## general case of floats not handled...

g:=Groebner:-Basis([a-2.0*b,b-2], plex);

Groebner:-Reduce(a, g, plex);

Error, (in content/polynom) general case of floats not handled

How to solve this problem simply？

## How to use Verlet algorithm to derive the orbit of...

Derive the orbit of the Moon around the Earth by doing a Verlet algorith of Molecular Dynamics simulation. Use one hour for your step τ. Place the stationary Earth at the origin of the Cartesian system. For initial conditions, use the position and the speed of the Moon when it is at its apogee (furthest from Earth). Plot the orbit.

## command "factors" doesn't work...

Why does the following not work?

factors(x^4-1)

## Maple 18 and LaTex...

Hey

As a lot of people before me I'm severely dissappointed my Maple's ability to export a .mw file to .tex.

The output looks horrible and even disappears off the side of the page in some places.

I've searched far and wide on the internet but it's difficult for me to understand the few, outdated, results I've dug up.

Is it completely impossible to get my hands on a good (or just working) Maple 18 to LaTex exporter? It's not possible for me to begin coding my own.

## plotting the result of pde system...

I have a system of pdes and solved numerically using pdsolve (numeric) command.

The system consists of four first order partial differentia equations.

for example u(x,t), R(x,t)....

what command should I give to the Maple and get the graph of u(x,t) at a specific point x_0?

For example, I need a plot for u(30,t).

Is it possible with the maple plot?

Thank you for reading this post. :)

## How do i write a code to solve a matrix in Maple?...

Write a Maple code that performs the Gaussian elimination for an nxn matrix, converting it to an upper triangular matrix.

(Hint: you will need to use three for .. do loops.)

## Translate maple code to C code...

I want to translate my maple code with matrice multiplication  to C code. But the command  "Multiply" cannot be translated. So I want to edit the function translation by myself. I use "AddFunction" command to create a new function  "Multiply" and want to specify its corresponding C code.

f := proc ()
local x,y;
x := Matrix([[1, 2], [3, 4]]);
y := Matrix([[1,3],[4,2]]);
Multiply(x, y);
NULL;
end proc;

LanguageDefinition:-Define("NewC", extend = "C", AddFunction("Multiply", [Matrix,Matrix]::Matrix,
proc (X, Y)
local a,b;
a := 2;
b := convert(a, string);
Printer:-Print("Mmultiply(", X);
Printer:-Print(",", Y, ")"); Printer:-Print("\n");
Printer:-Print("from", b, "to");
Printer:-Print(",", Y, "do") end proc, numeric = double));
Translate(f, language = "NewC")

But when I run it, the "Multiply" function cannot be translated.  The result is:

Warning, type signature [CodeGeneration:-Names:-ArrayType(integer,CodeGeneration:-Names:-ArrayRanges(1 .. 2,1 .. 2),CodeGeneration:-Names:-ArrayOptions()), CodeGeneration:-Names:-ArrayType(integer,CodeGeneration:-Names:-ArrayRanges(1 .. 2,1 .. 2),CodeGeneration:-Names:-ArrayOptions())] for function Multiply is not recognized
void f (void)
{
int x[2][2];
int y[2][2];
x[0][0] = 1;
x[0][1] = 2;
x[1][0] = 3;
x[1][1] = 4;
y[0][0] = 1;
y[0][1] = 3;
y[1][0] = 4;
y[1][1] = 2;
Multiply(x, y);
;
}

I don't know why "Multiply(x,y)" cannot be translated.

If I put two "Multiply(x, y)" in the procedure, like this:

f := proc ()
local x,y;

Multiply(x, y);
x := Matrix([[1, 2], [3, 4]]);
y := Matrix([[1,3],[4,2]]);
Multiply(x, y);
NULL;
end proc;

LanguageDefinition:-Define("NewC", extend = "C", AddFunction("Multiply", [Matrix,Matrix]::Matrix,
proc (X, Y)
local a;
a := 2;
b := convert(a, string);
Printer:-Print("Mmultiply(", X);
Printer:-Print(",", Y, ")"); Printer:-Print("\n");
Printer:-Print("from", b, "to");
Printer:-Print(",", Y, "do") end proc, numeric = double));
Translate(f, language = "NewC")

THe result is:

Warning, cannot resolve types, reassigning x's type
Warning, cannot resolve types, reassigning y's type
Error, (in CodeGeneration:-IssueError) type 'Matrix' cannot be translated to target language

I don't know why type 'Matrix' cannot be translated.

