# Items tagged with mathmath Tagged Items Feed

### constructing a special function...

April 17 2014
1 5

Hi all;

Hope all of you  be in good health

I want to construct a special function b_{nm}(t) like:

with piecewise command i did it but the result is incorrect.

any one can help me to do it?

Best wishes

Ph.D Candidate

Applied Mathematics Department

### Minimization Process...

April 04 2014
1 12

Hi all

I have the following segment of maple program which belongs to time delay systems dynamic. here C=X-X0-G.Z-X.Dtau.P+X.Dtau.Z-U.P, is a matrix(vector) which comes from reordering the system terms and my goal is to minimizing J:=X.E.Transpose(X)+U.E.Transpose(U), subject to constraint C=0, but i don't know how to do so.

I will be so grateful if anyone can guide me

best wishes

Ph.D Candidate

Applied Mathematics Department

 > restart: with(Optimization): with(LinearAlgebra): macro(LA= LinearAlgebra): L:=1:  r:=2:  tau:= 1: interface(rtablesize= 2*r+1): Z:= Matrix(      2*r+1, 2*r+1,      [tau,       seq(evalf((L/(2*(iz-1)*Pi))*sin(2*(iz-1)*Pi*tau/L)), iz= 2..r+1),       seq(evalf((L/(2*(iz-1-r)*Pi))*(1-cos(2*(iz-1-r)*Pi*tau/L))), iz= r+2..2*r+1)       ],      scan= columns,      datatype= float[8] );                          Dtau00:= < 1 >: Dtau01:= Vector[row](r): Dtau02:= Vector[row](r): Dtau10:= Vector(r): Dtau20:= Vector(r): Dtau1:= LA:-DiagonalMatrix([seq(evalf(cos(2*i*Pi*tau/L)), i= 1..r)]): Dtau2:= LA:-DiagonalMatrix([seq(evalf(sin(2*i*Pi*tau/L)), i= 1..r)]): Dtau3:= -Dtau2: Dtau4:= copy(Dtau1): Dtau:= < < Dtau00 | Dtau01 | Dtau02 >,          < Dtau10 | Dtau1  | Dtau2  >,          < Dtau20 | Dtau3  | Dtau4  > >;   P00:= < L/2 >: P01:= Vector[row](r): P02:= Vector[row](r, j-> evalf(-L/j/Pi), datatype= float[8]): P10:= Vector(r): P20:= Vector(r, i-> evalf(L/2/i/Pi)): P1:= Matrix(r,r): P2:= LA:-DiagonalMatrix(P20): P3:= LA:-DiagonalMatrix(-P20): P4:= Matrix(r,r): P:= < < P00 | P01 | P02 >,       < P10 | P1  | P2  >,       < P20 | P3  | P4  > >; interface(rtablesize=2*r+1):    # optionally J:=Vector([L, L/2 \$ 2*r]):      # Matrix([[...]]) would also work here E:=DiagonalMatrix(J); X:=  Vector[row](2*r+1,symbol=a); U:=Vector[row](2*r+1,symbol=b); X0:= Vector[row](2*r+1,[1]); G:=Vector[row](2*r+1,[1]); C:=simplify(X-X0-G.Z-X.Dtau.P+X.Dtau.Z-U.P);
 (1)
 > J:=X.E.Transpose(X)+U.E.Transpose(U);
 (2)
 > Minimize(J,{C=0});
 Error, (in Optimization:-NLPSolve) invalid arguments
 > #XP:=-.015+X[1]+add(X[l+1]*f1(l)+X[r+l+1]*f2(l), l= 1..r): #plot([XP,T1], t= 0..1);#,legend= "Solution Of x(t) with r=50"):
 >
 >
 >
 >

### How do I express a function as a variable in Maple...

March 31 2014
3 4

I am new user of Maple. I have an expression like f(x,y)/g(x,y) and I want to have Maple name f(x,y) as something simple like "h" so that later equations write h/g(x,y) instead of the complete f(x,y)/g(x,y), and also to be able to simplify other equations in terms of h.

For example, a=(x+1)(y-5)^2/(x+y-3). Can I get Maple to let h=(x+1)(y-5)^2, so that I get h/(x+y-3) when I ask for a?

Sorry if this question is basic (and my math terminology incorrect), but I have been trying for a while.

### A command like fmincon command(matlab) in maple...

March 30 2014
0 2

Hi all

In matlab software we have a command namely fmincon which minimizes any linear/nonlinear algebric equations subject to linear/nonlinear constraints.

