Hello.

In maple you can use the interactive menu and choose what axes you want to look at the plot, ie. I choose Z axes and see the plot from above, can i do this by using syntax as a plot option?

Download stokes_start.mw

I have a vector x of this type:

x :=Vector[column]([A__11*u__1+A__12*u__2+...+A__1m*u__m,

A__21*u__1+A__22*u__2+...+A__2m*u__m,

...,

A__n1*u__1+A__n2*u__2+...+A__nm*u__m]);

If I define u:=Vector[column]([u__1,u__2,...,u__m]), then it is clear that the equation has the form x=A*u.

I want to extract the matrix A, for the given vectors x and u.

IMPORTANT: I know I could create a loop (i=1 to m) and set u__i=1 and all other u__j=0 (for all j not equal i) and then reconstruct each column by this method, but it seems to be a overkill for such an easy problem.

I would be glad, if someone could show me a method how one can achive this in maple.

I am trying to reproduce some systems for multibody systems by using maple.

I want to define a rotation matrix

Rot__alpha:=Matrix([[ cos(alpha) , -sin(alpha) , 0 ], [ sin(alpha) , cos(alpha) , 0 ], [ 0 , 0 , 1 ]]);

Now I want to differentiate this matrix with respect to time t. I have tried the following but it does not work:

map(implicitdiff, Rot__alpha,alpha);

I actually want something like this:

d/dt (Rot(alpha))=Matrix([[ -sin(alpha)*a , -cos(alpha)*a , 0 ], [ cos(alpha)*a , -sin(alpha)*a , 0 ], [ 0 , 0 , 0 ]]);

where a is d(alpha)/dt. So alpha is not an explicit function of t.

It would be great if someone could provide me a method for performing these kind of calculations. 
           

In C++, we use continue statement to continue with the loop. What is maple's equivalent statement of continue as used in C++?

Thanks:

Knowing that log[12](27) = a. How can I find log[36](24) in term a in Maple?

I need yours hepl.  I work with the physics paсkage and I set:

with(Physics)

Setup(mathematicalnotation = true)

 Coordinates(X)

Setup(Dgammarepresentation = standard)

Setup(spaceindices = uppercaselatin)

Define(m, m5, y, p, mm, pp)

I try to square the next value: 

W := Dgamma[mu]*d_[mu]+M+Psigma[A]*aa[A]-mm*Dgamma[0]-m5*Dgamma[0]*Dgamma[5]+I*Dgamma[5]*Psigma[B]*pp[B]+I*Dgamma[5]*y

("*" is multiplication)

W*W

And after that I want to simplify it:

Simplify(W*W)

I guess that matter is owing to d_[`~mu`]. If I remove this term:

E:=Psigma[A]*aa[A]-mm*Dgamma[0]-m5*Dgamma[0]*Dgamma[5]+I*Dgamma[5]*Psigma[B]*pp[B]+I*Dgamma[5]*y

And if i do:

E*E

Then next error emerges:

What is it?

Given 3 surfaces:

,(the xy base plane) and 

To plot these I suggested to use cylindrical coordiates knowing x=r*cos(t) and y=r*sin(t)

Which leads to 

However i got problems knowing how to plot this object and dearly ask for help.

plothelp.mw

Hi!

I am an error with the use of the function "Analytic" of the packpage RootFinding. These are the procedures:

CreaCos := proc (C, n, m, t) local k, F; F := C[1][1]+(C[1][2]-C[1][1])*t; for k to n-1 do F := F, C[k+1][1]+((1/2)*C[k+1][2]-(1/2)*C[k+1][1])*(1-cos(Pi*m^k*t)) end do; return F end proc;

Then, for k=50, 100, 150... the instruction

works correctly. However, for higher values of k (for instance, k=250) returns the below error. Some idea or suggets about occurs this error?

Many thanks for your time! 

Error, (in RootFinding:-Analytic) unable to evaluate `@`(evalf, proc (x) option remember; table( [( 0.524900000000000000000000000000e-1+Float(undefined)*I ) = Float(undefined)+Float(undefined)*I ] ) 31250*Pi*sin(62500*Pi*x)/(7/18-(1/2)*cos(62500*Pi*x)) end proc) at the value 0.524900000000000000000000000000e-1+Float(undefined)*I. The expression to be solved was probably not analytic.

Hi!

In Maple, is it possible to define an element of a series like that:

(i actually tried to enter := instead of =, but html editor told me its not valid maple expression)

So at any moment i enter  and maple give me , or  ->  ?

When transfering a particular worksheet from my home Windows 7 computer to an office Linux computer I lose some of the end of the worksheet, namely I lose a rather memory intensive animation at the end. And the office compute crashes when I attempt to run the animation. This seems strange since apparently the office computer (see below) is more powerful than my home computer.  When this happens there are apparently few if any other users of the office computer. I  would be grateful for suggestions for remedies for this problem or any ideas of what the problem could be.

Home computer: Windows 7 Intel(R) Core(TM) i7-2600 CPU@3.40GHz, 12 GB RAM 64-bit OS

Office computer: CentOS, Kernel Linux 2.6.32-573.12.1.l6.x86.64, Gnome 2.28.2, Memory 94.4GiB, 6 processors each an Intel(R) Xeon(R) CPU E5-2643 v2@3.5BHz, Available Disk Space 1061.0 BiB

I have solved a BVP using finite difference method in maple. But the comparsion with the dsolve solution shows big difference,

Why there is too much difference? Is there an elegant way to implement FDM?

FDM_Dbvp_sheet_1.mw

i wrote a procedure for determine a lambda symmetries and first integrals of ODEs.

Procedure is running but commands is getting error.

Can  anybody help me.

Thanks in advance. procedure.mws

If a particle that moves in only one dimension is subject to a force Fi between the time

steps ti and ti+1, the velocity vi and position xi of the particle is:

v[i] := v[i − 1] +(1/m)*F[i]*Δt

x[i] := x[i − 1] + 0.5 (v[i − 1] + v[i])                   

Use the mean of v between ti and ti+1 when updating xi, since the value may change

a lot from step to step. In the subsequent, we set the mass m = 1 and the time steps

are Δt = 1, since we could absorb m and Δt in the expression for the force Fi anyway.

Write a procedure that computes xi and vi for a particle subject to random forces Fi,

uniformly distributed on the interval [-0.5..0.5].

I`ve written a procedure that generates random forces (F[i]) in the given interval. How can I write a for – procedure that computes x_i and v_i ?

For exaqmple, the quadratic equation w^2 + uw + v = 0 corresponds to the deter minant

| -u  1  1  |

| v    0  1  |  = 0

|w^2 w w-1|

Is there any way to find a determinant corresponding to an equation, as above?

This is an issue in the preparation of a nomograph for the initial equation.  

It is generally solved by trial and error.

hi

i want save result in text file?

how i can do it?

for example eta and F(eta) in two  column

sample file is attache.

printf.mw

txtop1.txt

sample for save results::::

eta                     F(eta)

0.00000000, 0.00000000
0.10000000, 0.00096663
0.20000000, 0.00373543
0.30000000, 0.00810907
0.40000000, 0.01388926
0.50000000, 0.02087683
0.60000000, 0.02887169
0.70000000, 0.03767307
0.80000000, 0.04707963
0.90000000, 0.05688968
1.00000000, 0.06690139

Download txtop1.txt