if eval(simplify( subs(a=2,subs(b= 5,f))))) - n = 0 then

      hello := union(hello, {f})

end if:

after subs(a=2,subs(b= 5,f))) to verify , some of hello return -n

negative

why it is possible to pass the if condition statement?

if it is normal case, how to write correct if statement to ensure no -n 

I want to plot a cone in 3-d for any given axis vecttor, center and eccentricity.

Hello those in mapleprimes,

I have a question.

I opened Help and entered diff, for example, to have the explanation of how to use diff.

Whether it is diff or not, is not the problem I want to ask about now. But, what I want to ask is the following.

I cklicked the WS botton at the tool bar of the Help, so that I created the worksheet of the same contents of the help of the diff.

Then, I chose an expression in Calling Sequence. That is,

the first line shows

diff(f,x1, ..., xj)     on the left, and on the right \frac{d^j}{dx_j \cdots dx_I} f (I wrote this in the TeX ways, though

it is written in 2-D math input, actually)

I chose an expression on the right side, and from context menu, which appeared though right clicking of my mouse,

I selected convert to and 1-D math input, through which I changed 2-D math of the worksheet of the help file to 1-D math input.

Then, the expression shown is a strange one:

((ⅆ)^j)/(ⅆx[j] `...` ⅆx[`1`]) f;

This is still easier one. As for the third line in the Help, it has a more complicated form as

((ⅆ)^r)/(ⅆx[k]^m ⅆx[j] `...` ⅆx[3] ⅆx[2]^n ⅆx[1]^n) f;

Do you know how this way to notate is applied in maple worksheet?

Why does maplesoft use this way to notate expressions limited to the Help pages, if it is limited to the help pages.

Thanks in advance.

taro

Hello,

I use for the 3D visualization the component CAD geometry with STL files.
My STL files are created from CATIA with parts mesured in mm.
In MapleSim, in order to keep mm, I have, of course, to set "mm" in the inspector tab of the components "CAD geometry".
But, I have also to put the scale factor to 0.001.
I don't understand why I should to set it to 0.001 because :
- the CADs from CATIA are in mm.
- and the option in the inspector tab of the components "CAD geometry" is also in mm.
Would you have some precisions about the scale factor for the "CAD geometry" element ?

Thank you for your help.

I am trying to use Maple 18 to do some computations with matrices over a ring of polynomials in one variable over the integers $\mathbb{Z}[x]$, or the corresponding field of fractions $\mathbb{Q}(x)$.

The matrices in question are of dimension approximately 5000 and are sparse. The algorithm requires at least as many matrix multiplications as the dimension of the space.

Doing some small examples, of dimension 674, with a laptop (i7-3520 M CPU @2.9GHz with 8GB of Ram) gave the following disappointing result:

time(LinearAlgebra[MatrixMatrixMultiply](A,A);

34.694

When a colleague with access to a Mathematica license performed an identical calculation using sparse matrices in Mathematica, we found that Mathematica performed the calcuation in fractions of a second.

In small dimensional examples, constructing the matrices over the field of fractions as sparse in Maple 18 resulted in a four fold decrease in the already disappointing performance of the LinearAlgebra package in Maple 18.

Is there any way to improve the computational performance of Maple 18 for symbolic linear algebra? Alternatively, is the performance of Maple 2015 for symbolic linear algebra noticably better than Maple 18?

Thanks in advance.

Dave

Hello

How do I define this function? s(t) = 5*t^1/2

This function shows the pace of a particle. I have to decide the time when the pace of the particle is 2 m/s

help 

When I run a simulation (i.e. Double Pendulum Example) MapleSim crashes with no errors or dialogues - completely shuts down. The simulation seems to compile ok, then as the plots are opening it crashes. My video card driver is up to date. Anyone know how to fix this?

Thanks.

