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I am working in Document mode, 2D input.  I have doing some complex number evalutions

Lets say I have a complex number Z= 2+3i

when I ask maple for the "abs(Z)" I get the display of "abs(2+3i)" rather than the numberic answer. This occurs with all the complex operation arg, abs, polar conversion, 

polar(abs(2+3*i), argument(2+3*i))   this is from Maple. 

How do I display the numeric value for these functions in my document

 

Thanks Bill

Below z is made using different complex values on polar form, and I then need to express the resulting z on polar form with numeric values for length and angle.  However, I had no luck using evalc, evalf, or other I could find.

How can I convert z to a polar form with numeric arguments like shown below ?

How can I plot the complex function f(z)=1/(1-z) for |z|<1 into maple code? (z is a complex number)

 

Best regards,

Seda 

In plots made with 'complexplot3d', Maple uses by default a color wheel for the argument of complex numbers in which positive numbers are painted cyan and negative numbers are red. Is there a way to change this to the other common convention (i.e. cyan negative and red positive numbers)?

 

Any help would be really appreciated, as it's not convenient to have graphs made with different conventions in the same document and I wouldn't want to remake all the ones I already have.

I have problem to get real answer in a simple equation. maple just give me complex answer.

how i can get parametric real answer? Ihave trid this two way but not applicaple.

with(RealDomain); assume(T::real)

My code is:
Qz := 7.39833755306637215940309264474*10^7*sqrt(1/T)*(T-297.2)/T-16242.7935852035929839431551189*sqrt(1/T)/T;

q := (.6096*(299.2-T))/(sqrt(1.60000000000000000000000000000*10^(-9)-r^2)-0.346410161513775458705489268300e-4);

with(RealDomain); assume(T::real);

e := simplify(solve({0 = q-Qz}, {T}))

and the result like:

e := {T = 1/RootOf(-609600000000000000000000000000000000000000000000000000000+(879515018020273730453559011332895956000000000000000000000000000*sqrt(-625000000*r^2+1)-761682348615485390130551939524898425387968750740910059296172487)*Z^5+(-2959335021226548863761237057896000000000000000000000000000000*sqrt(-625000000*r^2+1)+2562859306691152293409465394507279449380503585614734443742000)*_Z^3+182392320000000000000000000000000000000000000000000000000000*_Z^2)^2}

dose anyone hase any opinion?

Greetings to all.

With the following matter I am betting on there being a simple mistake on my part due to fatigue owing to a challenging session of intense computing. The following link at Math.Stackexchange.Com points to a computation involving complex residues. Consult the link for additional details.

I usually verify my computations with Maple, I did the same this time. Thereby I happened on a curious phenomenon which I have documented below. Please study the session data provided, I believe it speaks for itself.

user@host:~$ math
Mathematica 10.0 for Linux x86 (64-bit)
Copyright 1988-2014 Wolfram Research, Inc.

In[1]:= Residue[z^2/(z^4 + 2*z^2 + 2)^2, {z, 2^(1/4)*Exp[3*Pi*I/8]}]

            1/8      1/4
        (-1)    ((-1)    + Sqrt[2])
Out[1]= ----------------------------
            1/4      1/4           3
        16 2    ((-1)    - Sqrt[2])

In[2]:= N[%]

Out[2]= 0.117223 - 0.0083308 I

In[3]:=
user@host:~$ maple
    |\^/|     Maple 18 (X86 64 LINUX)
._|\|   |/|_. Copyright (c) Maplesoft, a division of Waterloo Maple Inc. 2014
 \  MAPLE  /  All rights reserved. Maple is a trademark of
 <____ ____>  Waterloo Maple Inc.
      |       Type ? for help.
> residue(z^2/(z^4 + 2*z^2 + 2)^2, z=2^(1/4)*exp(3*Pi*I/8));
                                       0

> quit
memory used=0.9MB, alloc=8.3MB, time=0.07
user@host:~$

I am looking forward to learning what the correct syntax is to get the residue in this case and I hope I can assist other users who might have run into the same problem. I will cancel the question should it turn out to be trivial and of little potential use to the community.

