Maple Questions and Posts

These are Posts and Questions associated with the product, Maple

Hello everybody,

While i was trying to work on a physical math problem, a system of 4 integral equations is obtained. The right hand sides of these equations are known functions of r. The left hand sides contain double integrals with respect to lambda and t. i believe that an analytical determination of the 4 unknown functions f_1(t), f_2(t), f_3(t), and f_4(t) is far from being trivial, thus recourse to a numerical technique is necessary and indispensable.

 

i tried to express the unknown functions as series expansions in t and solve the resulting linear system of equations for the expansion coefficients, but unfortunately the coefficients are very large and the solution is strongly dependent on the number of coefficients. i was wondering whether someone here has some experience with such integral problems and is willing to assist and help. Any hint is highly appreciated.

 

i attach a Maple script including the equations.

Thank you,

 

>>>>>> Question.mw

I am trying to use Maple to solve a set of 5 equations, but cannot get a solution. Or there is no solution??

Any help? (Yes, the L function is a likelihood function and I am doing MLE for 5 variables..)


 

``

h := 4

4

(1)

k := Matrix(3, 4, {(1, 1) = 11.0, (1, 2) = 7.0, (1, 3) = 7.0, (1, 4) = 11.0, (2, 1) = 5.0, (2, 2) = 7.0, (2, 3) = 12.0, (2, 4) = 12.0, (3, 1) = 1., (3, 2) = 9.0, (3, 3) = 7.0, (3, 4) = 19.0})

Matrix(%id = 18446746279852723246)

(2)

A := Vector[row](3, {(1) = 6.0, (2) = 13.0, (3) = 18.0})

Vector[row](%id = 18446746279852713854)

(3)

B := Vector[row](3, {(1) = 3.0, (2) = 4.0, (3) = 4.0})

Vector[row](%id = 18446746279852763126)

(4)

"l(N1,M1,lambda,phi,r):=product((phi*(N1-'B[i]'+r*'A[i]'))^('k[i][1]')*(1/(2)*lambda*(M1-'A[i]'))^('k[i][2]'+'k[i][3]')*(1-phi*(N1-'B[i]'+r*'A[i]')-lambda*(M1-'A[i]'))^('k[i][4]')   ,i=1..(h-1))"

proc (N1, M1, lambda, phi, r) options operator, arrow, function_assign; product((phi*(N1-'B[i]'+r*'A[i]'))^'k[i][1]'*((1/2)*lambda*(M1-'A[i]'))^('k[i][2]'+'k[i][3]')*(1-phi*(N1-'B[i]'+r*'A[i]')-lambda*(M1-'A[i]'))^'k[i][4]', i = 1 .. h-1) end proc

(5)

``

``

NULL

fsolve({diff(ln(l(N1, M1, lambda, phi, r)), M1) = 0, diff(ln(l(N1, M1, lambda, phi, r)), N1) = 0, diff(ln(l(N1, M1, lambda, phi, r)), lambda) = 0, diff(ln(l(N1, M1, lambda, phi, r)), phi) = 0, diff(ln(l(N1, M1, lambda, phi, r)), r) = 0}, {M1, N1, lambda, phi, r}, N1 = 0 .. infinity, M1 = 0 .. infinity, lambda = 0 .. 1, phi = 0 .. 1, r = 0 .. 1)

``


 

Download PlayGround.mw

I would like to find a fixed point of f^4 in tems of a and b. I define function as

 

I calculate f(f(f(f(x,y))))  and Iet f(f(f(f(x,y)))) = (x,y), then use the solve command as:

solve({b^4*(a*(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)-(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)^2-(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)*b^2*(a*x-x^2-x*y)*x*y)*(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)*(a*x-x^2-x*y)*x*y = y, a*(a*(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)-(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)^2-(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)*b^2*(a*x-x^2-x*y)*x*y)-(a*(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)-(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)^2-(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)*b^2*(a*x-x^2-x*y)*x*y)^2-(a*(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)-(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)^2-(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)*b^2*(a*x-x^2-x*y)*x*y)*b^3*(a*(a*x-x^2-x*y)-(a*x-x^2-x*y)^2-(a*x-x^2-x*y)*b*x*y)*(a*x-x^2-x*y)*x*y = x}, {x, y})

My computer was freezing. How can I get my result. Thank you

 

Hi guys, 

I have tried to create a loop to solve a set of two equations, but can't seem to get it working. My initial equations are given by;

