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I want to omit the independent variable

for example:

> alias(f = f(x+y, z+y));
print(`output redirected...`); # input placeholder
                               f
> f1 := z = f(x+y, z+y);
print(`output redirected...`); # input placeholder
       ...

How implementing in Maple this MATLAB's sequence?

timing_data = 0:0.01:5;
X = timing_data; %(s)
delta_t = mean(diff(X))

delta_t =

    0.0100

Gracias

Hi,

I'm trying to creat u which is a function of ξ. but I do not have the full definition of u yet. how can i write it in a way where when i differentiate it, it'll give me something like u(ξ),_ξ? And that i can differentiate it once more with ξ and it gives me u(ξ),_ξξ and so on?

please advice. Thanks.

I want to evaluate - del(psi)/del(x) analytically in MAPLE. I wrote the following lines for the purpose :

deltat := proc (x) options operator, arrow; lambda*x^m end proc

Gr := proc (x) options operator, arrow; g*beta*deltat*x^3/nu^2 end proc

xi := proc (x) options operator, arrow; g*beta*x/c[p] end proc

eta := proc (x) options operator, arrow; (1/4)*y*4^(3/4)*Gr^(1/4)/x end proc

psi := proc (x, y) options operator, arrow; nu*4^(3/4...

I have an ODE to solve that looks like this: 

((diff(R(r), r, r, r, r))*r^4+3*(diff(R(r), r))*r-3*(diff(R(r), r, r))*r^2+2*(diff(R(r), r, r, r))*r^3-3*R(r)+4*R(r)*n+2*R(r)*n^2-4*(diff(R(r), r))*r*n+2*(diff(R(r), r))*r*n^2+4*(diff(R(r), r, r))*r^2*n-2*(diff(R(r), r, r))*r^2*n^2-4*R(r)*n^3+R(r)*n^4)/r^4 = (-108-1362*n+2122*n^2+2019*n^3-3032*n^4+401*n^7+1192*n^6-1033*n^5-25*n^9+6*n^10-180*n^8-4128*r^(n+3)*n^3+2304*r^(n+3)*n-576*r^(n+5)*n-760*n^6*r+575*n^5*r-244*n^7*r-2108*n^3*r-11616*r^(n+3...

Hey there,

i´ve a numerical solved differential equation and a "normal" equation. How can i calculate the differenz of both?

>S:=0.79*cos(t)+0.3*sin(t);

> DGL1 := 20*(D(D(x)))(t)+10*(D(x))(t)+2500*x(t)+300 = S;
> init := x(1.2) = 0, (D(x))(1.2) = 10.63081252;
> F := dsolve({DGL1, init}, numeric);
>U:=F-S;

> p1 := plot(U, [t, x(t)], 1.2 .. 2, numpoints = 200);
%;
Error, (in plot) two lists...

Why the result can't execute?

Can anyone explain the rationale behind plot command, which generates the same graph differently for an identical function?

> restart;
> with(plots); with(plottools);
m := 4;
k := 20;
omega[n] := sqrt(k/m); 
T[n] := evalf(2*Pi/omega[n]); 
td := 0.5*T[n]; 
ratio := evalf(td/T[n]);
p3 := 4*sin(Pi*t/td);
dur := evalf(2*Pi);

enc := u(0) = 0, D(u)(0) = 0; 
eq := m*(diff(u(t), t, t))+k*u(t) = p3; 
sol := unapply(rhs(dsolve([eq, enc])), t); 

I have a region x^2 + y^2 <= 1 and y>=0. It's temperature function is f(x,y) x^2 - 2y^2 + x + y. How do I find the max and min temperatures on the lower boundary y=0?

I took the derivatives with respect to x and with respect to y such that:

fx:=diff(f(x,y),x);

fy:=diff(f(x,y),x);

Then I used fsolve({fx=0, fy=0},{x,y}) which game me (-0.5, 0.25)

Is there really only one critical point on that lower bound...

Hi..I need to plot the slope field for a diffEQ and having problems. I have a Maple 14 program that I just had to reinstall due to a virus and hoping that isn't the problem.  I'm very new to Maple and I'm not a good programmer, so any light you can shed on my problems would be much appreciated.  When I enter the problem, I don't get any error message or anything...just a blank return!  This is what I tried:

with(DEtools):

DEplot (diff (y(x...

Hello,

I am trying to run maple file for k=1, k=2 ....

My do-loop did not work. What I would like to do is to solve the ODE then have new inc and solve it again.

I should have U(405) then U(770) ....

> restart;

> with(DEtools); with(plots);

> lambda := 0.1; delta := .5;

tau := 40;

> for k to 3 do 365*k end do;

> ode := diff(U(t), t) = -lambda(t)*U(t)*U(t);

> inc1 := U(0) = 100;

What is the difference between them?

daesys0:={diff(I3(t),t) = 1/L*u(t), I1(t) = I3(t) + 1/R * u(t), I3(0)=0, I1(0)=0};

and

daesys0:={diff(I3(t),t) = 1/L*u(t), I1(t) = I3(t) + 1/R * u(t), I3(0)=0};

If I use the procedure for numerical solution, their solutions are similar.

Hello,

I'm trying to solve the following system in Maple but it doesn't show me any solution:

where x(0)=0 and y2(0)=0 , k>0,...

try_IG.mw

The following codes is a part of my program for computing ING at several points of r between -1 and 1 (by a step of for example 0.1 or even smaller for a better pointplot of ING(r) ):

H:=(r, teta) -> h(r, zn, teta) # h is a complicated function of (r, z, teta) (referred to the attached maple file) and   zn is a given number

F:= r -> int(H(r, teta), teta= 0…alpha)

Hello! How i can write this expression in maple?

ma × (Ω' × a )

where is

Omega := Vector(3, [Omega1, Omega2, Omega3])

dT := proc (f) options operator, arrow; add((diff(f, var[k]))*dz[k], k = 1 .. N) end proc

a := Vector(3, {(1) = Ri*n1, (2) = n2*Ri, (3) = n3*Ri-R0})