Alexey Ivanov

## 485 Reputation

4 years, 357 days

## What are the criteria for the selection ...

Can anyone explain what are the criteria for the selection of works to the Maple Application Center?
For example, my suggestion for placement in the Application Center is dedicated to the universal method of kinematic analysis of linkages.
http://www.mapleprimes.com/posts/204684-Lever-Mechanisms-
This is a very powerful numerical method that allows calculate the linkages with any number of degrees of freedom. Description and application examples were sent to the Application Center Maple February 14, 2017, and since then I cannot understand or know why this method does not appear there.
At the same time I was asked to put an example of rolling without slipping on Mobius strip.
http://www.mapleprimes.com/posts/207879-Rolling-Without-Slipping-On-A-Nonorientable
(And at this time the sample is already in Application Center.)
It seems to me that the Rolling can be attributed, rather, to toys and to fun and a little to the training in Maple. But the kinematic analysis of linkages is a very serious work, and has the potential to develop super CAD of linkages.
CAD of linkages with such capabilities as far as I know, does not exist yet.

Why is this so?

## To paint a triangle on a sphere...

Maple 15

My profile picture was formerly animation and looked like this:

It would be interesting to paint a triangle on a sphere. How can I do that?

## Mathematica vs Maple...

Maple

Inspired by the theme
http://www.mapleprimes.com/questions/219995-Finding-A-Convinient-Parametrization-Of-Surfaces
Examples in the Mathematica did Alexander Bannikov.
It is equidistant radius 0.1 to the surface

(x1 ^ 2 + x2 ^ 2-0.4) ^ 2 + (x3 + sin (x1 * x2 + x3)) ^ 4-0.1 = 0;

and an example of parameterization the same surface

https://vk.com/doc7819263_439432143?hash=36cf31d52c97e2e373&dl=7e4fa17a771dffb331

As I have understood from the words of Alexander Bannikov, parameterization was performed using the functions: RegionFunction, ContourPlot3D, ClippingPlanes.

It turns out that Maple functions inferior?

## ODE boundary value problem ...

It is known that ODE boundary value problem is similar to the problem of solving systems of nonlinear equations. Equations are the boundary conditions, and the variables are the values of the initial data.
For example:

y '' = f (x, y, y '), 0 <= x <= 1,

y (0) = Y0, y (1) = Y1;

Where y (1) = Y1 is the equation, and Z0 is variable, (y '(0) = Z0).

solve () and fsolve () are not directly suitable for such tasks. Directly should work the package of optimization in relation to a system of nonlinear equations. (Perhaps it has already been implemented in Maple.)
Personally, I am very small and unprofessional know Maple and cannot do it. Maybe there is someone who would be interested, and it will try to implement this approach to solving ODE boundary value problems?

## RootFinding[Isolate] vs solve...

Maple

For solving polynomial systems I used RootFinding[Isolate]. But after discussing the question http://www.mapleprimes.com/questions/211774-Roots-Of--Expz--1
I decided to compare Isolate and evalf(solve ([...], [...])). It seemed to me that solve some convenient. The only if in the equation there are integers as a real, they should be recorded with a decimal point. (For real solutions of this procedure should be used with (RealDomain).)  Examples:

SOLVE_ISOLATE.mw

I wonder why then the need Root Finding [Isolate]?

 1 2 Page 1 of 2
﻿