restart:

Eq1:=(-1/k)*B*(diff(-f(r),r$3)-(1/(r+k)^2)*diff(f(r),r$1)+(1/(r+k))*diff(f(r),r$2)+(1/(r+k)^2))

-((r+k)/k)*B*(diff(-f(r),r$4)+(2/(r+k)^3)*diff(f(r),r$1)-(2/(r+k)^2)*diff(f(r),r$2)+(1/(r+k)^2)*diff(f(r),r$3)

-(2/(r+k)^3));

bcs:=f(-h)=1/2,(D@@1)(f)(-h)=1,f(h)=-1/2,(D@@1)(f)(h)=1;

dsolve({Eq1,bcs},f(r));

Please have a look.

Thanks

One of my students just showed me the following strange behaviour with Maple 18 (17?) on her Mac computer:

After entering anything at all in math mode, the Enter key has no effect.

After an empty line in math mode the Enter key works fine, and also after anything (including nothing) in text mode.

She has uninstalled and reinstalled Maple several times.

I have absolutely no clue. Do you?

If nobody has a clue, I will be back with more detailed information.

Knud Fjeldsted
Denmark

Hello those who are in mapleprimes,

I want to devide both hand side of inequality by positive a.

And, the ways I want to know are two ways for doing this.

1)         c:=a<b: c/d assuming d>0;

returns 

I don't know why the result isn't a/d<b/d.

2)        the second way is one to focus on op(0,c) being <. And, from lhs(c), rhs(c), and op(0,c), 

I want to constract lhs(c)/d op(0,c) rhs(c)/d, that is lhs(c)/d<rhs(c)/d.

Please tell me about this.

Thank you in advance.

taro

Hi,

I am having trouble solving the PDE. Can anyone shine some light?

Download 1234.mw

cubic4.mw

I have created a multivariate polynomial with variables P1,...,P6, and would like to factor the poly in terms of (Px-Py) where x,y are combinations of 1-6 (x not equal y). I am new to Maple and have only tried the "Factor" and "Simplify" dropdown menu commands, but neither of these seem to produce anything remotely close to what I need.

Thanks

Derek

I would like to attach a maple document to refer to but dont see how to attach a document to this question.

Edit:

Having Uploaded the intended file, I can direct your attention to eqn (14) which is factored into (15) nicely, but when things get a little more complicated as in (45), the factored form in (46) does not contain any of the (Px-Py) forms I am looking for. Is there a way to steer the factor function toward certain forms?

Edit2:

divide.mw

As seen in this form of the problem statement (using quadratics instead of cubics), the divide function does not seem to capture the factorability. From file divide.mw (attached), eqns (19) and (24) are equivalent since the subtraction of the two produces 0 as seen in (28), however both the factor command (23) and the divide command (29) produce nothing substantive.

How do I make a timer to record the seconds elapsed between button clicks?

I would like to make a multiplication game for primary students and want to have it return a score that reflects how long it took to answer the question.  I've been through the help pages (i.e. the lunar lander module) so I know it can be done but I am a Maple novice and am having trouble replicating it.

Thanks for your help!

Hi, those who are in mapleprimes.

i have a problem in solving inequality with symbolic notated parameters.

I wrote the following code to solve for n(SPH), but couldn't obtain any result but an error message.

solve(-s*(-n(SPF)*tau+n(SPH))/(tau-1) <= n(SPH),n(SPH)) assuming (tau<1,s>0,s<1,tau>0);

The error was

Error, (in assuming) when calling 'unknown'. Received: 'invalid input: Utilities:-SetSolutions expects its 2nd argument, solutions, to be of type ({list, set})({piecewise, ({list, set})({name, relation})}), but received [s = -tau~+1, [SPF = SPF, s = s, tau~ <= 0]]'

Please tell me how I should do to solve the inequality.