Best regards,

Marko Riedel

Post Scriptum. Being a programmer myself I would be curious to learn more about the algorithms that are deployed here and how and why they did not succeed.

i have attcahed my ode with complex bvp

can anyone solved mine

NULL

restart

with(plots):

NULL

Eq1 := (11-10*d)*(diff(h(eta), eta))+2*f(eta) = 0;

(11-10*d)*(diff(h(eta), eta))+2*f(eta) = 0

 

(11-10*d)*(diff(diff(f(eta), eta), eta))-h(eta)*(diff(f(eta), eta))-f(eta)^2+g(eta)^2 = 0

 

diff(diff(g(eta), eta), eta)-h(eta)*(diff(g(eta), eta))-2*f(eta)*g(eta) = 0

 

diff(p(eta), eta)+2*(diff(f(eta), eta))-2*f(eta)*h(eta) = 0

(1)

NULL

NULL

`V&lambda;` := [0.5e-1, 1.5, 1.5]:

etainf := 3:

bcs := h(0) = 0, p(0) = 0, (D(f))(0) = lambda*f(0)^(4/3)/(f(0)^2+(1-g(0))^2)^(1/3), (D(g))(0) = -Typesetting:-delayDotProduct(lambda*f(0)^(1/3)*(1-g(0)), 1/(f(0)^2+(1-g(0))^2)^(1/3)), f(etainf) = 0, g(etainf) = 0;

h(0) = 0, p(0) = 0, (D(f))(0) = lambda*f(0)^(4/3)/(f(0)^2+(1-g(0))^2)^(1/3), (D(g))(0) = -f(0)^(1/3)*(1-g(0))*lambda/(f(0)^2+(1-g(0))^2)^(1/3), f(3) = 0, g(3) = 0

(2)

NULL

dsys := {Eq1, Eq2, Eq3, Eq4, bcs}:

for i to 3 do lambda := `V&lambda;`[i]; dsol[i] := dsolve(dsys, numeric, continuation = d); print(lambda); print(dsol[i](0)) end do

Error, (in dsolve/numeric/bvp) singularity encountered

 

NULL

NULL

NULL

 

Download compre1.mw

and attch back

Dear all,

I have a question: how to compute the roots of exp(z) = -1 with z in C? 

I tried: 

fsolve( exp(z) = -1, z, complex );

But it only gives one root (0.1671148658e-3+4.934802220*10^9*I) which does not even seem to be correct. I would prefere smth like z_n = I*(2*n-1)*pi or at least multiple roots...

By using

solve(exp(x) = -1, x);

it returns I*Pi.

 

MATLAB MuPAD gives the desired result:


solve(exp(x) = -1, x)

(PI*I + 2*PI*k*I, k in Z)

 

 

Thanks!

For my task I have to solve inequalities in the form

abs(z) < 1

With z being an expression yielding a complex number, but taking a real number as argument. Maple does not give any results when I pass such an expression to the function solve. It just immediately returns without any output.

 

What can I do to get the solution?

Hello

I have a complex equation EQ, it gives me 4 answers - two complex, one negative and one positive. Which assumptions do i need to use to automatically get one answer - real and positive one?

I tried similary to what I did with real equations:
simplify(solve(EQ)) assuming real, positive
But that didn't work

Is it possible to work with complex numbers in Maple T.A?

How could you for instance make a question where two complex numbers in polar form should be added. For instance (10<30deg)+(15<-10deg). I'm thinking of letting answers be in two fields, one for the absolute value and one for the angle but I would like to use random numbers in the two complex numbers to be added and would prefer to be able to use complex math in calculating the right answer.

So have to calculate frequency response of RLC-circuit
Long story short - I can't get how to solve something like this
solve(abs(I+x) = 1)
Obv - the answer is 0 or -I, but i get 1-I, -1-I instead

Hi experts,

attached the following code,, but i dont know what is the wrong with it, looking forward for helpful advise.

dsys :={diff(u(t),t)=-(N1+M*cos(2*I*omega*t))*u(t)-1+v(t)*exp(-2*I*omega*t)+w(t)*exp(2*I*omega*t), diff(v(t),t)=-(N1+I*Delta-2*M*exp(2*I*omega*t))*v(t)-(N1+u(t))*exp(2*I*omega*t)-2*M, diff(w(t),t)=-(N1-I*Delta-2*M*exp(-2*I*omega*t))*w(t)-(N1+u(t))*exp(-2*I*omega*t)-2*M}:
res:=dsolve(dsys union {u(0)=-1,v(0)=0,w(0)=0},numeric,output=listprocedure,maxfun=0):
plots[odeplot](res,[[t,(Re(w(t)))]],0..10,axes=boxed,titlefont=[SYMBOL,14],font=[1,1,18],color=black,linestyle=1,tickmarks=[3, 4],font=[1,1,14],thickness=2,titlefont=[SYMBOL,12]);
Warning, computation interrupted

how to plot ln(sqrt(x-12)/(-x^(2)+15x)

Whenever I try to plot I get 

"Warning, unable to evaluate the function to numeric values in the region; complex values were detected".

HELP PLEASE

Hi there, 

I'm trying to find a way to find the Preimage for a single point (or a small set) of a complex rational function. I've tried with the command RationalMapPreimage, which sounds like the thing to try, but I can't get my head around how this command works?

(For context, I'm trying to find the preimages of a the fixed/critical/postcritial points of a function something like f(z)=(z2-1)/(z2+1))

Many Thanks

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