Now my question is that: what is the same command in maple?or how can we minimize linear/nonlinear function subject to linear/nonlinear constraints in maple?

thanks a lot

Ph.D Candidate

Applied Mathematics Department

### Generate Surface using PDE Method...

March 29 2014
0 0

Does anyone has any maple worksheet that generate surface using the PDE method described in this article?  I am trying to learn this method but I am not familiar with the mathematics to do it although the paper gives some description of it.  I hope someone can demonstrate the procedure in Maple.  Thanks

http://www.researchgate.net/publication/259095177_Automatic_shape_optimisation_of_pharmaceutical_tablets_using_Partial_Differential_Equations/file/72e7e52a87ed129d4a.pdf

### How do I prettyprint a summation with conditions?...

March 19 2014
0 5

Is there any simple way to print the sum of a series with exceptions?

For example, the following works (sort of), but its not consistent with mathematical notation, where one would expect to see something like a Sigma^' printed out, and the condition, alongw ith ther limits appear under the Sigma sign:

[Sum(1/(k^2-p),k=0..infinity),And(k<>p)]

### problem with system of ode's or maple ?...

March 19 2014
0 2

hi all.
i have a system of ODE's including 9 set of coupled OED's .

i have  converted second deravaties to dd2 , in other words : diff(a[i](t),t,t)=dd2[i](t) . i =1..9 :

and i have set these 9 equations in form of vibrational equations such :  (M.V22)[i]+(K(t).V(t))[i]+P(t)[i] = eq[i] , where M is coefficient Matrix of second  derivatives , V22 is Vector of second derivaties , for example V22[1] = diff(a[1](t),t,t) , and  P(t) is the numeric part of equations ( they are pure number and do not contain any symbolic function ) and K(t).V(t) is the remaining part of equations such that : (K(t).V(t))[i] = eq[i] - (M.V22)[i] - P(t)[i]  , and V(t) are vector of a[i](t)'s which V(t)[1] = a[1](t) ,

i have used step by step time integration method (of an ebook which i have attachted that part of ebook here), when i set time step of solving process to h=0.01 , i can solve this system up to time one second or more, but when i choose h=0.001 or smaller, the answer diverges after 350 steps . i do not know whether the problem is in my ODS system, or maple can not handle this ?the answer about the time t=0.3 are the same in both steps, but after that, the one with stpe time h=0.001 diverges. my friend has solved this in mathematica without any problem, could any body help me ?! it is urgent for me to solve this problem,thnx everybody.

ebook.pdf  step_=_0.001.mw  step_=_0.01.mw

### how to get 2 solutions from Maple equation which c...

March 17 2014
1 4

restart;
g:=0.88641:
e:=2.53128:
eq:=tan(g)= e*sin(f)/(1+e*cos(f)):
fsolve(eq,f);

gives  1.19749

What command/option do I need to get both solutions like with Mathematica:

g = 0.886461;
e = 2.53128;
eq = Tan[g] == (e Sin[f])/(1 + e Cos[f]);
NSolve[eq, f]

(*   {{f -> -2.56623}, {f -> 1.19756}} *)

thanks

### How do I best treat "delta" in Maple?...

February 09 2014
0 14

In physics as in math, we often use delta to indicate a (small but finite) variation in a parameter (e.g. delta x). Sometimes Delta (capital delta) is used for a larger variation, and there are even constructs like delta Delta x (a small variation of a larger variation in x). (Don't laugh or frown, this is being done & makes sense in certain situations.)

How do I write this best in Maple, esp. when I use 2-d math and am working on a (live-) script that may be handed out to others incl. students,? I.e. the appearance matters. Just writing delta x is interpreted (in 2-d input) as delta*x which is not what is meant (and leads to funny effects after the first simplify). If I write deltax (one word) then delta does not typeset in its proper greek form, which becomes an issue if you have many of these. I can write delta(x) and that often works (as long as you don't try to differentiate by x), but the typeset equation does not look right either (delta is not a function of x).

Is there a god way of doing this, or am I hitting a wall here?

TIA,

Mac Dude

### How to replace D-notation with standard partial de...

February 02 2014
1 12

I am trying to illustrate the chain rule for multivariet functions

diff(f(u(x,y),v(x,y),x)

The Maple responce is D1(f)(u(x,y),v(x,y)*(partial of u(x,y) wrt x) +..etc

I would like to replace the D- notation with the standard notation for the "partial of f wrt u" for obvious reasons - this is what students are familar with. The convert cmnd Doe Not Work in this case.

Similarly the cmnd diff(u(x,y),v(x,y),x,x) gives rise to D1,D11, D12 symbols which I would likee to convert to standard partial notation.

All this is a BIG DEAL when trying to illstrate the chain rule in Cal III.

Joe Salacuse

Mathematics

Kettering University

### Slides of VII Workshop 2014...

January 08 2014 Maple 17
4 1

Slides of the presentation at the VII Workshop Fast Computational and Applied Mathematics developed in graduate school at the National University of Trujillo. January 8, 2014.

