Maple Questions and Posts

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I want to divide every element of A1 list by every element of list A2. Lists are unequal length.

Example:

A1:= [a1, a2, a3];

A2:= [b1, b2];

Output would be:

[a1/b1, a2/b1, a3/b1, a1/b2, a2/b2, a3/b2]

I managed to do this by this means:

LinearAlgebra:-OuterProductMatrix([a1, a2, a3], [1/b1, 1/b2]); convert(%, list)

My questions are:

  1. Is there a more succinct, practical method?
  2. How about if I want to use a different operation like say adding or just use a function f?

Thank you all in advanced.

I've been using the following syntax to set boundary condition which is a derivative, when passing it to pdsolve. Say we want to set u(r,theta,t) to have insulated boundary conditions at r=1. So the BC will be

For example, to set derivative of u w.r.t. "r" to zero when r=1

       eval(  diff(u(r,theta,t),r), r=1) = 0;  #(1)

or using this syntax

       D[1](u)(1, theta, t) = 0;  #(2)

But now I find, on one example below, that the above no longer works.  I have to use this syntax (which I did not know about) for it to work

        D[1]*u(1, theta, t) = 0;  #(3)

Has something changed? why when using (3) pdsolve now gives result, but when using (2) or (1) it returns unevaluated? are the three semantically equivalent? when to use which syntax?

I am using Physics updates 265, Latest Maple 2018.2 

Here is an example showing the (1,2)  syntax no longer works, but the (3) syntax works

#articolo example 6.9.2
restart;

#using (1) syntax
pde := diff(u(r, theta, t), t) = (diff(u(r, theta, t), r)+r*(diff(u(r, theta, t), r, r))+(diff(u(r, theta, t), theta, theta))/r)/(25*r);
bc_on_r := eval(diff(u(r,theta,t),r), r=1) = 0;
bc_on_theta:= u(r,0,t)=0, u(r,Pi,t)=0;
ic := u(r,theta,0)=(r-1/3*r^3)*sin(theta);
pdsolve([pde, bc_on_r,bc_on_theta,ic], u(r, theta, t), HINT = boundedseries(r = [0]))

does not solve it.

restart;

#using (2) syntax
pde := diff(u(r, theta, t), t) = (diff(u(r, theta, t), r)+r*(diff(u(r, theta, t), r, r))+(diff(u(r, theta, t), theta, theta))/r)/(25*r);
bc_on_r := D[1](u)(1, theta, t) = 0; 
bc_on_theta:= u(r,0,t)=0, u(r,Pi,t)=0;
ic := u(r,theta,0)=(r-1/3*r^3)*sin(theta);
pdsolve([pde, bc_on_r,bc_on_theta,ic], u(r, theta, t), HINT = boundedseries(r = [0]))

does not solve it.

restart;

#using(3) syntax
pde := diff(u(r, theta, t), t) = (diff(u(r, theta, t), r)+r*(diff(u(r, theta, t), r, r))+(diff(u(r, theta, t), theta, theta))/r)/(25*r);
bc_on_r := D[1]*u(1,theta,t)=0;
bc_on_theta:= u(r,0,t)=0, u(r,Pi,t)=0;
ic := u(r,theta,0)=(r-1/3*r^3)*sin(theta);
pdsolve([pde, bc_on_r,bc_on_theta,ic], u(r, theta, t), HINT = boundedseries(r = [0]))

I've used syntax (1) before many times and it works. Here is an example where all three syntax work

pde:=diff(u(x,t),t)=k*diff(u(x,t),x$2);
bc:=eval(diff(u(x,t),x),x=0)=0,u(L,t)=0;
ic:=u(x,0)=f(x);
sol:=pdsolve([pde,bc,ic],u(x,t));

pdsolve gives

 Using syntax (2)

pde:=diff(u(x,t),t)=k*diff(u(x,t),x$2);
bc:=D[1](u)(0,t)=0,u(L,t)=0;
ic:=u(x,0)=f(x);
sol:=pdsolve([pde,bc,ic],u(x,t));

gives same answer as (1) and using syntax (3)

pde:=diff(u(x,t),t)=k*diff(u(x,t),x$2);
bc:=D[1]*u(0,t)=0,u(L,t);
ic:=u(x,0)=f(x);
sol:=pdsolve([pde,bc,ic],u(x,t));

The answer also looks like different and simpler, but I assume they are equivalent for now without looking too much into it.

Which syntax should one use as now I am really confused.

It looks like (3) is the one that should be used? Why the others did not work on first example? i.e. pdsolve did not give an answer at all?  And if (1,2,3) syntax are supposed to be equivalent, whysecond example gives slightly different looking answer when using one syntax vs. the other?