 

nstar := (F, L, sigma) -> ceil((ln(k*F) - ln(c(L, sigma)*B))/ln(Phi(L, sigma)))

 

and 

 

i := (F, L, sigma) -> r*(1 - (G(L, sigma)*Phi(L, sigma))^nstar(F, L, sigma)*B/F)/(1 - G(L, sigma)^nstar(F, L, sigma))

 

in which both are based on further rather simple equations. To these I am trying to apply the proc function where I am trying to find which i makes borth the equations above work :

 

i := proc(F,L,sigma)  

local k :=0.01 ;  

local eps := 0.01 ;  

do while(eps>0.001)  

nstar:= (6)

i := (7)

eps:= i -k:

k=i:

end do;

k;

end proc;


Error, Got internal error in Typesetting:-Parse : "'_Inert_DELAYLESSTHAN' is not a valid inert form"
 

But as you see I am here getting a error which I have not managed to fix. Can anyone see where I might have gone wrong? Could this be done by solve or fsolve? If yes, then how (have tried it as well without succeding)?

help me! 

 

I have a problem with the system, looking forward to everyone's help!

Hello!

How can I make MAPLE to create the solution of the following system?

https://math.stackexchange.com/questions/301068/how-do-you-find-a-corresponding-recurrence-relation-for-some-random-algorithm/301709

according to this link, how to parse or walk through the algorithm in maple to generate recurrence relation formula?

I have a differential equation involving several functions of the following form:

diff(h,z) = iAf + iBg,

where h, f and g are functions of the Cartesian coordinates x, y and R and the third coordinate corresponds to z = R for some fixed constant value R.  The derivative is then with respect to the coordinate z and A and B are constants, with i the usual imaginary unit.  Is there some way this equation could be solved explicitly with Maple?

Basically it spits out the subset of values for which a division by zero error will occur for the function you specify on  range you specify for each of it's arguments, but I get an ambigous error when ever exponentiation features in the function I specify, which of course dramatically reduces the application of the calculator. Division,addition,substraction and multiplication are currently the only available arithmetic operators availble for the function window that I know the error will not occur.

If some one can help it is much appriciated

 

DIVISION_BY_ZERO_CALCULATOR.mw

hello everyone,
   INGT.mw
 

L__d := 100:

L__b := 200:

L__c := L__d+(1/2)*L__b;

200

(1)

X := .3;

.3

(2)

Error, (in plot) procedure expected, as range contains no plotting variable

 

`ΔE__g` := 1.155*X+.37*X^2;

.3798

(3)

V__0 := .6*`ΔE__g`;

.22788

(4)

m__D := 0.67e-1*m[e];

0.67e-1*m[e]

(5)

m__B := (0.67e-1+0.83e-1*X)*m[e];

0.919e-1*m[e]

(6)

Sol := solve(2*cos(L__d*sqrt(E__x))+(m__D*sqrt((V__0-E__x)/E__x)/m__B-m__B*sqrt(E__x/(V__0-E__x))/m__D)*sin(L__d*sqrt(E__x))-(m__D*sqrt((V__0-E__x)/E__x)/m__B+m__B*sqrt(E__x/(V__0-E__x))/m__D)*sin(L__d*sqrt(E__x))*exp(-sqrt(V__0-E__x)*L__b) = 0, E__x);

0.1110897170e-2, 0.3531161505e-2, -.2585338615+0.9991335677e-27*I

(7)

 

0.1110897170e-2, 0.3531161505e-2, -.2585338615+0.9991335677e-27*I

(8)

E__1 := 0.1110897170e-2:

K__1 := sqrt(E__1);

0.3333012406e-1

(9)

K__2 := sqrt(V__0-E__1);

.4762027959

(10)

C := cosh((1/2)*K__2*L__b);

0.2399908351e21

(11)

beta := m__D*K__2/(m__B*K__1);

10.41631973

(12)

B := -beta*sinh((1/2)*K__2*L__b);

-0.2499821271e22

(13)

A := -B*sin(K__1*L__d)+C*cos(K__1*L__d);

-0.7112056933e21

(14)

h := proc (x) options operator, arrow; piecewise(x <= -L__c, A*exp(K__2*(x+L__c)), -L__c < x and x < -(1/2)*L__b, -B*sin(K__1*(x+(1/2)*L__b))+C*cos(K__1*(x+(1/2)*L__b)), abs(x) <= (1/2)*L__b, (1/2)*exp(K__2*x)+(1/2)*exp(-K__2*x), (1/2)*L__b < x and x < L__c, -B*sin(K__1*(x-(1/2)*L__b))+C*cos(K__1*(x-(1/2)*L__b)), L__c <= x, A*exp(K__2*(x-L__c))) end proc:

