<

Thomas Richard

Mr. Thomas Richard

2633 Reputation

12 Badges

12 years, 159 days
Maplesoft Europe GmbH
Technical professional in industry or government
Aachen, North Rhine-Westphalia, Germany

MaplePrimes Activity


These are replies submitted by Thomas Richard

@manon22lr This implicit solution cannot be turned into an explicit one. It's not a weakness of dsolve, but simply because y(t) appears both inside ln and arctan.

What you can get is a series expansion as follows:

lambdaS:=dsolve(ivp,y(t),'series');
odetest(lambdaS,ivp,'series');
lambdaP:=convert(lambdaS,'polynom');

It reveals how a and eta impact the result - which should be useful for your further parameter studies.

 

I also like your worksheet (thumbs up), and I'm sure it was fun to create. However, entering all these equations and figuring out the details of the animation sequences can become tedious, in my opinion.

An alternative approach is MapleSim which (essentially) "knows" the component equations and lets you focus on the Physical Modeling. For multibody mechanisms, it generates the animation on-the-fly, and lets you export it into various video formats. Have you taken a look at the Jansen two-legs example (https://www.maplesoft.com/products/maplesim/ModelGallery/detail.aspx?id=153) in our Model Gallery?

@vv Here's another value resulting in a reducible polynomial: k=(475/2187)^2, found in a double loop over small numerators and denominators up to 10000 (not just squares, so it took some time)..

While the general answer to the OP's question is "no", there are still interesting cases that he could investigate.

@vv Indeed. Same for k=25/9 that I found just now.

Edit: the case k=64/81 is also solvable, but gives a lengthy output...

@vv That's right. Some further k values are 0, 1/2 and 1/81.

I have deleted some of your posts due to unacceptable and insulting language. Please see https://www.mapleprimes.com/help/guidelines.

@DoingMath2018 See the help page ?sum,details for background info:

s := sum((-1)^n/n*x^n, x=1..infinity,parametric);

 

@rameen hamood Use the green arrow-up button of the message editor. The dialog that opens should be self-explanatory.

The idea of this forum is not about doing someone's homework.

At the very least, show us what you have done in Maple so far, and upload your worksheet (even if incomplete). If you run into problems, please describe them as precisely as possible, and we may be able to help you.

@gawati2611 Try this:

f := unapply(Determinant(M),w1,w2);

The difference between this and your function definition is explained on the unapply help page.

I got a similar question from another customer today, and it turned out that he just needed to load one of the Units packages (recommended is Units[Simple]) to add the expressions.

@nm In addition, the simplified representation appears to be (a bit) longer, but is easier to check:

ot := odetest(sol,ode);
convert(ot,'exp');
ssol := simplify(evalc(sol)) assuming x>0;
odetest(ssol,ode);

 

@Carl Love No, that cannot be turned off, AFAIK.

@acer That feature was acutally introduced in Maple 13.02, if I recall correctly. So the OP might even benefit from it.

@Anthrazit I have deleted the attachment because it contains your Purchase Code. That is valuable information (for you) and should never be published. Please consider uploading a shortened file. Thanks.

4 5 6 7 8 9 10 Last Page 6 of 35