## How do I solve an ODE when I get _z1 in the soluti...

Attached is a photo with the code I am working for.

On the top is practice code with a simpler ODE to help with trouble shooting, on the bottom is the ODE I am working with.

I was hoping to gain insight about the _z1 symbol in the solution, I haven't been able to find much help on other threads.  I would like to know how I can go about working with it - if it is something on my end or if it is the nature of the equation I am working with.

Thank you for any help,

Josh

## How does one change the color/transparency of vect...

I have a nice procedure that is as follows, that explores the behaviour of a mapping in R^2.

InversePoincare := proc (v) options operator, arrow; v*Norm(v, 2)/(1-Norm(v, 2)^2) end proc

local listOfPairs;
if lengthParam = false then
return arrow(listOfPairs, scaling = constrained, shape = arrow)
else
return arrow(listOfPairs, length = lengthParam, scaling = constrained, shape = arrow)
end if
end proc

Essentially, we plot vectors v at location u. Since the vectors v in general vary wildly in magnitude, I would like to visualize the magnitude change by using color and/or transparency, preferably the latter. Is it possible to do so, and if so, how?

## on the frequent change of determinant in each run ...

Hi,

Recently a a simple problem which i can not handle by myself, made me confused.

I have simple code of maple which is not stable at all. Everytime I run the code, the final result which is the determinant of a matrix, changes and I can not see the problem with the code. In fact i noticed that problem occures when the matrix is being build by culculating the coefficients of some constant values.  I have attached the code. Could you see what is wrong here?

Thanks by the way.

## How to change page color...

hi, is there a way to change color of the page in Maple 18? in fact I am preparing my lectures using slideshow option and want to change the color instead of the default white.

## Maple nested loop error: unterminated loop...

Hi,

I'm, trying to write a nested loop in maple, but I keep getting the Unterminated Loop error. I'm sure the solution is quite simple, but I haven't been able to find it. Any suggestions would be much appreciated. The loop looks like this:

i:=0:
di:=25:
n:=1:

while (n<=nLimit) do
sol1:=fsolve(eq1, y=i..i+di)
if type(sol1, numeric) = true then
lambda(n) :=sol1
i:=i+di
n:=n+1
else  i:=i+di
end if:
end do:

## Calculate area using integration...

Hello,

please explain how to write a code to calculate and output the actual area using integration for y=X^3 over range (0,2) using left-hand rule and 200 subdivisions?

Thank you

## finding a solution of system of equation...

please is there any one can help me to find a solution of a sytem of 3 non linear equations each with 3 variable and with more than 30 unknown coefficients

this is the system

solve({EEE_x(x, y, z) = 0, EEE_y(x, y, z) = 0, EEE_z(x, y, z) = 0}, {x, y, z})

where x,y,r are the unknowns

and the three equations are simply the partial derivative with respect to x,y and z repectively

EEE_x(x,y,z):=(&DifferentialD;)/(&DifferentialD; x) EE(x,y,z)

EEE_y(x,y,z):=(&DifferentialD;)/(&DifferentialD; y) EE(x,y,z)

EEE_z(x,y,z):=(&DifferentialD;)/(&DifferentialD;z)EE(x,y,z)

the main equation is EE where (it has 3 variables and more than 30 qunknowns coefficients

(x, y, z) ->

1
----------------------------------------------------------------
2
/ 2 2 2\
hh \ii + jj x + ll z + mm y + 100. y + nn y z + oo x + pp z /

/ 2 2 2 2 3 2
\p z y + q z y + l z x + g z x + o z y + n z x + m y x

2 2 2 3 2 2 2
+ j y x + k y x + i z y + d z y + f z x + h z y

2 2 4 3 2 3
+ e y x + u z y x + v z y x + a + b x + c x + r x + s z

2 2 4 3 4 \
+ t z + bb z + cc y + dd y + ee y + ff y + gg z + aa x/

 First 10 11 12 13 14 15 16 Last Page 12 of 85
﻿