I would like to use Newton's Method (the multivariate one) in order to solve a system of equations. From what I understand, fsolve is essentially MAPLE's version of the multivariate Newton's Method. Is there a way to do the multivariate Newton's method any other way, other than fsolve? Also, is there a way to specify our own initial guess and tolerance for the Newton's Method and to get other details such as the number of iterations?

of the improper integral of exp((1-x)/((1-x)^2+y^2)) over the unit disk x^2+y^2 <= 1 with Maple? For purists the function is assumed to be undefined at (1,0). It is not so difficult to verify that statement  by hand. It is not easy to prove that with Maple.

My try was

f := evalc(exp(Re(1/(1-x-I*y))));

VectorCalculus:-int(f, [x, y] = Circle(`<,>`(0, 0), 1), numeric);

and

evalf(Int(f, [y = -sqrt(-x^2+1) .. sqrt(-x^2+1), x = -1 .. 1]));
.

Edit. The formula for f.                  

PS.

Hello everyone,

I am working on a program in Maple and got stuck in exchanging limits for integrals. For example, if I have an expression of following type.

Eq:=4*Int(f(x), x=0..1/3)+Int(x*f(x), x=0..2/3);

I want to convert it in to an expression of form

4*Int(f(x),x=0..x)-4*Int(y,x=1/3..x)+ Int(x*f(x), x=0..x)- Int(x*f(x), x=2/3..x)

In short, I want to split both the integral at x but flip in limits in the second integral. I tried as follows which did not work

applyrule(Int(f::anything,y=c::numeric..d::numeric)=Int(f,y=c..x)-Int(f,y=c..x), Eq)

Please, help me!

Thank you for your time.

How do i proceed to solve two differential equations?

Two equations two unknowns is easy to solve in polynomial algebraic equations. Example: x+y=5; x-y=3; The solution is x=4; y=1 by adding the equations we arrive at.

The two equations are second order differential equations with two variables say temperature T (x,y) and velocity c(x,y). Assume any simple equation (one dimensional as well i.e. T(x) and c(x) which you can demonstrate with ease, I have not formulated the exact equations and boundary conditions yet for SI Engine simulation.

Thanks for comments, suggestions and answers expected eagerly.

Ramakrishnan

Hey people,

I am trying to get the following code to run, but it keeps returning an error about too many arguments

restart:with(plots):with(PDEtools):
alpha_const := 0.5:gamma_const := 2.5: D1 := 0.05: D2 := 0.002:
A := diff_table(a(x,t)):B := diff_table(b(x,t)):
Selkov[1] := A[t] = 1 - A[]*B[]^(gamma_const) + D1*A[x,x]:
Selkov[2] := B[t] = alpha_const * ( A[]*B[]^(gamma_const) - B[]) + D2 * B[x,x]:

bc[1] := D[1](a)(0,t)=0: bc[2] := D[1](b)(0,t)=0: bc[3] := D[1](a)(4*Pi,t) = 0: bc[4]:=D[1](b)(4*Pi,t)=0:

ic[1] := eval(A[],t=0)=a_0:ic[2] := eval(B[],t=0)=b_0:
case1 := eval(ic,[a_0=1,b_0=1]):
case2 := eval(ic, [a_0=piecewise((x<2*Pi+1) and (x>2*Pi-1), 0.99, 1), b_0=piecewise((x<2*Pi+1) and (x>2*Pi-1), 0.99, 1)]):

Case1Default := pdsolve({Selkov[1],Selkov[2]},{bc[1],bc[2],bc[3],bc[4],case1[1],case1[2]},numerical);

Error, (in pdsolve/sys) too many arguments; some or all of the following are wrong: [{a(x, t), b(x, t)}, {a(x, 0) = 1, b(x, 0) = 1, (D[1](a))(0, t) = 0, (D[1](a))(4*Pi, t) = 0, (D[1](b))(0, t) = 0, (D[1](b))(4*Pi, t) = 0}, numerical]

My code worked just earlier today, and now it wont. If i try to run pdsolve({Selkov[1],Selkov[2]}) it says that there is an error with general case of floats. 

You help is greatly appreciated!

Hi,

I tried to use the Finance package and got:

with(Finance):
Warning, some commands in the Finance package may not work on this platform
Y := ItoProcess(1.0, mu, sigma, x, t);

Error, (in Finance:-ItoProcess) external linking: error loading external library finance.dll: The specified module could not be found.

Is it me or my pc that is causing this?

Thank you.

Murray

If I have some data, how would I determine the best normal distribution fit?

