Dear all,

I need you help to finish some steps of this idea to approximate the roots of a given equation (polynom). Thanks in advance for your help. 

I have a sturm sequence, I would like to use Bisection method to approximation the roots using Sturm decomposition of my polynom. For example, my polynom is  P=x^6-4*x^3+x-2

s := sturmseq(x^6-4*x^3+x-2,x);

sturm(s,x,-2,2); # The number of roots in the interval (-2,2)

Here, i would like to find the roots in (-M,M) :

Bounding all roots in [-M,M] where M = max{1, sum^(n-1) |ai|/an}.

f0 = f, f1 = f', then use -remainder,

I know that  sturm(s,x,-M,M); gives the number of roots in (-M,M)  but is it possible to use the variation of sign like :

      gives a Sturm sequence for f.

      variation of sign, varsign(a0,a1,...,ar).

      Thm: (Sturm) varsign(f0(alpha),...,fr(alpha)) - varsign(f0(beta),..., fr(beta))

      is the number of distinct roots of f in [alpha,beta].

then i would like Isolating roots of rational polynomials

Method: reduce, remove rational roots, divide and conquer in [-M,M],

      then use bisection  in disjoint closed intervals ctg one root each

 Bisection method :

Bisection

      Setup: f(a) < 0, f(b) > 0 (or conversely).

      Repeated subdivision of [a,b] guaranteed to get close to a root.

      Error analysis: for error eps, solve (b-a)/ 2^(n+1)  < tol for n. where tol is the tolerance

Thanks

Which of Maple commands is better for computing the radical of a polynomial f (less time of computation and less complexity)?

For example if f=x^3+3x^2y+3xy^2+y^3 then rad(f)=x+y.

in harmonic ocillator version, why it has error after it dsolve?

with(Physics[Vectors]):
with(SumTools):
Setup(mathematicalnotation = true):

Qs is Qss*cos(m*t+phi);

H := 1/(8*Pi*c^2)*Summation(Commutator(diff(Qs*cos(w*t+phi),t)*diff(conjugate(Qs*cos(w*t+phi)),t)+w^2*Qs*cos(w*t+phi)*conjugate(Qs*cos(w*t+phi))),ks=1..3)-1/c*(Summation(conjugate(Qs*cos(w*t+phi)),ks=1..3));

or

H := 1/(8*Pi*c^2)*Summation(Commutator(diff(Qs,t)*diff(conjugate(Qs),t)+w^2*Qs*conjugate(Qs)),ks=1..3);

#Qs = p, Ps := Pss*sin(m*t+phi) Ps = qs

i use

H := 1/(8*Pi*c^2)*Summation(Commutator(diff(Qs*cos(w*t+phi),t)*diff(conjugate(Qs*cos(w*t+phi)),t)+w^2*Qs*cos(w*t+phi)*conjugate(Qs*cos(w*t+phi))),ks=1..3)-1/c*(Summation(conjugate(Qs*cos(w*t+phi)),ks=1..3));

 HJ := subs(Qs= diff(f(q,P,t), q), H);

H:=subs( f(q,P,t) = f1(q) + f2(t), HJ);
sol:=dsolve({rhs(H)=E,lhs(H)=E});
S:=rhs(sol[1][1]+sol[1][2]);
p:=diff(S,q);
Q:=diff(S,E);

Hello

when i am trying to isolate for Rev in the following expression

the program doesnt respond.do you know why?

I have a vector of dimension n with each component being an equation of a linear system.

Can maple convert this Vector to a Matrix-Vector form with the matrix being constant coefficients?

Hi all.

Assume that we have partitioned [0,a], into N equidistant subintervals and in each subinterval we have M sets of poly nomials of the following form:

where T_m(t)=t^m( namely Taylor Series) and t_f is a(final point)
for Example with N=4, M=3 we have:

now we want to approximate a function, asy f(t), in this interval with following form:

Assume that we have

where '"." means common derivetive. How can we do the later integran in right way?

Note that t is unknown

Mahmood   Dadkhah

Ph.D Candidate

Applied Mathematics Department

Let B is a list of polynomial conditions such that  are none zero. Consider one polynomial f. How can I detect that f is none zero w.r.t. B? For example if B=[a-1,b+2,b-c,ac-1] and f=a^2c-ac-a+1. From B we can conclude that a<>1 and b<>2 and b<>c and ac<>1. How can I deduce that f<>0 w.r.t. B automatically?

Hi all,

I have been trying to plot Riemann Zeta Function on certain range, but it takes a lot of time(several minutes ,maybe hours).These are the basic things.