Visualización_Geomét.pdf

L. Araujo C.

### Quick question about the solve function...

December 19 2013
1 5

EDIT:EDIT: I found what I was looking for. Thanks!

eq:=(V^(1-r/(r-s))*V*k/(r-2*s)+_C1)*V^(r/(r-s))=0;

$\left&space;(&space;\frac{V^{1-\left&space;(&space;\frac{r}{r-s}&space;\right&space;)}*V*k}{r-2*s}+C1&space;\right&space;)&space;*V^{\frac{r}{r-s}}=0$

solve(eq,C1);

Can anyone tell me why nothing happens when I solve the above equation for C1.

I've been coming across this problem a few times lately, but sometimes when the equations are less complicated it does work from time to time.

Any help would be greatly appreciated.

EDIT:  Thanks Markiyan Hirnyk

But I'm still having some trouble.

f:=t->(-r*t+s*t+V)^(r/(r-s));

eq2:=diff(C*f(t),t)+C*f(t)*r/(V+s*t-r*t)=s*k*t;

solve(eq2,C);

When I try solving eq2 nothing happens.

This time C is just a variable I used and not one Maple generated.

So why doesn't it work with this particular equation?

### Minimizing sum of functions...

December 07 2013
1 1

Hi. I'd like to find the solution closest to zero for sum(abs(f(k, m, n)+g(k, m, n)), n = i .. j) , when a < m, n < b .

Have trouble wrapping my head around how to do that and would appreciate any help.

Even better would be to find a solution where the maximum absolute value of f(k, m, n) + g(k, m, n) is minimized for n = i .. j) and when a < m, n < b , but I'm guessing the sum would be easier, and close enough.

Maybe I'm barking up the wrong tree getting this done with Maple, but I'm hopeful.

Thank you for looking

### Inert Mathematical Functions...

November 19 2013
8 0

Hi
In connection with recent developments in the Physics package, we now have mathematical typesetting for all the inert functions of the mathematical language. Hey! This is within the Physics update available on the Maplesoft Physics: Research & Development webpage

I think this is an interesting development that will concretely change the computational experience with these functions: it is not the same to compute with something you see displayed as %exp(x) instead of the same computation but flowing with it nicely displayed as an exponential function with the e in grey, reflecting that Maple understands this object as the exponential inert function, with known properties (all those of the active exp function), and so Maple can compute with the inert one taking these properties into account while not executing the function itself - and this is the essence of the inert function behaviour.

Introducing mathematical display, copy and paste for all these inert functions of the mathematical language concretely increases the mathematical expressiveness of the system, for teaching, working and also for presenting ideas.

Attached is a brief illustration.

Edgardo S. Cheb-Terrab
Physics, Maplesoft

### Maple T.A. takes math contest online, doubles numb...

November 18 2013 Maple T.A.
6 0

Maplesoft is a long standing supporter of the Who Wants to Be a Mathematician contest for high school students. For years, we have donated Maple as prizes to winners of the national and regional contests.

This year, being the 25th anniversary of Maplesoft’s incorporation, the company decided to support several projects that encourage the use of math amongst high school students and young adults. We dedicated a bigger budget towards projects that would enable us to make a significant impact on students and impress upon them the need for math and science in their future careers.

One project we undertook this year is giving an extreme makeover to the Who Wants to Be a Mathematician contest! With Maplesoft as a “Technology Sponsor”, the contest that was administered on pen-and-paper moved to a digital format. We donated our testing and assessment tool, Maple T.A. to administer the tests online, making the software accessible to every student that participated. This meant the students took an online test, and were automatically and instantly graded using Maple T.A.

The 2013 competition is underway, and the results are extremely positive:

• The number of students that participated in the contest doubled this year, with over 2000 students from over 150 schools participating.
• The competition introduced a second level of tests, making the competition more rigorous. After the first elimination round, eligible contestants moved to a second round with questions of increased difficulty levels.
• By avoiding much of the paper work and manual corrections, the organizers saw significant savings in time and money.

Custom test questions were created in Maple T.A., which were accessed by students from a server hosted by Maplesoft. The simple and easy to use interface of Maple T.A. enabled the students to take the test without spending time learning the tool. Maple T.A. supports the use of standard mathematical notation in both the question text and student responses. Maple T.A. also allows free-response questions, including questions that have more than one correct answer.

Who Wants to Be a Mathematician is a math contest for high school students, organized by the American Mathematical Society (AMS), as part of its Public Awareness Program. Ten students will be chosen for the semifinals and two will qualify for the finals to be held at the Joint Math Meetings in January 2014.

More information about the contest that is currently in progress can be found on the AMS website

 1 2 3 4 5 6 7 Last Page 1 of 35
﻿