Hi Clever guys,
I am sorry if I asked for too much, but I am really in a big problem, I had a family problem and I didn't attend most of the lectures, and now I have to hand in an assignment before easter hollydays, and to be honest with you, I don't know from where to start, I know I will have to understand this stuff, but now I don't have enough time to do the assignment, so if anyone can help me, please please, for you guys it will maybe take 20min to do it, i ll need days and days and in the end it will be all wrong. I am going to try to do the other questions, there are 5 questions :(  
Please help me , I am really not a very bad student that just want to copie, but if nobody does this for me this time I will fell, please do this question for me please.. maybe you will say start it and then ask to check if it is correct, I am really trying my best, please.

that is one question:


By integrating a third order Newton Gregory Polynomial, derive Simpson’s

three eights rule given by

∫ f(x)dx (from x0 to x3 ) =3/8*ℎ(y0 + 3y1 + 3y2 + y3)

(b) Find the order of accuracy of Simpson’s rule and Simpson’s three eights rule.

thank you very much 

Hi,

Lets say we have some expression like

0.5* t^5 * r^-1 *V

is there some way in maple to determine the power of the variable t ?

My goal is to realize a procedure [lets call it PowerOfT() ]  , so that

PowerOfT( 0.5* t^5 * r^-1 *V) = 5

Thank you very much for your help.

I want to translate my maple code with matrice multiplication  to C code. But the command  "Multiply" cannot be translated. So I want to edit the function translation by myself. I use "AddFunction" command to create a new function  "Multiply" and want to specify its corresponding C code.

f := proc ()
local x,y;
x := Matrix([[1, 2], [3, 4]]);
y := Matrix([[1,3],[4,2]]);
Multiply(x, y);
NULL;
end proc;

LanguageDefinition:-Define("NewC", extend = "C", AddFunction("Multiply", [Matrix,Matrix]::Matrix,
proc (X, Y)
local a,b;
a := 2;
b := convert(a, string);
Printer:-Print("Mmultiply(", X);
Printer:-Print(",", Y, ")"); Printer:-Print("\n");
Printer:-Print("from", b, "to");
Printer:-Print(",", Y, "do") end proc, numeric = double));
Translate(f, language = "NewC")

But when I run it, the "Multiply" function cannot be translated.  The result is:

Warning, type signature [CodeGeneration:-Names:-ArrayType(integer,CodeGeneration:-Names:-ArrayRanges(1 .. 2,1 .. 2),CodeGeneration:-Names:-ArrayOptions()), CodeGeneration:-Names:-ArrayType(integer,CodeGeneration:-Names:-ArrayRanges(1 .. 2,1 .. 2),CodeGeneration:-Names:-ArrayOptions())] for function Multiply is not recognized
void f (void)
{
  int x[2][2];
  int y[2][2];
  x[0][0] = 1;
  x[0][1] = 2;
  x[1][0] = 3;
  x[1][1] = 4;
  y[0][0] = 1;
  y[0][1] = 3;
  y[1][0] = 4;
  y[1][1] = 2;
  Multiply(x, y);
  ;
}

I don't know why "Multiply(x,y)" cannot be translated.

If I put two "Multiply(x, y)" in the procedure, like this:

f := proc ()
local x,y;

Multiply(x, y);
x := Matrix([[1, 2], [3, 4]]);
y := Matrix([[1,3],[4,2]]);
Multiply(x, y);
NULL;
end proc;

LanguageDefinition:-Define("NewC", extend = "C", AddFunction("Multiply", [Matrix,Matrix]::Matrix,
proc (X, Y)
local a;
a := 2;
b := convert(a, string);
Printer:-Print("Mmultiply(", X);
Printer:-Print(",", Y, ")"); Printer:-Print("\n");
Printer:-Print("from", b, "to");
Printer:-Print(",", Y, "do") end proc, numeric = double));
Translate(f, language = "NewC")

THe result is:

Warning, cannot resolve types, reassigning x's type
Warning, cannot resolve types, reassigning y's type
Error, (in CodeGeneration:-IssueError) type 'Matrix' cannot be translated to target language

I don't know why type 'Matrix' cannot be translated.

how to customize/invert the foreground/background color scheme in Maple?

The black on white is killing my eyes and also wasting energy, white on black is much better on the eyes and conserves energy (pixel brightness), imho

thanks in advance!

Hello!

I performed a calculation where the output was a matrix that Maple said was too big to display explicitly. So, this output was just a summary. Specifically, something like this:

How can I save/export the data inside it to another matrix so that I can manipulate it while staying within Maple?

I can export to an external file using

and then reimport the data back into Maple. But this is cumbersome.

I can also see the data on my screen by double-clicking on the matrix. But I haven't been able to manage to copy & paste it within Maple or transfer it to another matrix so I can manipulate the data. How do I do this? I'd like to stay within Maple to avoid the hassle of exporting data to Excel & then reimporting it.

Thanks,

Damian.

given the following:

param:= {mu[2] = (1600), mu[4] = (1500)}
R := unapply(1/(1+exp((1/50)*x)), x);

prior := evalf(expand(eval(eval(R(abs(mu[4]-mu[2])), `` = (x->x)), param)));
   

I need to keep the paramaters encapsulated. I would like this last step to output the answer 0.1192029.... but the abs function doesn't let me

Hello I download maple2015 today but I dont know how can I work with it ?  how can I write math phrases?

Please help me soon!!!!

Maplesim 7.0(1) installer looks for Maple 18 installation.  Will Maplesim work with Maple 2015?

If not, what is the expected date of making both products compatible?

Regards,

G