I have a rational function

R(s)=(s+21.2618806754099918582959684287)*(s+11.5825785765671047665686926962)*(s+2.32652929385663964079968631791)*(s+1.59184930187007023058678840475)*(s+.810126597053864402120805704729)*(s+.767936478999246633196341750975)*(s+.389728032793176474756405528288)*(s+.389709386740696868210134112440)*(s+.384534001672741409749016411776)*(s+.211738661184088496193941380283)*(s+.211735400886327624028116769728)*(s+0.123260440562617421046327062708e-1)*(s+0.749282759458414677904525855939e-2)*(s+0.129947118285955895103018704133e-2)*(s+0.128454333534479589397814117349e-2)*(s+0.342482256507583139104896521750e-3)*(s+0.342471571076865824849860353286e-3)/(s+21.2618806754099918582960530179)*(s+21.1471825573992794470615428324)*(s+2.32652929385663964079964525218)*(s+2.28350165975702233286000082419)*(s+.810126597053864402120855775248)*(s+.804997206582678244211665005890)*(s+.389728032793176474755312749208)*(s+.389718248252695846631246554139)*(s+.384534001672741409750430258543)*(s+.243633167007009257956784127718)*(s+.211735400886327624028133231990)*(s+.211726934369736929202050835884)*(s+0.749282759458414677904914554540e-2)*(s+0.555247691543530827690454070563e-2)*(s+0.128454333534479589395816020810e-2)*(s+0.126961222591792792857168643430e-2)*(s+0.342471571076865824866184397991e-3)*(s+0.342461825593204099734633561207e-3)

I want to cancell the roots which are equal up to 7 digits?

How to write a maple code for this problem?

Hi Mapleprimes community,

I am a maple novice and was trying to write a procedure but cannot tell what my syntax error is.  I would greatly appreciate if anyone can point out what I did wrong or any improvement in the code that I can make.  Thanks

SLRrepeatedsample_pr.mw

Henry

I am trying to create a procedure that can solve integrals using the Composite Simpson's 3/8 rule. However when I test my procedure against maple's ApproximateInt I am getting the wrong results.

Here is my attempt:

restart;

f:= x -> exp(x)*sin(4*x); # function I am using

simp := proc(a, b, n)
  local h, sum, i, single:
  h := (b-a)/n:
  sum := 0:
  single := (3*h/8) * (f(a) + f(b)): # this is the end points
    for i from a+h by h to b-h do
       sum := sum + (3*h/8) * (3*f(i)):
    end do:
print(evalf(sum + single));
end proc:

simp(0,1,12);
                                                                                0.6224486445
evalf(Student:-Calculus1:-ApproximateInt(f(x), 0..1, method = simpson[3/8], partition=12));

                                                                                0.5323516717

As you can see my answer is not very close to the answer given by Maple. I am not sure why my procedure simp is wrong.

If i use expression with function add() it runs normaly, but if I use expression with Threads:-Add (parallel implementation) it causes error "Error, continuation task already created for the current task" or "Kernel connection has been lost"

Expression:

Array(1 .. N,1 .. 1/2*N-NR-1,(i, m) -> evalf(Add(cosArr2[modp(k*i,N)]/kl[k],k = 1 .. NR+m-1)+Add(cosArr2[modp(k*i,N)]*alpha[k],k = NR+m .. 1/2*N)))

What am I doing wrong? Can I use two Add in one evalf?

How can I create a new object from a stanrd, defined in a given metric? For example I want to define an object by convolution of two indices of the Christoffel symbols? I cannot even to see components of such object.

Many thans for an explanation

Leonid

okay so im quite confused, im trying to write a procedure that prints the orbit of a 2x2 matrix through a given list of points.  our arguments should be a a (2x2) matrix, a list L of points represented by 2 vectors, ie (2x1) matrices and a natural number N. Returnvalue : NULL

a side effect should be to 

A^i.L[j] for i = 0 ... N and j = 1 ... nops(L)

thus, an example, if the proc is called P, then 

P(Matrix([[0,-1],[1,0]]),[Matrix([[1],[1]]),Matrix([[1],[0]])],2) 

should plot the points  

(1,1) ,(-1,1) , (-1,-1)  for the 1st point  and 

(1,0)  ,(0,1) , (-1,0) for the second

thanks for any help in advance

Composite1:=proc(g,f)
Flist := indets(f): Glist := indets(g): gof:=g:
Subslist1 := [seq( Flist[i]=q, i=1.. nops(Flist))]:
return subs(q=f,subs(Subslist1, gof)): # g(f)
end proc:
#F(g o f) = F(g) o F(f) = F o g o f = (F o g) o (F o f)
Functor := (1/2)*(-y*t2-x*t1-y*t3+sqrt(y^2*t2^2+2*y*t2*x*t1+2*y^2*t2*t3+x^2*t1^2+2*x*t1*y*t3+y^2*t3^2-4*x*t4*y*t9-4*x*t4*y*t8-4*x^2*t4*t7-4*y^2*t5*t9-4*y^2*t5*t8-4*y*t5*x*t7-4*y^2*t6*t9-4*y^2*t6*t8-4*y*t6*x*t7))/(x*t4+y*t5+y*t6);
F1:=x+2;
G1:=3*x+5;
gof:=subs(x=F1, G1);
osys := Composite1(gof, Functor) = Composite1(Composite1(G1, Functor),Composite1(F1, Functor));
sys1 := subs(x=3,subs(y=2, osys));sys2 := subs(x=5,subs(y=1, osys));
sys3 := subs(x=1,subs(y=5, osys));sys4 := subs(x=1,subs(y=2, osys));
sys5 := subs(x=2,subs(y=5, osys));sys6 := subs(x=5,subs(y=2, osys));
sys7 := subs(x=2,subs(y=1, osys));sys8 := subs(x=3,subs(y=5, osys));
sys9 := subs(x=5,subs(y=3, osys));
res:=solve([sys1, sys2, sys3, sys4, sys5, sys6, sys7, sys8, sys9], {t1,t2,t3,t4,t5,t6,t7,t8,t9});
simplify(%);
`~`[lhs](select(evalb, res));

