Hi:

i follow the code newton raphson for solve system nonlinear ODE in maple,every body have code for it?

I have a worksheet. I edit some variables' value. I then execute the whole worksheet to see how the graphs change. But the graphs generated by display command do not appear. All other calculations update fine. 

To overcome this. I save worksheet with my new variable values. Close the worksheet. Reopen it. Execute it. And now the graphs appear fine.

Book1.xlsHelow ,

 I want to plot a gaph the data is store in excel sheet. thanks in advance

int((1-r^3+3*r^2-3*r)(r^3-3*r^2+3*r), r = 0 .. 1);
print(`output redirected...`); # input placeholder
/ 3 2
| / 3 2 \ / 3 2 \
int\-r\r - 3 r + 3 r/ + 3 r\r - 3 r + 3 r/

\
/ 3 2 \ |
- 3 r\r - 3 r + 3 r/ + 1, r = 0 .. 1/

¿How can I substitute multiple variables with the alsub command at the same time?

For example, if I want to substitute  x=x1, y=x2, .... into the expression f=x*y+x^2+.... using just one command

Hi everyone,

Command "discont" can return the discontinuous point of the function. 

In Maple Help, it says that multiple discontinuities may be expressed with _Zn, _NNn and _Bn but just show the _Zn case and the _NNn case.

Can anyone offer the _Bn case?

Thanks!

Hi everyone,

I have a question about surface fitting. I tried to follow the step of application "Fitting an Ellipse to Data" to fit the ellipsoid surface but got the incorrect result:

It seems that the convergence condition can be modified but I have no idea. 

The related Maple file is attached:

Ellipsoid_Surface_Fitting.mw

I'd appreciate any help on this topic. Thank a lot.

Some years ago member William Fish started a long discussion in part about a numeric integral involving high parameter (high oscillation) Bessel J0. That numeric integration task appeared in a Bitwise Magazine article.

At that time even obtaining numeric results involved extra effort such as handling real and imaginary components of the integrand separately, and requesting particular methods (sometimes hacked, to bump up the subinterval limit, for very high parameter values).

That led to a post where I showed that the result could be obtained quickly by using a fast compiled BesselJ (J0) from an external library along with a modified low-level call to a particular evalf/Int solver.

And sometime after that a numeric result for the real & imaginary split integrand became much more readily (if not quickly) available by using a new `maxintervals` option of evalf/Int to specify the maximal number of subintervals for the particular solver.

Maple 18 has its own compiled implementations of the Bessel functions for "hardware" (double) precision arguments. So now the numeric evaluations of the integrand are computed much faster.

Using Maple 18.00 on 64bit Windows 7 the same numeric results obtain in under a second, in a simple, single call to evalf,Int.

restart:

CodeTools:-Usage(
  evalf(Int(BesselJ(0, 50001*x)*x*exp(I*(355*x^2*1/2)), x = .35 .. 1))
                 );
memory used=9.28MiB, alloc change=32.00MiB, cpu time=437.00ms, real time=441.00ms, gc time=0ns

                           -8                 -8  
             3.181753502 10   - 7.798301124 10   I

restart:

CodeTools:-Usage(
  evalf(Int(BesselJ(0, 10000*x)*x*exp(I*(355*x^2*1/2)), x = .35 .. 1))
                 );
memory used=6.83MiB, alloc change=32.00MiB, cpu time=218.00ms, real time=211.00ms, gc time=15.60ms

                            -7                 -7  
             -2.007752340 10   + 4.275388462 10   I

Of course the ramifications of fast, compiled Bessel functions at double precision extend much farther than just this one example. But I like seeing the speed improvement in terms of a concrete example.

acer

What is the set of the points (x,y) s. t.

y^2+y^3+(y^3-x^2-3*x*y)^(1/4) <= 5*x*y ?

How to draw it with Maple?

Using the Fourier convolution theorem to solve f(t) =sin (t)

f(t)=R dJ(t)/dt+J(t)/C

R dJ(t)/dt+J(t)/C=f(t)

where f(t) is a driving electromotive force. Use the fourier transform to analyze this equation as follows.

Find the transfer function G(alpha)  then find g(t) .

 Thanks ....

Hi , everyone who love Maple and dsolve command, 

my ODE is :

sys_ode := diff(d11(m), m) = -(3*sin(m)^2-1)*d31(m)/a^(3/2)+(-3*cos(m)*sin(m)/a^(3/2))*d41(m), diff(d21(m), m) = (-3*cos(m)*sin(m)/a^(3/2))*d31(m)-(3*cos(m)^2-1)*d41(m)/a^(3/2), diff(d31(m), m) = -a^(3/2)*d11(m), diff(d41(m), m) = -a^(3/2)*d21(m)

using " dsolve([sys_ode]) " command could get the solution easily, and the solution contains "I" (imaginary domain).

However, when we substitute the solution into the ODE "sys_ode", find not correct !

we use the following command to check the solution :

 simplify(  -diff(d11(m), m) -(3*sin(m)^2-1)*d31(m)/a^(3/2)+(-3*cos(m)*sin(m)/a^(3/2))*d41(m)  )

the upper expression is supposed to be zero, but not ! Is it a bug in Maple dsolve ?

How can I plot multiple numeric plots, such that numeric solutions belong to different differential equations?

For solving problem sets, I have a pdf template I created for myself that has a header with a blank for the class name, TA, professor, date, etc. In addition to this header, I had a margin on the left to scribble questions I had and to holepunch. 

I used to print out the template and write on the template and turn in that as my pset.

I am nowthinking of doing everything on the computer. Writing out all of the problem set on the computer. Combining stuff from maple, combining handwritten stuff from the computer using a digitizer. However I want to write it all on top of the my template that I created, which is a pdf file. I can turn the pdf into an image file if need be. 

What would be the easiest way to do what I want? To open a program that automatically sets that pdf as the template and easily lets me handwrite stuff I want and paste in maple code? 

Right now if I tried my idea, I would basically be constantly copying and pasting stuff from maple and my digitizer drawn pictures/equations into one file and it would be very clumsy.

Basically there are problems that I do partially on maple and I just want to unify all my work into one easy, printable file. 

I'm doing a pset in maple.

I paste in a block of text in maple. I put an asterik at front and end, and hit enter and it spits out an error. Why? I thought two *'s around it comment it out. 

I also can't see the file I uploaded while I preview my post.