Tim Van Dusen

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17 years, 73 days

MaplePrimes Activity


These are answers submitted by Tim Van Dusen

Thanks Scott and JacqueC. I hope to write about some of the things you suggest, but I'm really terrible with wording my thoughts, so I'm going to have to try and do some organizing in my mind before I can convey them to others. It is a great subject matter though. Maple has, and continues to be a wonderful learning tool for me. I remember the first time I sat down with maple - as rediculous as it may seem to perhaps most, I actually got tears in my eyes, realizing the learning tool that I now had right at my fingertips. I remember a day when I was trying to make a buck by throwing chain on an oil rig down in the desert of New Mexico. Those were rough times for me. For those who may not know what it means to throw a chain on a rig, those who work on a rig are considered "rough necks" and the one who throws the chain usually also tends the motors - usually glorified cummins or cat engines - and is referred to as a "chain-hand". An additional job is to tend a flame that burns in a bucket at the end of a long pipe that comes out of the drilling hole and far away from the rig to burn off any flamable gas that may be encountered during the drilling process. Anyways, the rig is kinda like a small house up on stilts, and the crew that work it have barricks that they sleep in when they aren't on their shift. Sleeping conditions are really bad since the sound of the motors make it difficult to sleep, and there is always the danger of drilling into a pocket of h2s gas which requires immediate use of an oxygen mask so with that thought in mind it's tough to sleep. The chain hand grabs one end of a rather heavy chain and throws it around a pipe that's to be screwed into another pipe that's already in the hole in such a way that it wraps around itself, locks in place and then is pulled by the motors on the other end, essentially spinning the pipes together. A finger can be easily lost doing the job since it's kind of a synchronized thing in which the chain is thrown and the person controlling the motors begins the pull. If one gets out of sync then a finger can be lost in the links. To make matters worse, there is a huge tool, like a pipe-wrench on steroids, swinging overhead that then needs to be immediately fastened around the pipe afterwhich the motors give it a quick tug to snug the pipes even more, and the drilling continues. Anyhow... I said all that to explain how someone who wasn't using a whole lot of their brain power (that would be me) was stuck out in a place like that doing a job like that while all the time wishing I could make at least a little sense of the math that must have been required to control the drilling. The drilling is an interesting feat. Some may think that drilling is done straight down until a pool of oil is encountered and then it's pumped out, but that's not even close, at least not all the time. An oil company will set up a drilling platform on some land that they own and then drill over to and below someone else's property. I'm not sure how they pick the spot - perhaps on hear-say from one of the cattle ranchers that a dinosaur was spotted and died somewhere in the vicinity which could likely result in a little crude oil from the dying dino into the ground. What I found amazing is how they control the bending of the drill pipe in such a way that it goes straight down for 50' or so and then takes off in a horizontal position below the ground over to the property, that they don't own, but that contains the crude. What makes the task of controlling the drill pipe even tougher is that there are numerous pockets - some containing water and some just dried up undergound ponds. The pockets require filling in order to keep the drill pipe stabilized, so the drill needs to be pulled out of the hole and fill of some sort needs to be pumped in to fill the void. The fill is referred to as "mud" but isn't really dirt and water as some may assume it to be. It's interesting the way math is found in so many places. I wish I had learned a lot more at a young age. I'm very thankful to have resources such as Maple to help me now in the learning.
Thanks JacquesC - that's a great idea, but I'm not quite ready for that yet. I think that my non-curriculum learning of mathematics with Maple may be somewhat unique compared to some of the others who visit this board, so I've been trying to come up with an idea how to write about it in perhaps a book format. In the meantime I have a question or two to ask and may even be able to be of at least a little help to others and myself by participating in the answering of a couple. Sometimes I wonder if my participation here is a distraction or worthwhile to others. I hope it's at least a little of the latter since I know that digging for answers to some of the questions asked here helps me learn. Thanks again for the suggestion.