Thanks in advance.

taro

i := I;

assume(a>0);

assume(b>0);

assume(r>0);

assume(k>0);

assume(w>0);

Hz := k*(z^2-2*r*a+r^2)/((z-1)*(z^2-2*b*z+1));

Hzw := eval(Hz, z = exp(i*w)); assume(a > 0);

Habs := simplify(abs(Hzw)^2);

p1 := eval(Habs, w = Pi) = (10^((-3.3018)*(1/20)))^2;

p2 := eval(Habs, w = (1/2)*Pi) = (10^((-.1758)*(1/20)))^2;

p3 := eval(Habs, w = (1/4)*Pi) = (10^(6.425*(1/20)))^2;

p4 := eval(Habs, w = (1/8)*Pi) = (10^(54.5699*(1/20)))^2;

solve({p1, p2, p3, p4})

eq1 := fracdiff(u0(x), x, 0.5)= 0 with initial u0(0)=0

and i need the value of  u0(x) to find u1(x) from

eq2 := fracdiff(u1(x), x, 0.5)+f = 0   for some function f

thank you

Say the values of i^2 are being calculated from within a procedure,

mytest:=proc(n)

local ans;

    ans:=0;

    for i from 1 to n do

   ans:=ans+i^2;

   end do;

   return ans;

end proc;

Could I have a (time series) plot of i^2, while the values are being calculated?

The above is a toy example. What I want to archieve is to track a particular intermidiate values while the procedure is running.

Thanks,

casper

It puzzles me that some of the choices for Clickable Math don't return a result. The image below shows four choices for clickable math. I would like it to "factor" exactly as shown in the upper left choice, but nothing happens after clicking the choice. (No matter how many times I try.) The choices "2D Plot" and "Isolate" return results ("Complete the square", in this case, also does not work).

My guess is that I'm asking it to operate on only the denominator of the rhs of the equation, but then why is the choice displayed at all. I've noticed this for some time in certain cases (like since version 17 was release).

Is there a way to make the choice return a result ? In this case, I don't find an equivalent command (factor, the denominator) using a right click. (In this case, I'll use another command "covert" "parfrac" . . .)

I want Clickable Math to make it easy.

Thanks. Cheers !

I was under the impression that I could declare the type of the return value from a procedure to be a tuple of two posints as follows:

  foo := proc () :: posint, posint; 12, 13; end proc;

and then use it for multiple assignment as

  i, j := foo();

Of course, I have to set

  kernelopts(assertlevel = 2):

if I want Maple to actually check that foo returns two posints as promised.

All this seems to work as expected, including getting an error message if the returned value has the wrong type.

So, why does Maple IDE claim that this is a syntax error? Is there a difference between the syntax accepted by Maple and Maple IDE, and if so which is correct?

I typed (x-a)(x-a) into Maple 18 (the only thing in a new document) and got x(x-a)-a 

I'm wondering why it is evaulated like this?

Is this because of a setting?

BTW, I evaluated at a=4 first. 

Here´s the problem:

I´m ussing the command readdata to import a large ammount of data from a .txt file. So far, so good.

The problem is when I have to switch computers from home to office and I need to work with my .mw file. Every time I do the switching between the computers I have to replace all the directory information for maple to read the .txt file in the new location.

Is there any way to tell maple to look for the file in a relative way instead of a absolute direction in the hard drive?

I know this is maybe a beginners question, but thanks in advance.

I tried to find the root distritubion of a polynomial? 

When p=1, q=3, the following command works.

with(plots):

eq:=u^(2*q)+1-2*K*u^(q-p);

p:=1;   q:=3;

unitcircle:=implicitplot(x^2+y^2 = 1, x = -1 .. 1, y = -1 .. 1, scaling = constrained);

animate(complexplot,[[solve(eq, u)],style = point,symbolsize=10,color="red"],frames=50,K=-1..1,background=unitcircle, scaling=constrained, trace=20 );

However, when I tried p=2, q=3, only one root was shown on the animation.  

But   "complexplot([solve(eq,u)],style=point)"      showed  6 roots anyway.

I have no idea what was wrong.