How to speed up ploting Zeta?

The same problem with Optimization.

Zeta-Problems.mw

Mathematica don't have this such problems.

Mathematica ploting Zeta with 0.125 second and optimizing 3.42 second.Maple few hours maybe......

Hello,

I want to make a for loop inside another loop, but this code does not seem to work well.

for i from 0 to 10 do

  for n from 0 to 10 do

  i+n

  end do

end do;

Regards

How would I find inflection points? I believe it would the same as if I was finding critical points for f '.

Function is:(7-x)*sin(x^2-7)

So would it be:

a:=fsolve(f2,-2.4..2.4);
b:=fsolve(f2,-2.4..-0.06);
c:=fsolve(f2,-0.06..2.4);
d:=fsolve(f2,1.49..3);
e:=fsolve(f2,-3 ..-1.52);

Plz and thanks!

Hi all,

I am a new use of Maple. I have a expression :

2.560000000*10^(-30)*k1*(2.309486127*10^38*n-1.154743064*10^38-1.186994552*10^37*k2^2*n^2+2.373989104*10^37*k2^2*n+8.541613702*10^37*k2*n^2-1.154743064*10^38*n^2+7.119519043*10^37*n^2*k1^2+6.495962587*10^37*k1*n^2-1.293058266*10^38*k2*n^2*k1-1.186994552*10^37*k2^2-1.708322740*10^38*k2*n+1.293058266*10^38*k2*n*k1+8.541613702*10^37*k2-3.529088273*10^37*k1-2.966874313*10^37*k1*n)/(1.620847396*10^9*n-1.620847396*10^9)

I want to simplify it. Obviously, it can be simplifed by simplifying the coeffecient of each terms. 

When I use 'simplify' command in Maple 18, I couldn't got what I want. 

Any suggetstions?

Thanks in advance.

Hi, 

  I have the following input

***

restart;
with( Statistics ):

a:=2;c:=0.3;
g:= exp(-a*x) + c*a*exp(-a*x);
#f := x -> piecewise( x < 0, 0, x>0, g );
 f :=x -> piecewise( x < 0, 0, x>0, exp(-a*x) + c*a*exp(-a*x));

norm_factor:=int( f(x), x=0..infinity );
print(norm_factor);

randomize():
F := Distribution( PDF = 1/norm_factor*f ):
X := RandomVariable( F ):

N := 20;
S := convert( Sample(X,N), list );

print(`cc`,S[1]);

***

The code works. However, if I comment out 

 f :=x -> piecewise( x < 0, 0, x>0, exp(-a*x) + c*a*exp(-a*x));

 , then use

f := x -> piecewise( x < 0, 0, x>0, g );

i.e.

f := x -> piecewise( x < 0, 0, x>0, g );
 #f :=x -> piecewise( x < 0, 0, x>0, exp(-a*x) + c*a*exp(-a*x));

It is said "

Error, (in Statistics:-Sample) unable to construct the envelopes for _R, try to specify the initial range"

The norm_factors are actually the same for both inputs. What is the reason for the error message?  Suppose I still want to use something like

f := x -> piecewise( x < 0, 0, x>0, g );

,how to fix the problem?

Thank you very much

I'm drawing a complete blank on this. 

The probability of a branch breaking in a particular tree as someone climbs is 2%.  After the person has climbed over 40 branches, did any of them break?  I'm trying to set that up as a simulation in Maple but I'm not sure about how to do it. 

I guess if I generate a random number and it falls under .02 it breaks, is that how I determine that?

randomize():

n := 0;
for i to 40 do
ran := evalf(rand()*10^(-12));
if ran < 0.2e-1 then n := n+1: end if:
end do:
print("Branch broke", n, "times")

I'm not sure I've got the probability right.

Shading is not valid as an option in the command defining a plottools object e.g. a parallelepiped, and yet shading can be selected in the actual display of the object. Is there a way to code for shading when creating the object?

Hi,

Ive been trying to solve critical points for maple but i keep getting this werid equation:

(1/7)*RootOf(tan(_Z)^2+4*_Z*tan(_Z)+4*_Z^2+28*tan(_Z)-140*_Z-1176)+1+(1/14)*tan(RootOf(tan(_Z)^2+4*_Z*tan(_Z)+4*_Z^2+28*tan(_Z)-140*_Z-1176)).

What I have typed

f:=x->(7-x)*sin(x^2-7);

f1:=D(f);

When I try putting:

solve(f1(x)=0);

I get that werid equation