Hello, I have a similary issue with the following post :

http://www.mapleprimes.com/questions/200835-Algsubs-With-Subscripts-And-Powers

In a constraint equation (in mechanics), I need to make these algebraic substitutions :

--> sqrt(xA1² + yA1²) =rF1 
--> arctan(abs(yA1)/abs(xA1)) = aF1
--> sqrt(xC1^2+yC1^2) = rBTP
--> arctan(abs(yC1)/abs(xC1))=a1

I try to do it with this code :

ListAlgsubs:={sqrt(xA1^2+yA1^2)=rF1,sqrt(xA2^2+yA2^2)=rF2,sqrt(xA3^2+yA3^2)=rF3, sqrt(xA4^2+yA4^2)=rF4,arctan(abs(yA1)/abs(xA1))=aF1,-arctan(abs(yA2)/abs(xA2))=aF2,pi+arctan(abs(yA3)/abs(xA3))=aF3,pi-arctan(abs(yA4)/abs(xA4))=aF4,sqrt(xC1^2+yC1^2)=rBTP,arctan(abs(yC1)/abs(xC1))=a1};
for i from 1 to nops(ListAlgsubs)
do Branch1Cons:=applyrule(op(i,ListAlgsubs),Branch1Cons)
end do:
Branch1Cons:= simplify(Branch1Cons);

I have tried with algsubs or applyrule but it wasn't successfull in both cases.

Do you have an idea how can I do to simplify my expressions ? and namely conduct a good use of applyrule function

I join an extract of my code in order to facilitate the troubleshooting.

example.mw

Thanks a lot for your help.

Dears, When I run calculation in Maple I found an error in matrices. See the file

Hi, I have 10 equation system and 10 unknown variables. I however, want to reduce the equations to 2 with two unknowns. I'm wondering how this could be done in maple. The variables are Y, q, y^d, y^*, y^x, H,  p^d, w, P and Pv. I intend to solve the equations for Y and w. 

Thanks in advance for your help. The maple file has also been attached.

Regards

Small_Open_Economy.mw

Hi,

i make an attempt to plot the solution to

Here is my code :

> with(plots); with(DEtools);
> ode1 := diff(x(t), t) = v(t); ode2 := diff(v(t), t) = -(.8*9.8)*v(t)/abs(v(t))-cos(t)^2;
> MODEL := {ode1, ode2}; VARS := {v(t), x(t)}; DOMAIN := t = 0 .. 150; RANGE := x = -1 .. 1, v = -5 .. 5; COLORS := [BLACK, BLUE]; IC1 := [x(0) = .5, v(0) = .25]; IC2 := [x(0) = 2.5, v(0) = 3];
> DEplot(MODEL, VARS, DOMAIN, RANGE, [IC1, IC2], stepsize = .1, linecolor = COLORS, scene = [t, x]);
>

and the message cannot evaluate the solution further right of .16015784, maxfun limit exceeded (see ?dsolve,maxfun for details)

Any other attemp has failed.

Have you got somme ideas

Thanks

Phil

As I am beginner in maple, how to verify Bianchi Identities?

For Riemannian manifold,

1) R(X, Y)*Z+R(Y, Z)*X+R(Z, X)*Y = 0 

2) ((∇)[X]R)(Y,Z)W+((∇)[Y]R)(Z,X)W+((∇)[Z]R)(X,Y)W=0

I am not getting how to define vector fields. From my previous question I understood defining vector fields particularly. From that post I tried to verify the proof, but I cant. Please tell me about how to define vector fields without taking examples.

Thank in advance.

Hi, does anyone know how to plot a Bode diagram (phase and amplitude plot)? I am not looking for preparation of data but rather for the technicality of producing a plot that looks like I want, given I have data in the right form (which in my case are three Vectors: frequency, amplitude and phase).

Below is a rough sketch of what I am looking for. Note that the amplitude is on a log scale. It would be acceptable having to take the log of the data "by hand" to allow both vertical scales to be linear (I'd just convert the amplitudes to dB). The important things are the common frequency scale (horizontal) and the separation of amplitude and phase. I know plots has  dualaxisplot, and I know I can use plots:-transform to move a curve around, but I want the two axes on the left side, below each other, rather on the left and right. I'd like the frequency scale in the middle between the two curves, although I could settle on that scale to be below both curves.

I had some look around the Maple applications but did not find anything looking like this.

Thanks,

Mac Dude

how to get maple to do linear algebra in Z_2 (integers modulo 2)

I don't want it to solve and then reduce mod 2 I want it to work over Z_2 so basis([ [1,1,1], [1,-1,1 ]) = [1,1,1]  etc

Hi,

a researcher at our department starts multiple Maple programs in parallel on our Linux servers.

