i recall having asked this question before and having received answers which unfortunately I cannot locate.

I wish to generate a sequence like
    a[1], b[1], a[2], b[2], a[3], b[3]

The following does not work for the obvious reason:

    seq(a[i], b[i], i=1..3);

What is the right way?

Let a piecewise-linear curve be defined by a listlist. For example,

LL := [[1.1, 2.04], [1.97, 4.04], [2.96, 2.97], [4.5, 6.4], [5.08, 7.21], [1.1, 4.04], [1.1, 2.04]]:
plot(LL);

How to find its natural parametrization in Maple? A procedure is desired. See Wiki for info.

Hi everyone.

I have been experiencing a problem trying to solve a coupled system of 3 differencial equations

My problem is that a got a message back as I try to solve the system:

"Error, (in pdsolve/numeric/process_IBCs) improper op or subscript selector"

by apply this point that ''all dependent variables must be functions of the same independent variables''

i again accost with another error ''

Error, (in pdsolve/numeric/process_IBCs) initial/boundary conditions can only contain derivatives which are normal to the boundary, got (D[1, 1](w))(x, -3/400000000)

''

please help me.....very very thanks

Hello people in mapleprimes,

I have a question about why what is shown by maple by simplify(-8)^(1/3) is 1+ Complex(1)* (3)^(1/2)?

Solutions of x^3=-8 are -2, 1+Complex(1)*(3)^(1/2) and 1- Complex(1)*(3)^(1/2). And, as for the last one, 1- Complex(1)*(3)^(1/2), it is 

the conjugate of the second, so it might not need to be written, because of it being easily seen so.

Is it the same reason why just -2 is not shown as the result of simplify((-8)^(1/3))?

PS. I know the instruction to use surd in such a case.

the reason I asked this question is this:

I am reading Essential Maple, where

ln(z) = ln(rho*exp(Complex(1)*theta));

ln(rho*exp(Complex(1)*theta))=ln(rho)+Complex(1)*theta;

ln(rho)+Complex(1)*theta;=ln(rho)+Complex(1)*arctan(y,x);

and

z^a=exp(a*ln(z));

and

"Because of

exp(w*Pi*Complex(1)*k)=cos(2*Pi*k) + Complex(1)*sin(2*Pi*k);

and

cos(2*Pi*k) + Complex(1)*sin(2*Pi*k)=1;

we could equally well have chosen

ln_k z = ln(z) + 2*Pi*Complex(1)*k"

are written.

 Supposing these, there is a sentence that

"we choose k=0, and thus -Pi<=theta<=Pi to be the one (that for our canonical logarithm).

Every computer algebra language and numerical language follows this standard and takes the

complex logarithm to have its imaginary part in this range.

With this definition, (-8)^(1/3)=1 + Complex(1)*sqrt(3), and not -2. (the end of quotation)"

And, I can't understand the last sentence"With this definition", so I asked the above question.

I hope someone give an answer to the above question.

Thanks in advance.

taro

Dear all

i want to plot this equation can someone help me

v=beta^(-1)(f/2)

beta=(t^(0.5);1/5,1/2)

beta is beta function i want to plot v wrt f

thanks

Hello!

I defined a line normally, but when I try plot this line in R3, appears a shape of a plane.

How can I plot only a line in a 3D window?

Line has coordinates x,y, e z.

I wish to display the following screen output from a procedure A(), in a textbox of mathcontainer or any other suitable component.

This output to screen listing is generated by print statements in the procedure A().

I have placed the procedure call A() in a textbox and then am using a button component to execute it with the objective of displaying the above output in another component display box; either a textbox or a MathContainer box...  I can see that A() executes, but do not know how to get the result to display in a component box.