'h(x)' = h(x);

h(x) = piecewise(x <= -200, -7.112056933*10^20*exp(95.24055918+.4762027959*x), -200 < x and x < -100, 2.499821271*10^21*sin(3.333012406+0.3333012406e-1*x)+2.399908351*10^20*cos(3.333012406+0.3333012406e-1*x), abs(x) <= 100, (1/2)*exp(.4762027959*x)+(1/2)*exp(-.4762027959*x), 100 < x and x < 200, 2.499821271*10^21*sin(0.3333012406e-1*x-3.333012406)+2.399908351*10^20*cos(0.3333012406e-1*x-3.333012406), 200 <= x, -7.112056933*10^20*exp(-95.24055918+.4762027959*x))

(15)

L__y := 200:

L__z := 200:

P := proc (x, y, z) options operator, arrow; h(x)*cos(Pi*y/L__y)*cos(Pi*z/L__z) end proc:

'Psi(x, y, z)' = P(x, y, z);

Psi(x, y, z) = piecewise(x <= -200, -7.112056933*10^20*exp(95.24055918+.4762027959*x), -200 < x and x < -100, 2.499821271*10^21*sin(3.333012406+0.3333012406e-1*x)+2.399908351*10^20*cos(3.333012406+0.3333012406e-1*x), abs(x) <= 100, (1/2)*exp(.4762027959*x)+(1/2)*exp(-.4762027959*x), 100 < x and x < 200, 2.499821271*10^21*sin(0.3333012406e-1*x-3.333012406)+2.399908351*10^20*cos(0.3333012406e-1*x-3.333012406), 200 <= x, -7.112056933*10^20*exp(-95.24055918+.4762027959*x))*cos((1/200)*Pi*y)*cos((1/200)*Pi*z)

(16)

INGT := proc (x__i) `assuming`([evalf(int(int(int(P(x, y, z)^2*exp(-lambda*sqrt((x-x__i)^2+y^2+z^2)), x = -infinity .. infinity), y = -L__y .. L__y), z = -L__z .. L__z))], [0 < lambda]) end proc

evalf(INGT(2))

``

Warning,  computation interrupted

 

``


 

Download INGT.mw
 

L__d := 100:

L__b := 200:

L__c := L__d+(1/2)*L__b;

200

(1)

X := .3;

.3

(2)

Error, (in plot) procedure expected, as range contains no plotting variable

 

`&Delta;E__g` := 1.155*X+.37*X^2;

.3798

(3)

V__0 := .6*`&Delta;E__g`;

.22788

(4)

m__D := 0.67e-1*m[e];

0.67e-1*m[e]

(5)

m__B := (0.67e-1+0.83e-1*X)*m[e];

0.919e-1*m[e]

(6)

Sol := solve(2*cos(L__d*sqrt(E__x))+(m__D*sqrt((V__0-E__x)/E__x)/m__B-m__B*sqrt(E__x/(V__0-E__x))/m__D)*sin(L__d*sqrt(E__x))-(m__D*sqrt((V__0-E__x)/E__x)/m__B+m__B*sqrt(E__x/(V__0-E__x))/m__D)*sin(L__d*sqrt(E__x))*exp(-sqrt(V__0-E__x)*L__b) = 0, E__x);

0.1110897170e-2, 0.3531161505e-2, -.2585338615+0.9991335677e-27*I

(7)

 

0.1110897170e-2, 0.3531161505e-2, -.2585338615+0.9991335677e-27*I

(8)

E__1 := 0.1110897170e-2:

K__1 := sqrt(E__1);

0.3333012406e-1

(9)

K__2 := sqrt(V__0-E__1);

.4762027959

(10)

C := cosh((1/2)*K__2*L__b);

0.2399908351e21

(11)

beta := m__D*K__2/(m__B*K__1);

10.41631973

(12)

B := -beta*sinh((1/2)*K__2*L__b);

-0.2499821271e22

(13)

A := -B*sin(K__1*L__d)+C*cos(K__1*L__d);