Sometimes a high percentage of the resulting mserver processes hang. ps shows their state as

SNl (sleeping, multithreaded). strace to the processes shows that every one is waiting on a

futex without timeout. The problem occurs in versions 16 and 18. This is annoying.

Is there a fix for this?

Matthias Bauer

f := x^2*(y/x+sqrt(-7*y^2/x^2))/(y^2*(x/y+sqrt(-7*x^2/y^2)));
v := parametrization(f, x, y, t);

it can not parametrize.

i do not know which book teach group theory and algebraic curve

can we call this algebraic curve over finite field ?

how to represent a function as an algebraic curve equation for parametrization?

for i from 0 to 3 do print("rawData[", i, "] = new double[] { ", hello(i+1), ",", data[i+1], "};") end do

wrong format after copy to notepad from the maple 15

do not know why it insert a empty line, and make "};" in another line

and there is unexpected " 

wrong format example:

"rawData[", 0, "] = new double[] { ", 73.25, ",", 0.1510425143,

"};"
"rawData[", 1, "] = new double[] { ", 73.15, ",", 0.3974080269,

"};"
"rawData[", 2, "] = new double[] { ", 72.85, ",", 0.4661517269,

"};"
"rawData[", 3, "] = new double[] { ", 73.25, ",", 0.3974080269,

"};"

expected format:
rawData[0] = new double[] { 25.0, 20.0 };
rawData[1] = new double[] { 27.0, 34.0 };

Hello,

i did see that u can calculate minimial polynomials for for example \sqrt(2) or smth.

Suppose now u have a ground field K and an extension L=K(p,q) where p,q are some given rational functions in the indeterminates x,y, now i would like to calculate the minimal polynomial for lets say x+y or x over L which then obviously splits over the field K(x,y).

Thx in advance

Hi .please help me for solve this nonlinear equations , that attch below

thanks a lots.....

dsys3 := {8*(diff(f2(x), x, x, x, x))+9*(diff(f2(x), x, x))+10*f2(x)+11*(diff(f1(x), x, x, x))+12*(diff(f1(x), x))+13*(diff(f3(x), x, x))+14*f3(x)+f3(x)*f3(x)+(diff(f3(x), x))*(diff(f3(x), x))+(diff(f3(x), x, x))*f3(x) = 0, 16*(diff(f3(x), x, x, x, x))+18*(diff(f3(x), x, x))+19*(diff(f3(x), x, x))+22*(diff(f1(x), x))+23*(diff(f1(x), x))+24*(diff(f2(x), x, x))+25*f2(x)+26*f2(x)+27*f3(x)+29*f3(x) = 0, 2*(diff(f1(x), x, x))+3*(diff(f2(x), x, x, x))+4*(diff(f2(x), x))+6*(diff(f3(x), x))+7*f1(x)+(diff(f3(x), x, x))*(diff(f3(x), x))+(diff(f3(x), x))*f3(x)+(diff(f3(x), x))*f3(x) = 0, f1(0) = 0, f1(1) = 0, f2(0) = 0, f2(1) = 0, f3(0) = 0, f3(1) = 0, ((D@@1)(f2))(0) = 0, ((D@@1)(f2))(1) = 0, ((D@@1)(f3))(0) = 0, ((D@@1)(f3))(1) = 0}; dsol5 := dsolve(dsys3, 'maxmesh' = 500, abserr = .1, numeric, range = 0 .. 1, output = listprocedure)12.mw

Hi everyone,

I have a great problem with the evaluation of following definite integral

> restart;

> int((t-x)^2)/(1+2t+(1/2)t^2-ln(t^2+2t+2)t-ln(t^2+2t+2)+arctan(1+t)t^2+2arctan(1+t)t+ln(2)t+ln(2)-(pi/4)t^2-(pi/2)t)^2,t=0..x)

I have tried different classical commands but Maple doesn't give an answer. Probably, it's just a silly fault.

Does anyone knows how to solve it?

Thanks.

Hello everyone,

How can unknown values in boundary conditions of system ODEs be determine by using shooting technique. See the work sheet here Sht.mw

Thanks.

Hello;

I wish to express a tensorial equation or expression a simplified vector form.

In the worksheet attached, I was trying to express Maxwell Equations in the familiar vector form from the tensorial form, using the tensor.

But I cannot achieve the familiar tensor form. If someone can give a hand, it would help me a lot.

HowtoExpressCompactForm.mw