Dear all

Is there any one can help me to find  the Maple code to solve these fractioanal equations  using fractional Adams-Bashforth-Moulton method

Doc229.pdf

Thank you very much for helping me.

I have the following ode: 

ode1 := diff(x(t), t, t) = (5*9.80665)*sin((1/6)*Pi)-(10*(10-sqrt(x(t)^2+25)))*x(t)/sqrt(x(t)^2+25)-(diff(x(t), t))

I tried the following code: 

DEplot(ode, x(t), t = -2 .. 2, [`$`([x(0) = (1/4)*k], k = -20 .. 20)], x = -8 .. 8, color = blue, stepsize = 0.5e-1, linecolour = red, arrows = MEDIUM)

But I get the following error: 

Error, (in DEtools/DEplot/CheckInitial) too few initial conditions: [x(0) = -5]

Any help in plotting this differential equation will be much appreciated. 

Hi,

I'm searching for an easier way to execute the following computation using only matrix calculations
(meaning no programming, no loops):

> restart:with(linalg):
> S:=matrix(3,3,[s11,s12,s13,s21,s22,s23,s31,s32,s33]):
> X:=matrix(3,1,[x1,x2,x3]):
> A:=array(1..3,1..3):
> for j from 1 to 3 do
>   for i from 1 to 3 do
>     A[i,j]:=S[i,j]/X[j,1]
>   od;
> od;
> op(A);

So far, I've got the following ideas:

A)
> S:=matrix(3,3,[s11,s12,s13,s21,s22,s23,s31,s32,s33]):
> X:=matrix(3,1,[x1,x2,x3]):
> h:=matrix(1,3,[1,1,1]):
> Xm:=evalm(transpose(h)&*transpose(X)):
## memberwise division: S / Xm   

How can I do a memberwise division?

B)
>S:=matrix(3,3,[s11,s12,s13,s21,s22,s23,s31,s32,s33]):
>X:=matrix(3,1,[x1,x2,x3]):
## make X the diagonal of a square matrix
> Xd:=matrix(3,3,[x1,0,0,0,x2,0,0,0,x3]):
> A:=evalm(S&*inverse(Xd));

How can I make a vector X the diagonal of a square matrix (without retyping the values)?

Thanks in advance
Ben

with(Physics[Vectors]);

This should  equal Dirac delta function

I know this must have been addressed somewhere previously.  However I have searched extensively and not been able to find an answer.  Sorry for asking again.

In the package Student[Calculus1], the NewTon-Cotes closed formulas are implemented. But I was thinking if there is any other package of Maple having the open Newton-Cotes Fromulas. I searched and I just saw in Student[NumericalAnalysis] for Quadratures.

I have a vector P_X

I want to use it in the constraint of Maple optimization, that all item in P_X is smaller than 1. I am looking for some expression looks like: all(P_X[i]<1,i=1..10)

Thanks.

Hello, 

I want to change some values of a matrix. 

For example: I have a matrix with measured data, but some of these values get the number 1.0 (because maple cannot import these expression correctly). Is it possible to change all "1.0" with an other expression?

Thanks a lot!
Martin

Hello there!

I am facing a strange problem. I am defining a function as a finite series which involves the constants c[k] and the variable x. when I try to calculate the value of the function at zero it should give me c[1] but its giving me 0. it seems a bug in maple. i have tried it on two different versions.i.e. 2016 and 17


Maple Worksheet - Error

Failed to load the worksheet /maplenet/convert/bug.mw .
 

Download bug.mw

The problem, find the general solution of y '' + 4y = t cos (2t).

Maple input:

de:=diff(y(t),t,t)+4*y(t)=t*cos(2*t);
sol:=dsolve(de,y(t));

Maple output:

sin(2*t)*_C2+cos(2*t)*_C1+(1/8)*t^2*sin(2*t)-(1/64)*sin(2*t)+(1/16)*t*cos(2*t)

The odd thing is the inclusion of the term -(1/64)*sin(2*t). It is not incorrect since you can collect this term with sin(2*t)*_C2. Is there a reason why it's there, and how can i remove it without inspecting it? Note that Wolfram doesn't have this extra term.

https://www.wolframalpha.com/input/?i=solve+y%27%27+%2B+4y+%3D+t*cos(2*t)

I attached the worksheet and added a more detailed calculation.

diffeq.mw

Hi,

I was wondering if anyone has a clever way to code the Cayley Omega process?
For those who are wondering, the Omega process is a differential operator. Given an n-dimensional space (x[1],x[2],x[3],...,x[n]), and n forms Q[1](x[1][1],x[1][2],x[1][3],etc) Q[2](x[2][1],x[2][2],x[2][3],etc) ... Q[n](x[n][1],x[n][1],x[n][1],etc), the operator is the determinant of the matrix who entries are the partial differential operators del/delx[i][j].

Thoughts? Suggestions?

Thanks.

The set and list produced by map (see below) contain duplicates.  How to remove duplicates?
 

Download cp.mw

 we know that  maple evaluate an expression as a tree, for example if i have the expression:

f:=x^2*exp(3/2)*sin(Pi/3-1/x);

i want to get all the tree, is there a command to obtain this !!

I get the following message:

"Error, (in Bits:-GetBits) argument 1, the number, must be a nonnegative integer"

Presumably "argument 1" does not mean that the offending argument is 1 (the problem is that the offending argument "must be a nonnegative integer", but 1 is a nonnegative integer).  So how do I get maple to report what the offending argument is? 

Could you help me to write maple code for solving following matrix differential equations?

where

In here, the matrices M,C,K,P are as follows ( M,C,K are nxn matrices and  V,P are nx1 matrices) 

In here, l,P,A,rho, alpha,v,N,E,I are constants.

Thank you very much.

I writed the matrices in maple. You can find it in the below.

 The Code.mw

I am looking to develop a histogram from a random data set that contains integers that are approximately normally distributed.  The intent is to develop a histogram from the dataset that looks like a fairly decent-approximation of a normalized curve (but not necessarily perfect)....  the next stage to this is a second histogram that shows a bimodal distribution (but not necessarily perfect)

To this point I have...

restart;

with(Statistics);

randomize();

N := RandomVariable(Normal(300, 10));

A := [seq(MapleTA:-Builtin:-decimal(0, Sample(N, 500)[i]), i = 1 .. 500)];

Histogram(A, frequencyscale = absolute, bincount = 25, binwidth = 1, tickmarks = [default, default]);

I am certain you will find what I have thus far is far from ideal, as such any help is appreciated.

Thanks,

Mark