Can anyone offer any help?

hi.may  help me for solve this nonlinear equations by numeric solver maple39.d39.pdfocx39.pdf

thanks alot

file format is pdf and word type

and show whether there is sink or source?

ode1:=a(t)*(diff(a(t), t))+c(t)*(diff(c(t), t))=3*t;
ode2:=a(t)*(diff(a(t), t))+a(t)*(diff(a(t), t))*b(t)*(diff(b(t), t))*c(t)*(diff(c(t), t))=3*t;
ode3:=a(t)*(diff(a(t), t))+a(t)*(diff(a(t), t))*c(t)*(diff(c(t), t))+a(t)*(diff(a(t), t))*b(t)*(diff(b(t), t))*c(t)*(diff(c(t), t))=2*t;

DEtools[DEplot3d]({ode1,ode2,ode3},[a(t),b(t),c(t)],t=0.5..1.4,a=0..1.4,b=0..1.4,c=0..1.4,[[a(1)=1,b(1)=2,c(1)=3]],scene=[a(t),b(t),c(t)], arrows=medium);

unable to convert to explicit first order system, do not understand this error message

Hi!!

I'm trying to define a function by a definite integral. For this, first we define the following  procedure

and the map

So, for a given m, my desired  "function" should be fun(curva(m,t)). The problem here, is that this function not work because, for instance, for m=2 the command fun(curva(2,t)) returns the below expession, which i think is wrong (where is the expression on "sin" or "cos(2*Pi*t)" ???)

Somebody can help me??

Thanks!!!

Hello!

Is it possible convert some equations in R² (ellipse, hyperbola) to polar coordinates using Maple? And a regular  object in R³ like a sphere, a cylinder or a cube could be converted from cartesian coordinates to polar coordinates?

Thank you so much.

Hi everybody,

i'm trying to do an elliptic regularization but i don't know how to proceed ?

Is someone know how to achieve to do that  with an example ?

thanks a lot !

PS: i know only how to do a linear regularisation.

I am considering the following PDE and I am getting an error, please suggest a better numerical method than the default one used in maple:

the PDE is:

u_{xx}u^3 - sin(xt)u_{tt} = u(x,t)

u(x, 0) = sin(x), (D[2](u))(x, 0) = cos(x), u(0, t) = cos(t), (D[1](u))(0, t) = sin(t)

Please suggest me a method that will also work for the following PDEs:

u^m* u_{xx} - sin(xt)u_{tt} = u^n

for m,n =0,1,2,3,... for the cases m=n and m not equal n

Here's the code:

Download nonlinear_hyperbolic_PDE.mw

Hi,

I'm trying to compile a worksheet and save it on Mac OSX. The worksheet ends with this code:

>

> save `E:\\class work\\THERMODYNAMICS\\ThermoSoft\\Compiled\\SteamTables.m`;

>

The guide tells me to change the path to a user specified folder where the .m file will be saved.

Since the path name already given is a Windows path, I have to change that to a Mac path.

My problem is, that i don't know what I should write?

I have tried writing:

save `\\Macintosh HD\\Users\\Name\\Folder\\SteamTables.m`;

But it gives an error, and can't save the file. 

eq1 := a(t)*(diff(a(t), t))+a(t)*(diff(a(t), t))*b(t)*(diff(b(t), t))*c(t)*(diff(c(t), t));
eq2 := a(t)*(diff(a(t), t))+a(t)*(diff(a(t), t))*c(t)*(diff(c(t), t))+a(t)*(diff(a(t), t))*b(t)*(diff(b(t), t))*c(t)*(diff(c(t), t));

DEplot({eq1, eq2}, [b(t), c(t)], t = 0 .. 1, b = 0 .. 1, c = 0 .. 1, [[b(0) = 1, c(0) = 1]], arrows = large);

Error, (in DEtools/DEplot/CheckDE) only derivatives of dependent variables can be present

DEplot({eq1 = 3*t^2, eq2 = 2*t^3}, [b(t), c(t)], t = 0 .. 1, b = 0 .. 1, c = 0 .. 1, [[b(0) = 1, c(0) = 1]], arrows = large);
Error, (in DEtools/DEplot/CheckDE) only derivatives of dependent variables can be present