Hi, folks.

I am presently working on a computer with no math software installed and would like some help with one quartic equation:

227.0207672x^4 - 703.4677734x^3 + 845.7313843x^2 - 465.6021423x + 98.41660309 = 0

I just need numeric results.

I tried to use the online Maple Math Oracles, but they don't seem to be working right now (at least, not for me).

I have done searches for other online tools, but so many come up with different answers.

My code consists of some execution groups. There are also some Text sequencies in between.

Now I've to calculate the whole thing with some differnet values so it would be great to be able to call a loop beyond the execution groups.

That of course doesn't work.

So is there any trick to execute parts of the whole sheet several times with different values?

Hello:

I am in need of help with Maple Linearize and an exremely crypitc and most un-helpful error message. What does this mean:

> linmod := Linearize(syss, parm, linp);
Error, invalid input: Linearize uses a 4th argument, linpoint (of type {list(`=`), set(`=`)}), which is missing

I can find nothing in the help in this.

Linearize works fine when running a sample program from the help files, but fails when I run my equations.  

Hi all,

For example, I have:

restart:

with(VectorCalculus):

z1:=1+I*5;

z2:=6-I*3;

I want to plot three vectors which are represented by z1, z2 and z1+z2.

I can plot them as:

PlotVector([<Re(z1),Im(z1)>,<Re(z2),Im(z2)>,<Re(z1+z2),Im(z1+z2)>],color=[red,blue,yellow]);

But the three vectors have origin at point x:=0 and y:=0.

I can change this by applying VectorSpace as:

vs1 := VectorSpace('cartesian', [0, 0...

I've got the problem of warnings polluting my text outputs.

If I use interface(warnlevel = 0) the warnings are suppressed in the terminal but not in the files exported by the writeto command.

A sample:

> restart;with(CodeGeneration); with(plots); with(ListTools); with(FileTools);
> Matlab(u(1) = 3);
Warning, the function names {u} are not recognized in the target language
cg = u(1) == 3;
> interface(warnlevel = 0); Matlab(u(1) = 3);

I found following bug:

p := proc (k) sum((-1)^n*n/(factorial(k-n)*factorial(n)), n = 1 .. k) end proc; 

sum(p(k), k = 1 .. 1); 

sum(p(1), k = 1 .. 1); 

p(1)

Results must be same, but output is 0 (bug!), -1 (correct), -1 (correct)

can someone give help or a hint on how to overcome the faulty result in the pdsolve problem with radiation bc described in the following worksheet? I tried also with different method, but no success. the result from pdsolve makes physical no sense, because under pure radiation bc (h=0) the body should cool down and not heat up!

maple_heat_rad_pdsol.mw

thanks :-)

btw, the problem was reported befor, see:

How to compute the highest total degree of a polynomial in which a variable, say x, appears?

For example, f := x^2*y+3*x*y^2+x^3*y^3-x^5+y^4*z^5;
then the highest total degree in x is 6.

The degree command does not seem to do what I would like to do, since degree(f,x) will give 5 instead.

Thank you in advance.

Dyson_Mclean_V3.mw

Dyson_Mclean_V5.mw

Hi All,

I have a question that I see has been seldom discussed except certain posts by Mr. Lopez. This concerns the estimation of optimum parameters of the solution of a system of differential equations to fit experimental data. I referred to the Maple document provided by Mr. Lopez on the Maplesoft website.

Good morning.

I want to do a program in a worksheet that it can recall other workeet for plotting with display.

I don´t know how can recall other worksheets.

Please help me.

P.D.: I send a worksheet 01-06-2011-robot-man.mw

I'm learning to handle the output of pdsolve. It is a module and I'm quite new to that. The objective is to plot the solution for different values of, say, time t, in a fairly systematic way. I'll consign here my progress for reference. Feel free to comment if you have suggestions.

 sol := pdsolve
  ( diff(u(x, t), t) = (1/10)*(diff(u(x, t), x, x))
  , {u(0, t) = 0, u(x, 0) = 1, (D[1](u))(1, t) = 0}
  , numeric
  );

Hi,

I am tring to solve two coupled pde's with piecewise/Heaviside conditions. I am puzzled with the maple error...Rhop, Rhos are constants n given some values..

> pde_sys:=[diff(c(m,t),t)=(2/m)*diff(c(m,t),m)+diff(c(m,t),m,m)-(convert(piecewise(d(m,t)<Rhop,(Rhop-d(m,t))*d(m,t)*c(m,t)),Heaviside)+(Rhos-d(m,t))*c(m,t)*convert(piecewise(d(m,t)>Rhop,Rhop,d(m,t)),Heaviside)), diff(d(m,t),t)=convert(piecewise(d(m,t)<Rhop,(Rhop-d(m,t))*d(m,t)*c(m,t)),Heaviside...

Like when I type

1/2^2;

it gives

1/4

but if I type

0.5^2;

it gives

0.25

I want it to consider 0.5 as 1/2, because sometimes I make computations on large equations and I want to have access to the symbolic output, not the numeric output.

Hello all,

I am trying to solve a pde system with piecewise conditions numerically but unsucessful. Here's what i am doing:

> restart;

> sys:=[diff(c(x,t),t)=v(x,t)*diff(c(x,t),x$2),diff(v(x,t),t)=piecewise(c(x,t)>v(x,t),c(x,t)*diff(v(x,t),x$2),0)];

> bc:={c(0,t)=2,c(1,t)=1,c(x,0)=0,v(0,t)=1,v(1,t)=2,v(x,0)=0};

> sol:=pdsolve(sys,bc,type=numeric,time=t);

I am getting the following error.......

Error, (in pdsolve/numeric/process_PDEs...

Hello,

I am trying to solve a transient heat transfer problem.

The problem is that I have an insulated pipe that is immersed in cold water.  At time 0, the fluid filling the pipe is at a constant temperature.  The insulation at one end of the pipe is different to the rest of the insulation.  I need to find out the time that it would take any fluid to reach a certain temperature, called the cool down time.

A graphic representation of the...