 

And finally to make things more confusing, here is an example where syntax (3) does not work, but syntax 1 and 2 work:

#articolo example 8.4.3
restart;
pde := diff(u(x, t), t) = (1/20)*(diff(u(x, t), x, x))+t;
bc := u(0, t) = 5, (u(1, t)+ D[1](u)(1, t)) = 10;
ic:= u(x, 0) = -40*x^2*(1/3)+45*x*(1/2)+5;
pdsolve([pde, bc,ic], u(x, t))

gives answer.

restart;
pde := diff(u(x, t), t) = (1/20)*(diff(u(x, t), x, x))+t;
bc := u(0, t) = 5, (u(1, t)+eval(diff(u(x,t),x),x=1))  = 10;
ic:= u(x, 0) = -40*x^2*(1/3)+45*x*(1/2)+5;
pdsolve([pde, bc,ic], u(x, t))

gives same answer. But

restart;
pde := diff(u(x, t), t) = (1/20)*(diff(u(x, t), x, x))+t;
bc := u(0, t) = 5, (u(1, t)+ D[1]*u(1, t)) = 10;
ic:= u(x, 0) = -40*x^2*(1/3)+45*x*(1/2)+5;
pdsolve([pde, bc,ic], u(x, t))

does not work.

Clearly there is something I do not understand between these 3 syntaxes and when to use which.

Using 265 version

Physics:-Version()
 "C:\Maple_updates\Physics+Updates.maple", 2018, December 22, 

    10:41 hours, version in the MapleCloud: 265, version 

    installed in this computer: not installed


downloaded today.


 

In this code k=2 and Beta=2 has been cconsidered

Loading Optimization

Loading Student:-MultivariateCalculus

ISO ELASTIC DEM ADD ERROR

y := proc (p, e) options operator, arrow; alpha-beta*p+k*e end proc:

G := g(p):

NULL

g := proc (e) options operator, arrow; (1/2)*mu*e^2 end proc:

 

Lambda := proc (z) options operator, arrow; int((z-u)*phi(u), u = 0 .. z) end proc: 

``

``

NULL

Step 1  Integrated supply chain

THE EXPECTED total PROFIT FUNCTION w r t LINEAR DEMAND

 

PI := proc (p, e, z) options operator, arrow; (p-c)*(y(p, e)-z)-(p-v)*Lambda(z)-g(e) end proc

proc (p, e, z) options operator, arrow; (p-c)*(y(p, e)-z)-(p-v)*Lambda(z)-g(e) end proc

(1)

PI(p, e, z)

(p-c)*(-beta*p+e*k+alpha-z)-(p-v)*(int((z-u)*phi(u), u = 0 .. z))-(1/2)*mu*e^2

(2)

FIRST PUT ALL PARAMETER VALUES AND THEN GO FOR THE DIFFERENTIATION

RUN THE OPTIMALITY AND THE SUBROUTINES FOR DIFFERENT Beta and K values

CASE 1:   Put k = 2 and beta =2

beta

(3)

`` 
Int_Profit := simplify(eval(PI(p, e, z), [k = 2, beta = 2, alpha = 50, mu = 10, c = 5, v = 1, phi(u) = 1/2]))

-2*p^2+(1/4)*(-z^2+8*e-4*z+240)*p-5*e^2+(1/4)*z^2-10*e+5*z-250

(4)

Int_Profit[1][1]

(-2*p^2+(1/4)*(-z^2+8*e-4*z+240)*p-5*e^2+(1/4)*z^2-10*e+5*z-250)[1][1]

(5)

 

Optimization:-NLPSolve(Int_Profit, p = 0 .. 60, e = -1000 .. 30, z = -10000 .. 25, initialpoint = {e = 0, p = 10, z = 0}, maximize)

[230.512568949745969, [e = HFloat(2.274015113534025), p = HFloat(16.370075567375324), z = HFloat(-1.4795080892429795)]]

(6)

NULL

Int_Profit

-2*p^2+(1/4)*(-z^2+8*e-4*z+240)*p-5*e^2+(1/4)*z^2-10*e+5*z-250

(7)

Calculate the Value of q

``

q := z+y(p, e)

-beta*p+e*k+alpha+z

(8)

qopt := simplify(eval(q, [e = 2.27401511353403, p = 16.3700755673753, z = 1.47950808924298, k = 2, beta = 2, alpha = 50, mu = 10, c = 5, v = 1, phi(u) = 1/2]))

23.28738718

(9)

Step 2  Decentralized supply chain

Retailer's profit

 

`#msubsup(mi("Π",fontstyle = "normal"),mi("R"),mi("d"))` := proc (p, e, q, w) options operator, arrow; (p-w)*(y(p, e)-z)-(p-v)*Lambda(z)-g(e) end proc

proc (p, e, q, w) options operator, arrow; (p-w)*(y(p, e)-z)-(p-v)*Lambda(z)-g(e) end proc

(10)

Re_Profit := simplify(eval(`#msubsup(mi("Π",fontstyle = "normal"),mi("R"),mi("d"))`(p, e, q, w), [alpha = 50, beta = 2, k = 2, mu = 10, c = 5, v = 1, phi(u) = 1/2, w = 10]))

-2*p^2+(1/4)*(-z^2+8*e-4*z+280)*p-5*e^2+(1/4)*z^2-20*e+10*z-500

(11)