-0.7112056933e21

(14)

h := proc (x) options operator, arrow; piecewise(x <= -L__c, A*exp(K__2*(x+L__c)), -L__c < x and x < -(1/2)*L__b, -B*sin(K__1*(x+(1/2)*L__b))+C*cos(K__1*(x+(1/2)*L__b)), abs(x) <= (1/2)*L__b, (1/2)*exp(K__2*x)+(1/2)*exp(-K__2*x), (1/2)*L__b < x and x < L__c, -B*sin(K__1*(x-(1/2)*L__b))+C*cos(K__1*(x-(1/2)*L__b)), L__c <= x, A*exp(K__2*(x-L__c))) end proc:

'h(x)' = h(x);

h(x) = piecewise(x <= -200, -7.112056933*10^20*exp(95.24055918+.4762027959*x), -200 < x and x < -100, 2.499821271*10^21*sin(3.333012406+0.3333012406e-1*x)+2.399908351*10^20*cos(3.333012406+0.3333012406e-1*x), abs(x) <= 100, (1/2)*exp(.4762027959*x)+(1/2)*exp(-.4762027959*x), 100 < x and x < 200, 2.499821271*10^21*sin(0.3333012406e-1*x-3.333012406)+2.399908351*10^20*cos(0.3333012406e-1*x-3.333012406), 200 <= x, -7.112056933*10^20*exp(-95.24055918+.4762027959*x))

(15)

L__y := 200:

L__z := 200:

P := proc (x, y, z) options operator, arrow; h(x)*cos(Pi*y/L__y)*cos(Pi*z/L__z) end proc:

'Psi(x, y, z)' = P(x, y, z);

Psi(x, y, z) = piecewise(x <= -200, -7.112056933*10^20*exp(95.24055918+.4762027959*x), -200 < x and x < -100, 2.499821271*10^21*sin(3.333012406+0.3333012406e-1*x)+2.399908351*10^20*cos(3.333012406+0.3333012406e-1*x), abs(x) <= 100, (1/2)*exp(.4762027959*x)+(1/2)*exp(-.4762027959*x), 100 < x and x < 200, 2.499821271*10^21*sin(0.3333012406e-1*x-3.333012406)+2.399908351*10^20*cos(0.3333012406e-1*x-3.333012406), 200 <= x, -7.112056933*10^20*exp(-95.24055918+.4762027959*x))*cos((1/200)*Pi*y)*cos((1/200)*Pi*z)

(16)

INGT := proc (x__i) `assuming`([evalf(int(int(int(P(x, y, z)^2*exp(-lambda*sqrt((x-x__i)^2+y^2+z^2)), x = -infinity .. infinity), y = -L__y .. L__y), z = -L__z .. L__z))], [0 < lambda]) end proc

evalf(INGT(2))

``

Warning,  computation interrupted

 

``


 

Download INGT.mw

 

I'm trying to calculate a triple integral complicated by a procedure that changes each time a variable xi, while the program takes a lot of time and it gives me the message "Warning, computation interrupted". If anyone can help me I will be very happy

Is there something I should be doing whenever I use simplify to avoid things like this, or should I stop using the "is" function all together?

 

interface(showassumed = 0):

 

sum(binomial(k+j, k), j = 0 .. n-k) = binomial(n+1, k+1)

(n-k+1)*binomial(n+1, k)/(k+1) = binomial(n+1, k+1)

(1)

#And we have:
is(sum(binomial(k+j, k), j = 0 .. n-k) = binomial(n+1, k+1))

FAIL

(2)

#And since:
is(simplify(convert(sum(binomial(k+j, k), j = 0 .. n-k) = binomial(n+1, k+1), 'factorial')))

true

(3)

is(sum(binomial(k+j, k), j = 0 .. n-k) = binomial(n+1, k+1)) = is(simplify(convert(sum(binomial(k+j, k), j = 0 .. n-k) = binomial(n+1, k+1), 'factorial')))


 

Download main.mw

Hello people :) 

As the captian says, im trying to remove an old task i've made.
But i get this:

Error in Get, invalid object [_XML_reply_data_get("reference" =
"_Maplets_reference_12","parameter" =
"value",_XML_content("Task,UserTasks,Nyops",&Entity "#xc3",&Enity
"#xa6","tning"))]

And i have no idea what it is, but it won't erase my task :'D

Thanks a bunch in advance! 

Have a great weekend you all
Best regards Lucas :)

A few seconds after calling up Help starts zucking araound and the whole computer then freezes. Ctrl-Alt-Delete doesn't work, hard reset required. Very funny. Am I alone?

Hi good afternoon , im looking for maple code of HPM to solve time dependent diffusion reaction , can anybody help me . I didnt get how to solve it by maple . 

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