Is this what you're looking for? I got it from Maple Help. > with(StringTools); > seq(NthWord("abcde", i), i = 1 .. 20);
Is this what you're looking for? evalf(int(sin(x)*sin(x^3+x), x = 0 .. infinity)) = 0.2957412256 or symbolic: evalf(int(sin(x)*sin(x^3+x), x = 0 .. infinity)) = 0.2957412256 I'm pretty new to both calculus and Maple - so this may be very incorrect. Also, as for as I know, the result you'd get without the "evalf" is just the formula that's going to produce the result that you get with "evalf".
I'm not sure if this is the correct way to do this, but until someone more knowledgable jumps in, try this: x1 := [7, 11, 13, 17, 19]; x2 := [12, 14, 16, 18, 20]; y1 := [1, 2, 3, 4, 5]; with(plots): display(pointplot([seq([x1[i], y1[i]], i = 1 .. nops(y1))], axes = boxed, color = red), pointplot([seq([x2[i], y1[i]], i = 1 .. nops(y1))], axes = boxed, color = blue)); here's an example: http://2timv.com/math/maple/ListPlot/listPlot2.html
maple11 worksheet archived: http://2timv.com/math/maple/ListPlot/listPlot2.zip
I wanted to add - using a network packet snooper, I see that there is only local network traffic when Maple loads, so this really has me baffled how anything related to being connected to the internet could cause the question marks to appear. I'm still hoping for any ideas. The only reason I'm even interested in resolving this is because one of my latest installations of Maple is on a PC that is connected only occassionally to the internet via a dial-up modem. On that PC, the only workaround is to copy all the code into a text area before closing the worksheet and then copying it back as code wherever the question marks have appeared when I reload. It seems as though text is never effected by the curious question marks. I have an email into Maple support, but am hoping for suggestions from users before support has to devote much, if any of their time to it, as I'm sure that they are busy with much more important issues so I was hesitant about even bothering them with something like this.
I'm not sure how to do what you are asking, but until someone gets around to answering your question, I figured I might let you know what I do to get the correct printout. I just do the plots and whatever, then go in and add page breaks where I want separate pages. The page-breaks are added by the CTRL-B key combination in case you don't already know.
Or symbolically - and I'm not sure why the multiplication sign (after the s^s) is required for it to evaluate correctly. If you didn't already already have that, along with the missing "evalf" and was wondering why adding the "evalf" or just using the drop-down menu with "approximate" didn't produce the correct result - it has something to do with needing that multiplication sign. This may be a bug. I also noticed that even if I use the "Maple Math" to insert the symbolic here, the multiplication sign is removed. I inserted an image (I just recently figured out how to do that) into my message to show it as intended.
It just occured to me that we can put images in messages here so I'm going to try it. The following is just one of the images (the wave I deconstruct) from the HTML.
I figured out the first one using AnyNonZeros, but still don't know the answer to my second question.
I'd probably just use one or more global variables. Rather than show it here, below is a link to a webpage that shows it: http://www.math.sunysb.edu/~scott/Book331/Defining_functions_with.html If you need more, just google "maple global variables" without parenthesis.
I researched Microsoft's Virtual PC 2007, and although it's pretty neat, it still has quite a ways to go. Likewise with Vista. The biggest problem in my opinion with Vista is the lack of compatibility with both hardware and software. The talk around here is obviously Maple's compatibility, but my rather nice m-audio sound card won't even work with Vista, and if I had to choose the importance of one over the other, I'd choose the sound-card. I'm running one of the new Intel processors with as much RAM as WinXP can handle and Maple and everything else I'm using, runs pretty fast on that, so I really don't feel any urgency to move to Vista. I suppose the next time I upgrade my processor and decide to move up beyond the WinXP RAM limit, I may be ready for Vista and by that time I may also be in more of mood to change all my hardware and software to work with it. For now, I'm pretty satisfied with WinXP, and as always anxious to see what surprises await with the next version of Maple.
I made a couple of corrections to both the HTML and Maple 11 worksheet - a few typographical, and an increase of .0001 resolution in the area determination loop. 4-8-07 10:30am
Shift key plus ENTER key - is that what you're looking for?
While in document mode, right-click the mouse within the left margin area and select the option to "expand document block". Doing so, will show the entire results instead of just the final. I consider document mode to be a wonderful feature of maple with these kind of features. Tim
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