alpha:= (1/2)*(-y*t2-x*t1-y*t3+sqrt(y^2*t2^2+2*y*t2*x*t1+2*y^2*t2*t3+x^2*t1^2+2*x*t1*y*t3+y^2*t3^2-4*x*t4*y*t9-4*x*t4*y*t8-4*x^2*t4*t7-4*y^2*t5*t9-4*y^2*t5*t8-4*y*t5*x*t7-4*y^2*t6*t9-4*y^2*t6*t8-4*y*t6*x*t7))/(x*t4+y*t5+y*t6);
g := -y/x;
f := (-x+sqrt(x^2-x*y-2*y^2))/(2*y+x);
subs(p=f,subs(q=f,subs(x=p,subs(y=q,g))));
g := (1/2)*(-x+sqrt(x^2-4*y*x-4*y^2))/(x+y);
f := x*y;
gof := subs(p=f,subs(q=f,subs(x=p,subs(y=q,g))));
lhsgofoalpha := subs(q= alpha,subs(p=alpha, subs(x=p,subs(y=q,gof))));
foalpha := subs(p= alpha,subs(q=alpha,subs(x=p,subs(y=q,f))));
rhsgofoalpha := subs(x= foalpha,subs(y= foalpha, g));
osys := lhsgofoalpha = rhsgofoalpha;
sys1 := subs(x=3,subs(y=2, osys));
sys2 := subs(x=5,subs(y=1, osys));
sys3 := subs(x=1,subs(y=5, osys));
sys4 := subs(x=1,subs(y=2, osys));
sys5 := subs(x=2,subs(y=5, osys));
sys6 := subs(x=5,subs(y=2, osys));
sys7 := subs(x=2,subs(y=1, osys));
sys8 := subs(x=3,subs(y=5, osys));
sys9 := subs(x=5,subs(y=3, osys));
res:=solve([Re(sys1)=0, Re(sys2) =0, Re(sys3) =0, Re(sys4) =0, Re(sys5) =0, Re(sys6) =0, Re(sys7) =0, Re(sys8) =0, Re(sys9) =0], {t1,t2,t3,t4,t5,t6,t7,t8,t9});

I want to taylor-expand cos(x) to the powers of two, four, and six, then to make equations which does not contain O(x^2) etc. and to obtain its value at x=0.1.

For that, I wrote as the following.
(1):
a:=seq(taylor(cos(x),x=0,i),i=[2,4,6]);
convert(a),polynom);

(2):
a:=seq(taylor(cos(x),x=0,i),i=[2,4,6]);
seq(convert(op(i,a),polynom),i=[2,4,6]);

(3):
a:=seq(taylor(cos(x),x=0,i),i=[2,4,6]):
convert(a,polynom);

All of the above were not good.

On earth, I couldn't pick up each of the result of
a:=seq(taylor(cos(x),x=0,i),i=[2,4,6])
with op(1,a).

How can I solve this problem?

I wrote the following code inside a code region in order to implement a scalar product for lists:

m:= module() option package; export `*`;
    `*`:= proc( a::list, b::list) option overload;
        return add(i, i  in zip((x, y)-> x*y, a, b));
    end proc;    
end module;
l1:=[1,2,3,4];
l2:=[4,1,0,5];
with(m);
l1*l2;

when i run the code I sometimes get the desired result ->26

but sometimes I get

I don't have any clue, where this weird behaviour comes from.

Any help would be greatly appreciated.

Hallo guys,

I am newbie in Mapple, i could not solve the problem yet, here is my little function. I want to estimate beta with the Maximum Likelihood Estimation with Weibull: 

> MaximumLikelihoodEstimate(Weibull(beta, eta), F1); F1 := Vector([1500, 1750, 2250, 4000, 4300, 5000, 7000]);
print(`output redirected...`); # input placeholder
[beta = HFloat(HFloat(undefined)), eta = HFloat(HFloat(undefined))

]

May someone help me why i just get HFloat(undefined)  ?

Kind regards

Can anyone tell me how to solve the equation above using Maple.  I know that there is a solution around x=0.995, y=0.743, but I cannot induce Maple to find it.  Any help or suggestions would be appreciated.

Ratch

Hi there,

I'm quite new to Maple so please forgive me! I have a system of partial differential equations I'm trying to solve in Maple as such below 

df/dt = f(1-f) - f * h

dg/dt = g(1-g) * Gradient(1-f * gradient(g))

dh/dt = (g - h) + Laplacian(h),

where f,g,h are functions of space and time (i.e. f(x,y,z,t)). I guess my first question is - is this possible in Maple to evaluate? (I'm currently unsure on ICs as I'm figuring it out from the model - it's a model for cancer growth I'm trying to evaluate but have a rough idea of what I'd use).

If it is possible, can you please share how I'd write this? Everytime I've tried I seem to be failing to define anything properly, so your expertise would be greatly appreciated!

Hi,

I have a problem in which i have to integrate Bessels function of first kind of order 1 from 0 to infinity. The answer that i m getting is -1, but when i am solving it numerically then the answer is close to 1. I dont know why it is happening. Please help me out for it.

Regards

Sunit