Hi my dear friends, sorry for boring you. I am hauted by a problem about 'mtalyor'.

I failed to expand the following equation by using the following command:

u:=x(t)/sqrt(x(t)^2+y(t)^2-2*x(t)+1)*diff(y(t),t);
indets(u,name);
w:=evalindets(u,function(identical~({x(t),y(t)})),s->op(0,s)(freeze(op(s))));
var:=indets(w,name) minus {t};
mtaylor(w,var,4);
thaw(%)

 Freeze is applied to the part in which the expansion will take place, obviously it didn't work well. 

Thank you in advance for taking a look. 

To gererate a random initail cofigration -1 or 1

spin = (-1).^(round(rand(N)));

for i=1:1000,

neighbours = circshift(spin, [ 0 1]) + ...

circshift(spin, [ 0 -1]) + ...

circshift(spin, [ 1 0]) + ...

circshift(spin, [-1 0]);

how to do this in maple?

Hello

I was looking for information on how to solve a differential equation in Maple, but I do not know how to start.

I have yet equations in symbolic form and I want to apply for the calculation of such a procedure ODE4 (Runge Kutta 4) with fixed step integration Tc and time calculations ongoing T.

Where to start?
1. This should be done in another sheet, or I could write command in next line under the symbolic transformations?
2. To enter numeric parameters that certain symbols were they equal?
3. How to perform iterative calculations?

Thank you in advance for your help

Dear friends,

after looking through your site for some time I could not find any instructions on how to change my avatar (green caleidoscope pattern at this time). Could you advise me on this? Thank you.

Best regards,

Marko Riedel

PS: If you are answering this, when I enter my website into my profile it says the link is invalid, could that possibly be because there is a tilde in the link and therefore it fails to match a regular expression somewhere? Could we get a more precise error message from the profile validator?

I am curious, can simplify/siderels be executed in mod p by some equivalent Maple function call?

Hi, I have the equations (below) with different parameters. I'd like to find out if is it possitble to:

(1) Create a loop that solves for values of on of the parameters, T, in the interval -0.3<T<0.3 and obtain the solutions allowing for a grid of 0.01.

That is, if one can first solve for T= -0.3 and then use the loop with increments that raise T by 0.01 each time until T=0.3. Other parameters are held constant at their assigned values.

(2) Generates the corresponding vectors for T and all the endogenous variables.

eq1 := PI_T = alpha*M*(kappa/(1+kappa-sigma)-1):
eq2 := l = alpha*((sigma-1)*kappa/(1+kappa-sigma)+1):
eq3 := M = phi_c^(-kappa)*F:
eq4 := e*F = PI_T*v+T:
eq5 := M*l+L_A = L_s:
eq6 := F*e+A = A_s:
eq7 := A = (1-beta)*(L_s+(1-v)*PI_T-T):
eq8 := A_s = L_A:
eq9 := p = sigma/((sigma-1)*phi):
eq10 := P_Y = M^(lambda/(1-sigma))*p:
eq11 := L_s = N*(theta*P_Y^beta)^(-1/delta):
eq12 := phi = (kappa/(1+kappa-sigma))^(1/(sigma-1))*phi_c:
eq13 := U = delta*theta*L_s/((1+delta)*P_Y^beta)+((1-v)*PI_T-T)/P_Y^beta:

Params:= [ T=0, N = 1, v = 1, beta = .75, lambda = 1, sigma = 5, kappa = 4.8, delta = 2, theta = 2.591350635, alpha = 0.3998699153e-1, e = 0.8333333332e-1]:

Init_Values:= {A_s = .2500000000, l = .9996747882, PI_T = 0.8333333332e-1, L_A = .2500000000, phi = 1.878101496, M = .4168022157, A = .1666666667, p = .6655657336, P_Y = .8283396488, L_s = 2/3, phi_c = 1.2, F = 1, U = 1.326439132 }:

SOL:= fsolve(eval({eq||(1..13)}, Params), Init_Values);

Many thanks!!

Hello there,

Suppose I have a parametric experssion like   P(ε)=1+ε+ε²+ε³ where ε is very small. How can I get P(ε)≈1+ε or P(ε)≈1+ε+ε²? 

Thanks

I would like to remove from a table, the index that verifies some constraint.

For example :

restart:
a := table([1=c, 2=g, 3=y]);

for k in [indices(a, `nolist`)] do
  if is(k, even) then
    a[k] := 'a[k]':
  end if:
end do:

# This does not work as expected 
eval(a);

I have found this workaround 

b := map(u -> if `not`(is(u, even)) then u=a[u] end if, [indices(a, `nolist`)]);
eval(b);

But is there a way to force Maple to evaluate k to 2 before it "unevaluate"  'a[k]' ?

I would like to know , what is the command that i able to carry out (simple one) such that I able to shaded the region between y=x^2 and y-axis from y= 0 to y=4.

Hi all

If I have an expression:

B := int(A(x), x = -infinity .. infinity)

How can I use a statement to extract A(x) when A(x) is quite complecated during calculation. thanks

" there were problems during the loading process. your worksheet may be incomplete"

I have seen some other people having this problem, I have tried to erase the bad characters myself but I can't seem to do it right. Can someone pleeeease help me? :(

https://drive.google.com/file/d/0B5FKHYOiyQ0jMk9XNzBYU3FDbzQ/view?usp=sharing

Hello.

int(floor(x^2), x = 0 .. 2) = 6 , but it should be 1.85374.

Bug_in_integrate(floor_and_ceil).mw

Mariusz Iwaniuk

With the following equation

eqn:=y=1/2+(1/2)*erf((1/2)*sqrt(2)*(x-mu)/sigma)-exp(-lambda*(x-mu)+(1/2)*lambda^2*sigma^2+ln(1/2-(1/2)*erf((1/2)*sqrt(2)*(lambda^2*sigma^2-lambda*(x-mu))/(lambda*sigma))));

and with

x:=solve(eqn,x) assuming sigma > 0, lambda > 0;

I got the following solution

x := -(1/2)*(-lambda^2*sigma^2-2*lambda*mu+2*RootOf(-exp(_Z)*erf((1/4)*sqrt(2)*(lambda^2*sigma^2+2*_Z)/(lambda*sigma))+exp(_Z)+erf((1/4)*sqrt(2)*(-lambda^2*sigma^2+2*_Z)/(lambda*sigma))+2*y-1))/lambda;

In order to get rid of RootOf I gave the command:

allvalues(%);

However, RootOf did not disappear. How should I proceed? 

hi

if possible to convert matlab file in to maple fie program??convert_to_maple_program.txt

thanks

Download non_newtonian_non_darcy.mw

hai All,

i have problem to soilve pde in the maple

can anyone suggest / idea to solve in maple?