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Is there a way to solve an equation to show all integer solutions, assuming the problem has finite solutions. Examples would include elliptic curves.

I have the following list, vector or set, I put it in a matrix




Does any body know why the following code

A:=Matrix(3, 3, [[-1/23*(14+21*62^(1/2))^(1/3)-31/29/(14+21*62^(1/2))^(1/3)-13/107,0,0],[0,1/22*(14+21*62^(1/2))^(1/3)+15/29/(14+21*62^(1/2))^(1/3)-13/10-1/2*I*3^(1/2)*(-1/11*(14+21*62^(1/2))^(1/3)+31/29/(14+21*62^(1/2))^(1/3)),0],[0,0,1/22*(14+21*62^(1/2))^(1/3)+15/29/(14+21*62^(1/2))^(1/3)-13/10+1/2*I*3^(1/2)*(-1/11*(14+21*62^(1/2))^(1/3)+31/29/(14+21*62^(1/2))^(1/3))]]) ;



I'm trying to use a simple DLL in maple, which I create based on Maple external linking examples..

int __stdcall mult( int a, int b )
         return a * b;

and I compiled it with Visual Studio 2010 compiler, but when I use it in Maple I recieve the error

"Error, external linking: error loading external library"


Of course the bottleneck is in Maple (may I say as usual, especially when you are trying to innovate).
i) Socket package is not thread safe
ii) Most of the time is spend waiting for Wait(id1, id2) etc

If all the technical Maple stuff was working I could do the below call in around 1 second or less.
Now it takes 7 seconds which is way way to long if you want to download let say 50 symbols...

X := proc(symb)
  uses Sockets;

Hi.  I am supposed to sketch the set of points in the complex plane defined by


where <= is less than or equal to and I is the complex number.

By hand, we simply substitute z=x+I*y into the above inequality, expand and simplify to get


From here onwards, we sketch the straight line and shade the bottom region of the line.

In more challenging cases rather than getting a straight line, one...

r(t):= <t | t^(2) | (t^(2) )/(2) >

simplify(simplify(PrincipalNormal(r(t), t, normalized), symbolic),symbolic)


The three lines above are part of a worksheet that computes unit tangent vector, unit normal vector and components of acceleration for a parametric curve r(t) ,  a standard Calc 3 lesson.

I am...


I have one calculation and the result is "Length of output exceeds limit of 1000000"... What can I do with this error?

Thanks a lot.

Hi, I'm trying to use rsolve to solve the difference equaiton: y(n)-3*y(n-1)-4*y(n-2)=delta(n)+2*delta(n-1)  where deta(n) is the discrete delta function represented by charfcn[0](n).  The answer should be y(n)=(-1/5)*(-1)^n+(6/5)*4^n.  I'm getting the answer in terms of y(0) and y(1) and extra terms.  Can someone point me in the right direction?

Thanks for your help

Is it possible to specify tolerances such as +10,-5 instead of just +-10?  In other words, can the high and low limits be different?  Thanks, Ratch


August 26 2010 mehrdadparsapour 18

Fsolve solve for numeric when I put X as an parameter in one of the equation it get an error

y1 := 2*a*b^2-b+c-d-1 = X;
y2 := a^4+b^3-b^2+c-d+2 = 0;
y3 := a*b^2-b+c-d-3 = 0;
y4 := a^3*b^2-b+c-d^3+4 = 0;
fsolve({y1, y2, y3, y4},{a,b,c,d})

Error, (in fsolve) X is in the equation, and is not solved for

5) Look at the below code. It takes 7 seconds to make the call to yahoo finance 4 times
sequentially. The strange thing is that it takes the same amount of seconds to do the call
in parrallel....hummm very strange....what is the benefit of using the Task command then ??
I have 4 cores in my machine ie kernelopts(numcpus) returns 4 so it should be very fast.


X1 := proc (...

I want to fill a matrix m by m with elements

1) the elements under the diagonal comes from the expression

Gama:=(i, k)→evalf(((x[k]-x[i])*xdot[k]-(y[k]-y[i])*ydot[k])*dtheta[i]/((x[k]-x[i])+(y[k]-y[i])^2))

2) the elements in the diagonal comes from Lambada:=(i)→-sum(Gama, k=1..M), where i<>k

I've tried to install maple 10 in windows vista but it seems imposible the setup keeps saying this.."please wait, maple 10 is being configured for your system, this make take a moment..." i've left my computer on all night but the installation doesn't end...any ideas on how to solve this problem? thank you.

Could you please explain the following:

1) str1 and str2 should be global variables right? I mean so we can call them
after the Create statements....

2) When I execute the below code and then call str1 and str2 I dont get any html output.
The " " are empty.....why?


X1 := proc () local str, sid, b;  global str1;

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