I have this Maple code that calculates the Sharpe ration= Expected return portfolio / Standard deviation return portfolio
for a pair of stocks by using permuations [ stock[i], stock[i] ]. Each stock shows up the permuation list twice first in
[ here, not here ]  and  [ not here, here ] so I just itterate over such permuation list and take a long position in the
first stock ( +1*return) and a short position in the second stock (-1*return). So I get the Sharpe ration for all

Hi all I'm using a set of parameters, such as {a=1.b=2,c=3} to do various manipulations of an ODE system. Then later I want those parameters to be assigned their respective values, but I'd rather not have to do a:=1;b:=2;c:=3 Is there a way to do that ? Thanks LR

Dear All:

  I have type such expression in maple 2D Input

L[out_inductor] := 8e-6;

The result shown as L[out_inductor] := 0.80e-5; but if i change the numeric formatting to scentific, the result style change as below: 8.00*10^(-6) , the variable name L[out_inductor] missed in 2D output , it still disppeared even i change numeric formatting to none.

so i want to need some help me, how can i let variable name L[out_inductor] show in 2D output when the numerric formatting is scentific.

This problem has ocurred a few times and is quite troublesome.

Does there exist a way in Maple that you can detect a change in a text file without having
to constantly having to call the readdata which keep the command prompt busy in Maple.
For example if you have a txt file that is constantly updating it self with new data
I want the matrix in Maple to be updated dynamically by adding the new data.
Is this possible ?

I am trying to code a naive method for checking if a number is prime. where it checks if a number is prime by checking if a number 'k' divdes into n.

 

Hello, i have attached the file here.

Basically i have an eighth order equation in m. This will produce eight solutions of m. Then i need to substitute each solution of m into a matrix, say M. Thus generating a matrix for each m value. Can someone show me how to do this please...

Greetings Is there a nice way to obtain the jacobian of a system of ODEs ? For example with restart: ross_x:=diff(x(t),t)=-y(t)-z(t): ross_y:=diff(y(t),t)=x(t)+a*y(t): ross_z:=diff(z(t),t)=b+x(t)*z(t)-c*z(t): rossler_sys:=ross_x,ross_y,ross_z; I can't seem to find an easy way to do it, other than re-write the system altogether s_x:=-y-z: s_y:=x + a*y: s_z:=b+z*(x-c): J:=Matrix([[diff(s_x,x),diff(s_x,y),diff(s_x,z)],[diff(s_y,x),diff(s_y,y),diff(s_y,z)],[diff(s_z,x),diff(s_z,y),diff(s_z,z)]]); .....which seems horrible. Thanks LR

Hello! Why does Maple not compute the following residue? residue(((x^7+1)^4/x^30), x=0); Maybe the powers are too high? Are there any parameters I can set so that Maple produces a result? Thanks! Marco

How can I tell Maple to read all txt files in a specified folder ?
The names of each txt files are different ( I dont know the names )

Using maple help: wiht(plots): animate(plot, [Ax^2, x = -4 .. 4], A = -3 .. 3, trace = 5, frames = 50) the above command shows a plot with no animation... What's wrong?

*sigh* Mathematica,

 

how do I plot the bifurcation diagram with Maple of the function:

 

dx/dt = rx - sin(x) ?

My goal: given G(z,w), find the polynomial, P(n), in the partial derivatives of G(z,w) over the integer such that 

d^n z/ dw^n = P(n) / Gz^(2n-1)    where Gz= partial derivative of G with respect to z.

Step 1. Differentiate G(z(w),w) w.r.t w n times. Formulae are known for doing that (Mishkov, Tsoy-Wo Ma),

I came across this issue on my course today, and found it somewhat surprising: restart:Digits:=7: foo:=1/2*sqrt(3): evalf(foo); 0.8660255 evalf[5](%); 0.86603 evalf[5](foo); 0.86605 I suppose this means that whatever algorithm Maple uses to compute the square root also works to the specified level of accuracy and the above is a result of accumulated rounding errors.

question1:

with(Optimization)

Minimize((1-b^2)/a+(1-c^2)/b+(1-a^2)/c, {a^2+b^2+c^2 = 1}, assume = nonnegative)

the result is strange:

[3.46410161513774462, [a = .577350269189626620, b = .577350269189626620, c = .577350269189626620]]

make the datatype not the float form in the results. 3.4641... to 2 sqrt(3)

question2:how to do this.I use sqrt(1-a^2-b^2) to substitute for c.

Minimize((1-b^2)/a+(1-a^2)/sqrt(1-a^2-b^2)+(a^2+b^2)/b, assume = nonnegative)

question3: