Hello there,

Im using this code

 

> with(ExcelTools);

> L := Import("C:\parameters15.xlsx", "Sheet1", "A2:I2");

and I keep getting :     Error, (in ExcelTools:-Import) Could not open the file.

What are the possible reasons for this? I have triple checked the file name, location and extension. It's all good.

How many randomly ordered signals are required until we achieve a chaotic signal, or one that is undistinguishable from being random? Another way to put it, although not a good example, is if we had an infinitely large room full of people talking, what is the minimum number of people needed to be to make the noise appear random? Of course making a few unrealistic conditions such as the volume of each persons speech is heard at the same level and pitch no matter their distance...

readshare(gfun,analysis):
with(gfun):
orec:={y(n)+(n+1)/x*y(n+1)-y(n+2)-(n+2)/x*y(n+3)=0};
erec:=borel(orec,y(n));
edeq:=rectodiffeq(erec,y(n),Q(w));
sol := dsolve(edeq,Q(w));

Please help me out!

there is an error in using dsolve!

Error, (in dsolve/numeric/process_input) system must be entered as a set/list of expressions/equations

what can I do?

Eq17 := -3*m2*b*(diff(alpha(t), t))^2*(diff(alpha(t), t, t))*(1/2)+((-m2*b*(diff(beta(t), t, t))+2*m3*a*b*sin(beta(t))+b*sin(beta(t))*a*m2+m3*a*c*sin(beta(t)+theta(t)))*(diff(beta(t), t))+(m3*a*c*sin(beta(t)+theta(t))+m3*b*c*sin(theta(t)))*(diff(theta(t), t)))*(diff(alpha(t...

i follow a book's command

with(share):
readshare(gfun,analysis):
with(gfun):
orec:={u(n+2)+u(n+1)+u(n)=n}:
odeq:=rectodiffeq(orec,u(n),y(x)):
dsolve(odeq,y(x)):
OGF:=op(2,");

orec:={(n+4)*u(n+2)+u(n+1)-(n+1)*u(n)}:
erec:=borel(orec,u(n)):
edeq:=rectodiffeq(erec,u(n),y(x)):
dsolve(edeq,y(x)):

EGF:=op(2,");

1. all can not run with dsolve in maple 15, error expecting ode or a set or list of ode,

2. what is the meaning of op(2,");?

Hi,

I need to do this:

A:=[1,3,5,2,7];
B:=[2,5];

f(B,A)=[3,7]

Notice that the elements in A can be lists themselves. How can I define such kind of function?

TIA for the help

Hi,

I am trying to plot this function Sigma(R30) but I get failed to do so. Any one would like to try to help me out?

The attached maple sheet contains the asymptotic solution of the huge equation in .txt file. 

thx.

 20110819_doodles2.mws

20110818_section4-5a.txt

How can I plot the intersection of x^2+y^2+z^2<=9 and x^2+y^2+(z-3)^2<=9?

Is the intersection of this two equations a 3D region?

 

Thanks.

trig_integrals_prime.mw

if you put these integrals into Tool...Tutors...Calculus SV ....Integration methods, you get simpler "nicer" answers than when you integrate them directly in a worksheet (even after simplification).

why the difference?

 

I am currently attempting to write my own program in maple for the 2nd order Runge-Kutta method for a second order differential equation. What I am finding dfficlut is assigning the initial conditions.  I want to include the condition that

(d(theta)/dt)[0]=v_0 and then proceed to evaluate using different values of v_0, however I'm not allowed to assign a value to a differential.

How do I go about including this condition?

Georgie

(i^2+i*alpha+i*beta+i)*Q(n)+((-x*alpha-x*beta-2*x+beta-alpha)*n-x*alpha-x*beta-2*x+beta-alpha)*Q(n+1)+((1-x^2)*n^2+(-3*x^2+3)*n-2*x^2+2)*Q(n+2) = 0

After using diffeqtorec, there is n in coefficient, if multiply x^n/n! to all terms, i can not convert some to exponential function due to n^2, n and the difference of outer coefficient n not greater than n+2 in Q(n+2)

as i do not know the initial condition of above formula, differential equation is no use.

Hi! I need some help with a curve I'm trying to plot.

I'm asked to intersect the surface produced by f(x,y) with the plane z=1/4 and to plot the curve generated by the intersection (in 3D). I found how the curve looks like but I don´t know how to plot that in 3D.

And so with this provocative title, "pushing dsolve to its limits" I want to share some difficulties I've been having in doing just that. I'm looking at a dynamic system of 3 ODEs. The system has a continuum of stationary points along a line. For each point on the line, there exist a stable (center) manifold, also a line, such that the point may be approached from both directions. However, simulating the converging trajectory has proven difficult.

I have simulated as...

 

hi

I want to have a fprint command which should given me the data in two columns.

I want to modifiy the following command

fprintf(fd,"%f \n",li,sigmai);

this command gives me data in horizental form, i.e.,

0.001000 0.300990 0.600980 0.900970 1.200960 1.500950 1.800940  2.100930

But i want it in the follwoing form

 li              sigma

0.001000 0.300990

 0.600980 0.900970