Optimization:-NLPSolve(Re_Profit, p = 0 .. 60, e = -1000 .. 30, z = -10000 .. 25, initialpoint = {e = 0, p = 10, z = 0}, maximize)

[129.081143396165999, [e = HFloat(1.7075918734530873), p = HFloat(18.537959441958364), z = HFloat(-0.9736548233351249)]]

(12)

 

``

``

Optimal q value for decentralized supply chain

 

qd_opt := simplify(eval(q, [e = 1.70759187345309, p = 18.5379594419584, z = .973654823335125, k = 2, beta = 2, alpha = 50, mu = 10, c = 5, v = 1, phi(u) = 1/2]))

17.31291969

(13)

Manufacture's Profit

 

`#msubsup(mi("Π",fontstyle = "normal"),mi("M"),mi("d"))` := proc (p, e, q) options operator, arrow; (w-c)*qd_opt end proc

proc (p, e, q) options operator, arrow; (w-c)*qd_opt end proc

(14)

M_Profit := simplify(eval(`#msubsup(mi("Π",fontstyle = "normal"),mi("M"),mi("d"))`(p, e, q), [qd_opt = 17.31291969, alpha = 50, beta = 2, k = 2, mu = 10, c = 5, v = 1, phi(u) = 1/2, w = 10]))

86.56459845

(15)

Total Wholesale Profit

`#msup(mi("Π",fontstyle = "normal"),mi("d"))` := proc (p, e, q) options operator, arrow; M_Profit+R_Profit end proc

proc (p, e, q) options operator, arrow; M_Profit+R_Profit end proc

(16)

Whole_Profit := eval(`#msup(mi("Π",fontstyle = "normal"),mi("d"))`(p, e, q), [M_Profit = 86.56459845, R_Profit = 129.08114339616599])

215.6457418

(17)

step 3 find the t value

t := (In_Profit-R_Profit)/(w-c)

(In_Profit-R_Profit)/(w-c)

(18)

 

topt := eval(t, [w = 10, c = 5, In_Profit = 230.512568949745969, R_Profit = 129.08114339616599])

20.28628510

(19)

 

Hence range of t is 17.31 to 20.28

 

 

 


 

Download Code_1.mw

I have
a:=-(diff(x(t), t))^2*h^2/(x(t)^2-2*d*x(t)+d^2+h^2)^(3/2);
                       

How do you collect the denominator to get

Hoping to get your very own copy of Maple for Christmas? 

No, I'm not about to announce a sale. No crass commercialism allowed on MaplePrimes!  But we have created this handy-dandy letter for Santa that students can use to try to convince him to put Maple under the tree this year*.

 

 

Happy holidays from Maplesoft!

 

*Results not guaranteed, but we hope you will agree we made a valiant attempt. :-)

 

 

When I try to install (as an example) physics update using Maple 2018.2.1 on windows 10, it keeps hanging in the middle as shown above.

I closed Maple, starting again and tried again, same thing happens. I waited for more than 10 minutes and nothing happens.  I click on the install button in the clouds windows from Maple itself to install it as I always did.

 

Do others have problem installing this?  I'll try again in few hrs, it might be the Maple server is having some issues but thought to ask.

 

 

Hello,

given is the lower, partial differential equation. I have solved this (hopefully) correctly. I was given the tip to do in Maple a simple control in which the solution is inserted into the original equation. Since I'm quite inexperienced in maple, I would like to ask you for help on how I do that best!

Thanks a lot!

Basis equation:

Solution:


Could anyone explain why Maple doesn't calculate the Killing vectors for the metric below?

Thanks in advance!

killing2.mw

I try to solve ODE with conditions, but it give answer only without conditions:

SOT.mw

Thank you.

On the convex part of the surface we place a curve (not necessarily flat, as in this case). We divide this curve into segments of equal length (in the text Ls [i]) and divide the path that our surface will roll (in the text L [i]) into segments of the same length as segments of curve. Take the next segment of the trajectory L [i] and the corresponding segment on the curve Ls [i], calculate the angles between them. After that, we perform well-known transformations that place the curve in the space so that the segment Ls [i] coincides with the segment L [i]. At the same time, we perform exactly the same transformations with the equation of surface.

For example, the ellipsoid rolls on the oX1 axis, and each position of the ellipsoid in space corresponds to the equation in the figure.
Rolling_of_surface.mw

 

And similar examples:

Is there any facility to apply Finite Volume Method to Partial idifferential equation on MAPLE?
Any comand?

Any Code?

I know abut semilogpot - it gives a semilog scale on the horizontal axis.

Is there any way to get semilog scale on the vertical axis?

Season's greeting

Modify the procedure that implements the secant and tangent routines in such a way that instead of the number of iterations in the beginning give the given accuracy E, with which the approximation is to be determined.

As a result, the procedure should return the last approximation along with the iteration number.

===

===

 

I need help.


How can we remove 0=0 from the above by single comand if it lie in any position from the set?

 

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