------------------------------------------------------------------------------------------------------------------------------

restart:

Digits :=30: m := 4: g :=0.3: nu := 0.4: a := 1:k:=0.2:

W:=cos(n*2*evalf(Pi)*( r-k*a)/((1-k)*a)):

ODE:=((2*(diff(W, r, r, r, r))+2*(diff(W, r, r, r))/r-4*(diff(W, r, r))/r^2+4*(diff(W, r))/r^3-(2*(1-nu))*(diff(W, r, r, r))/r+(4*(1-nu))*(diff(W, r, r))/r^2-(4*(1-nu))*(diff(W, r))/r^3)*r*(1+g*r/a)^3+(2*(2*(diff(W, r, r, r))+2*(diff(W, r, r))/r-2*(diff(W, r))/r^2-(2*(1-nu))*(diff(W, r, r))/r+(2*(1-nu))*(diff(W, r))/r^2))*(1+g*r/a)^3+(6*(2*(diff(W, r, r, r))+2*(diff(W, r, r))/r-2*(diff(W, r))/r^2-(2*(1-nu))*(diff(W, r, r))/r+(2*(1-nu))*(diff(W, r))/r^2))*r*(1+g*r/a)^2*g/a+(6*(2*(diff(W, r, r))+2*(diff(W, r))/r-(2*(1-nu))*(diff(W, r))/r))*(1+g*r/a)^2*g/a+(6*(2*(diff(W, r, r))+2*(diff(W, r))/r-(2*(1-nu))*(diff(W, r))/r))*r*(1+g*r/a)*g^2/a^2-((2*(diff(W, r, r, r)+(diff(W, r, r))/r-(diff(W, r))/r^2))/r-(2*(diff(W, r, r)+(diff(W, r))/r))/r^2-(2*(1-nu))*(diff(W, r, r, r))/r+(2*(1-nu))*(diff(W, r, r))/r^2)*r*(1+g*r/a)^3-((2*(diff(W, r, r)+(diff(W, r))/r))/r-(2*(1-nu))*(diff(W, r, r))/r)*(1+g*r/a)^3-(3*((2*(diff(W, r, r)+(diff(W, r))/r))/r-(2*(1-nu))*(diff(W, r, r))/r))*r*(1+g*r/a)^2*g/a)/(2*(diff(W, r, r))*r+2*(diff(W, r))) :

for i from 1 to m do  for j from 1 to m do
C[i,j]:=int(subs(n=i,ODE)*subs(n=j,W),r=k*a..a)
end do:end do:

Why does the collect command work for some expressions and not for others. Here is a screen shot

I assume the collect command is supposed to rewrite the expression in terms of the variable descending order.

p := expand((a^2+2*x)*(a^2+2*x));
                        4      2        2   2
                       a  + 4 a  x + 4 x

collect(p, x);
                        4      2        2   2
                       a  + 4 a  x + 4 x

Does not work.

But if you look at the screenshot , it works for other expressions.

I want to make a nested loop and store the data(with complex numbers) in matrix in order to make 3D plot.

The function hypergeom([2/3,2/3,2/3],[-1/3,4/3],z) has radius of convergence 1 and real coefficients.

But Maple tells me evalf(hypergeom([2/3, 2/3, 2/3], [-1/3, 4/3], 99/100),50);

is -138.999 + 0.0012 I
 

It should be more like −138.9962313171333091754979138344422738025

(Maple 18, version 991181)

---

G A Edgar

Hi everyone,

I would like to create an eBook with the pakage "eBookTools", but I have got several errors if in my mw document there is a table. The same error came out if I try to compile a book with the sample documents ("GettingStartedWithMaple.mw"). Anyone knows a solution?

Thank you for your time

Giorgio

My 5 year old laptop executes some commands very slowly e.g. plottools(rotate) around a line which is not a Cartesian axis. I intend to buy a new desktop. Which off-the-shelf desktops provide the fastest processing of Maple commands which do not include large data sets? Which provide the best price/performance?

Hello maple experts,

please is there any other way of solving this problem Wht.mw

Some complained that the graphs do not satisfy the boundary conditions smoothly.

Thanks.

How can I display in Maple T.A. the content of a matrix as pure text?

Thus instead of

matrix([[1, 2], [3, 4]])

1 2

3 4

Is there a solution without using Mathml and hopefully without using StringTools?

And can I assign the rectangular text display to a variable (including line feeds)?

Harry