MaplePrimes Questions

Search Questions:

Latest Questions Latest Questions Feed

I’m trying to use Maple to develop tensor operations using the epsilon-delta notation as used in the attached document, which makes use of the following relationships

permutations.pdf    epsilondelta.pdf

I see how to generate permutations in Maple, and I see there is some mention of what I am trying to do in Maples definition of a signature.  But I am unable to see how to implement it.  Does anyone have any ideas?

Collatz := proc (n)

    local count;

       while n != 1 do

           if `mod`(n, 2) = 0 then n := (1/2)*n

           else n := 3*n+1

           end if;

           count := count+1;

       end do;


end proc:


I wanna correct 'illegal use of formal parameter' error.

'n' always goes to 1 through 'while statement'.

though swap can do this,

hope to know a simple way to shift a list or set to the left in cycle in maple

for example





I am trying to use Apollonius procedure from geometry package. Here is an example:

circle( c1, [ point( c1c, 0 , 0 ), 5 ] );
circle( c2, [ point( c2c, 5 , 4 ), 2 ] );
circle( c3, [ point( c3c, 13 , 0 ), 3 ] );
A := Apollonius( c1, c2, c3 );

Unfortunatelly the Apollonius method does not give any result. The only message is:

intersection: there is no point of intersection


Anyone know what is wrong in my code?

Best regards

Rafał Nowak

about the help menu of maple2015

I cannot find the help-manual menu at th maple2015

but I can find it at maple18.

how can I use the help-manuals..-List of Packages  from maple2015?




The black point correction for xyY to sRGB was incorrect in my original post. It should be done the same ways as for xyY to aRGB which was correct. Hope nobody was inconvenienced. 


I would be curious if others have found a more elegant way to index through an Array to perform an operation on a set of vectors. I had to use the single quote to get the operation performed first and the index increment second. 

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?


Dear Maple users

An engineering student asked me how Maple is handling complex numbers in polar form. He told me that his fellow students are using another CAS, whereas he himself prefer Maple. When making calculations with AC currents having different phases the other students were using the easy notation depicted in the first line on the picture below. Obviously here the angle (argument) is measured in degrees. I tried to perform the same calculations in Maple, but found it to require a very heavy notation: the other three lines on the picture. Now my question is: Does it really have to be that messy, or maybe there are some package, which will accomplish the task in a more neat way? I mean it is a rather common operation in the engineering sciences.

NB! Of couse one can argue about the educational value of using the notation of the other CAS! From that viewpoint they will probably not learn anything ...






Can Maple compare irrational numbers?

A simple command like   if(2<√5,0,1)   is not working for me. 


  If I use




I got 



This result holds if ab=ba. Otherwise the result is a^2 + ab + ba + b^2


Is there any simpler way to obtain  a^2 + ab + ba + b^2? I looked up

but did not find a solution :(


Thank you very much!




How to simplify this result in order it returns the correct answer i.e : sqrt(Pi)/2*exp(-2*abs(x))  -infinity<x<infinity.

int(exp(-t^2-x^2*t^-2), t = 0 .. infinity);

print(`output redirected...`); # input placeholder
1 |
- |
2 \
            /     /                    / 2            \
  1   (1/2) |     |                    |t  + csgn(x) x|
- - Pi      |limit|exp(4 csgn(x) x) erf|--------------|
  2         \     \                    \      t       /

                           /  2            \                  \\
                           |-t  + csgn(x) x|                  ||
   - exp(4 csgn(x) x) - erf|---------------| + 1, t = 0, right||
                           \       t       /                  //

   + Pi     | exp(-2 csgn(x) x)


It comes from Peirces's Tables No 510.

I have notice that Maple's integrator is very efficient.It is one  integral from these tables that Maple can't handle directly.

To be contined later.



I define unit vectors as

delta[1] := Vector(3, {(1) = 1, (2) = 0, (3) = 0})

delta[2] := Vector(3, {(1) = 0, (2) = 1, (3) = 0})

delta[3] := Vector(3, {(1) = 0, (2) = 0, (3) = 1})

Then I manually take the dot product as

Eq3 := delta[1].delta[1]+delta[1].delta[2]+delta[1].delta[3]+delta[2].delta[1]+delta[2].delta[2]+delta[2].delta[3]+delta[3].delta[1]+delta[3].delta[2]+delta[3].delta[3]

and get

Eq3 := 3

But when I do this

Eq4 := sum(sum(delta[i].delta[j], j = 1 .. 3), i = 1 .. 3)

I get

Eq4 := Vector(3, {(1) = Vector(3, {(1) = 1, (2) = 1, (3) = 1}), (2) = Vector(3, {(1) = 1, (2) = 1, (3) = 1}), (3) = Vector(3, {(1) = 1, (2) = 1, (3) = 1})})

How can I make Maple give me the first result using the sum command?




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
end do:end do:

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

 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 found an error in a file I posted that I would like to correct. Can I modify the existing post? Delete it and make an new one?

4 5 6 7 8 9 10 Last Page 6 of 1209