Hi guys ;) I have a question. Is it possible to apply a PID controller with the following parameters(P=6,I=4,D=0.02)to a Non Linear System described with the differentiate equation like this mk*diff(x(t),t,t)+kfv*diff(x(t),t)-(ki^2*u(t)^2*kc)/(mk*(x(t)-x10)^2)-mk*g=0 or in the second form, as two differentiate equations like dx1 := (x1,x2) ->x2; dx2 := (x1,x2) ->((u*ki)^2*kc)/(mk*(x1-x10)^2)-g*mk/mk-kfv*x2/mk; without linearisation in operating point, where u - is input variable, x - position, dx/dt - velocity, d^2x/dt - acceleration ? Thanks for your help.

I need to generate pimitive polynomials of degree 17 over GF(2^32) for use in an LFSR working over 32-bit words. Does anyone know how it can be done?

I try to deduce distribution fonction from a parametrized set of points with Maple. At this stage I have a dataset define through a relationship like y=f(x), and I want to obtain the distribution of y points, given that x in [-A,A]. The theoretic formula is : F[Y](z) = P(y<z). i.e. F[Y](z) = Int(delta[f(x)< z],x=-A..A); and I use the piecewise Maple function to implement it ( Int(piecewise(f(x)< z,1,0),x=-A..A) ), but for Maple : Int(piecewise(f(x)< z,1,0),x=-A..A) = piecewise(Int(f(x)< z, x=-A..A),1,0)) which is totally different !

Is there a straightforward procedure to have a radical appear on the plot of a function? E.g, how can one display (2, sqrt(2)) in the plot but with the actual square-root symbol appearing. I've read in the knowledge base about the use of textplot. However, the routine is limited to exponents.

This is a program discribing the dynamic behavior of a N pendelum system. When I tried to comparae the result of different initial conditions, I found that every time i run it, the graph will be different.

I know that double pendelum system is a typical chaotic system, is this the reason why i have different result for each time?

Here I attach the file, but plz rename it to ***.mws file before run, b/c i wrote it in maple classic worksheet.

> restart:
interface(warnlevel=0):
with(SolveTools):with( plots ): with( plottools ):
with( DEtools ): with( PDEtools ):
g:=9.81:
x[0][2]:=0:
y[0][2]:=0:
#initialization function of each beam,in this function, we should give 3 variables, n=the number of this #beam, la=the length of this beam, ma=the  mass of this beam,q=the initial angle of the beam,and qt=the initial angle velocity of the beam
beams:=proc(n,la,ma,q,qt)
global l,m,x,y,theta,icq,icqt:
icq[n]:=theta[n](0)=q:
icqt[n]:=D(theta[n])(0)=qt:
l[n]:=la:           #length of  beam n
m[n]:=ma:           #mass of beam n
#initialize the positions of each beam
x[n][2]:=0:        #the x position of the end point of each beam
y[n][2]:=0:        #the x position of the end point of each beam
x[n][1]:=0:        #the y position of the center point of each beam
y[n][1]:=0:        #the y position of the center point of each beam
end proc;
#define the forces that applied on the end of  beam n
Force:=proc(n,fm,fn)
global fx,fy:
fx[n]:=fm:
fy[n]:=fn:
end proc;

has someone a sheet about percolation theory ? I put a very simple one on my blog: percolation

Is there a way to do a Symbolic Computations under Max-Plus Algebra? For instance, linear algebra computations under under Max-Plus Algebra. I would like to appreciate any comments on it.

I need to search for primitive polynomials of degree n over finite fields GF(q), where q is a PRIME POWER. I have major difficulties doing that, especially when I wish to fix one of the coefficients of the polynomial. On the other hand, polynomials over GF(p) pose no problem. Does anybody have any experience in this? PLEASE HELP!

I would like to construct a maplet to evaluate different objects in general relativity, say for example , metric,covaliant derivative and so on. Please help me with the procedure or a sample maplet.