Score: 5, Informative

    The problem with early detection is that many diseases are actually benign in their early stages, and, when detected, their detection can actually cause more harm for the patient. For instance, early cancer detection increases the likelihood that the patient will start chemo. Some cancers wind up being handled by the body, but *all* chemo treatments harm patients. So, early detection sometimes leads to more harm than benefit (plus an unfortunate issue with "success" rates - the cancer treatments get to include in their "success" count cancers that the body would have cleaned up anyway).

  16. Re:Still profitable.. on Oregon Withholding $25.6M From Oracle Over Health Website Woes · · Score: 1

    "Or are those contracts written so horribly that the company gets paid for a nonfunctional product?"

    The problem is that a lot of these types of contracts are written with a clause such that launching them publicly is an implicit acceptance of the project as a finished product. So, since they at least tried to launch it, that means that the project is "finished", and everything else is billed hourly on top of it.

  17. Re:Oracle Services on Oregon Withholding $25.6M From Oracle Over Health Website Woes · · Score: 2

    It has been over a decade since I last worked with Oracle, so things may have changed. But when I worked on an Oracle project, it cost a huge amount of money, took way too long, didn't work well, and required double the number of staff to manage the application. After Oracle left, a second company came along behind who specializes in fixing stuff that Oracle broke. This company, I don't remember its name, literally does its business as cleaning up Oracle's trash. They didn't even promise good results, only "I know how much pain you are in, we'll make it not hurt quite so much." Interestingly, this particular project wound up as a "success story" on Oracle's website.

  18. Sounds Nice on Oregon Withholding $25.6M From Oracle Over Health Website Woes · · Score: 3, Interesting

    Must be nice to be able to fail at a project such that they owed you $69 million, but you don't actually have to make it work.

    Perhaps states should make a rule stating that large projects must be broken up into deliverables of $1 million increments.

  19. Does Everything Have to Be Electronic? on Ask Slashdot: Printing Options For Low-Resource Environments? · · Score: 1, Insightful

    I know everyone wants an electronic everything, but it sounds like in your situation paper records may actually be optimal. If you have to have a paper system in place anyway, why do the added expense of going digital as well? Sometimes, what is really needed is to optimize the paper system, rather than replace it with an electronic one.

  20. Re:And now Google Drive is down... on Ask Slashdot: Which Google Project Didn't Deserve To Die? · · Score: 0

    iCloud is a useless service. It intended to compete with DropBox, I think, and failed miserably. I think iOS developers should all individually opt to develop for DropBox rather than iCloud.

  21. Re:And now Google Drive is down... on Ask Slashdot: Which Google Project Didn't Deserve To Die? · · Score: 1

    AWS has actually been pretty good if you actually do a proper deployment. I can only think of one time when they had multiple availability zones down at the same time. If you don't deploy across multiple availability zones, then it is just like any other hosted service. I often use it that way, too, it just isn't the magic fix-it-all system if you don't use it like it is intended.

  22. Curious as to the Effectiveness on "Lazarus Project" Clones Extinct Frog · · Score: 4, Insightful

    It will be interesting to see how effective this is. DNA is not the sole source of information for an organism's morphology. Nuclear transfer has shown some traits which are not dependent on DNA. It will be very interesting to compare the morphology of the final organism to the original, extinct species.

  23. Peter Jackson? on Interactive Tool Visualizes Tolkien's Works · · Score: 4, Funny

    By "creating a LotR visualization tool", does that mean they have cloned Peter Jackson?

  24. Can they get me on Lab Rats Given "Sixth Sense" · · Score: 3, Funny

    The ability to sense when my children are misbehaving? That would be more helpful than infrared, I think.

  25. Re:Monsanto takes .. on Monsanto Takes Home $23m From Small Farmers According To Report · · Score: 1

    But the seeds naturally produce other seeds. That is what seeds do. Did the farmer sign an agreement stating that they would not re-gather the seeds? If not, I don't see how Monsanto has a case. They sell seeds. The natural result of a seed is to produce more seeds. That would be like selling someone a printer and then coming back and claiming copyright on everything it prints.

    If, however, the farmer signed an agreement, then I think the stupid person is just the farmer, and Monsanto is just taking advantage of fools.