Hello,

I want to calculate the IDs product :

hi

so ill preface this by saying my knowledge of DE equations is rusty at best and my knowledge of maple even worse so this may be a stupid question. im trying to model the dynamics of a system and when i solve for the DE equation it's giving me an accleration of zero (plotting a blank graph) when it definitely shouldnt be. ive attached the worksheet. DBM-variablemass_pro.mw

For L a given L-function (such as the Ramanujan-tau Dirichlet series) I would like to compute L(s) at 2.5*10^5 values of s equidistributed in a square region of the complex plane in a reasonably short time (meaning, say, less than an hour.) Is there a Maple function that will do this, either in the original software or available on the web?

The basic plot routine in Maple 16 has a serious problem with the domain.  The following is an example.

The domain is correct in Maple 15.  This failure occurs in both Windows 7 and Linux.

I have a rather complicated procedure to solve. All the individual parts of the program are working fine, but when I try to put them together the simulation takes too long to solve. To my knowledge what I'm trying to do is not complicated in it of itself; each system is rather simple. But the whole does not seem to be working or is simply taking way longer than expected or is impractical for the task.

I'm supposed to be doing an integration over a range of 48 (48 hours if units are of interest...

I have been generating graphics in Maple 16 using the plotsetup(ps,...) command under Windows 7 and Linux.  Maple tech support has a fix for Linux and has confirmed that there is a bug in the Windows version.  These are a Windows eps (converted to png for uploading) and png of the same figure.  The eps conversion should not do this.

For example, i have the field x*e_x+y*e_y. Is there a command for transforming it into the same field with polar coordinates and polar unit vectors?

Need help doing this asap please :).

http://imgur.com/kIvax

Hey Guys,

I'm trying to solve a system of 5 linear equations to get 5 unknowns:

> seconddegree:= proc(a,b,c) 

 if a=0 then if b=0 and c=0 then print ('infinite solutions')  

elif b=0 and c<>0 then print ('impossible')  

elif b<>0 and c<>0 then print (' one solution',x=-(c)/(b))fi;   

delta:=b^(2)-4 *a*c;    

elif if delta=0 then print('double solution',x=-b/(2 a))  

elif delta >0 then print ('exist two  solutions',x1=((-b+sqrt(delta...

Hi, i'm interested about parallel programming in maple but i cant find a good tutorial. is there anyone know a good refrence for this topic?

Hi,

I want to parallel the following code.it is good that part1 solved by one thread and part2 solved by other thread.

please help me.it must be noted that part1 and part 2 are independent "at each" iteration.

dtheta[m](x):= theta[m-1](x)+phi[m-1](x);
dphi[m](x):= theta[m-1](x)-2*phi[m-1](x);

for i from 2 by 1 to 10 do;

# part1

theta[i](x):=subs(m=i,dtheta[m](x)):
theta[i](x):=value(%):
eval(-theta[i](x),x=0);

Question :

Write a procedure that determines the solutions of a quadratic equation from inputs ,  and  by using the discriminant and the quadratic formula.

The quadratic equation procedure should be able to solve all cases: invalid input, linear case, real and complex roots. The procedure should also plot the given equation.

I dont understand how to do this can someone please please do it this for me urgently required.

today, i stuty a differential equation,  firsy, i conver the equation from cartesian to polar as  follow:

restart: 

sys := diff(x(t), t) = -y(t)+x(t)*(1-2*x(t)^2-3*y(t)^2), diff(y(t), t) = x(t)+y(t)*(1-2*x(t)^2-3*y(t)^2):

then  using transformation x=r*cos(theta),y=r*sin(theta) convert it to polar coordinate,and get:

sys1:=diff(r(t), t) = r(t)*(1-2*r(t)^2-r(t)^2*sin(theta(t))^2), diff(theta(t), t) = 1

then  plot the phase portrait, i use to method ,but all of them failed:

first ,use DEplot

  with(DEtools): 

 DEplot(sys1, [theta(t), r(t)], t = 0 .. 10, [[theta(0) = 2, r(0) = 2]], coords = polar);

and get error:
Error, (in DEtools/DEplot) can only plot in cartesian co-ordinates, got invalid option coords = polar

second,use odeplot

   with(plots):

> q1 := dsolve([diff(r(t), t) = r(t)*(1-2*r(t)^2-r(t)^2*sin(theta(t))^2), diff(theta(t), t) = 1, theta(0) = Pi, r(0) = 2], numeric, [theta(t), r(t)]);

> with(plots);

> odeplot(q1, [r(t), theta(t)], t = 0 .. 1, numpoints = 500, axiscoordinates = polar, coords = polar);

and also get a wrong result, so how to plot the phase portrait in polar coordinate using DEplot or odeplot