janhardo

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11 years, 101 days

MaplePrimes Activity


These are answers submitted by janhardo

restart;
f := 419*x^2 + 116*x*y - 426*x*z + 78*y^2 - 142*y*z + 133*z^2 - 1604*x - 682*y + 1086*z + 2306;
df_dx := diff(f, x);
df_dy := diff(f, y);
df_dz := diff(f, z);
centrum := solve({df_dx = 0, df_dy = 0, df_dz = 0}, {x, y, z});
                      "maple.ini in user"

             df_dx := 838 x + 116 y - 426 z - 1604

              df_dy := 116 x + 156 y - 142 z - 682

             df_dz := -426 x - 142 y + 266 z + 1086

               centrum := {x = 7, y = 11, z = 13}

It is a quadratic surface, with this point : centrum ? : point symmetry around centrum, needs more info.

eqt1 := u(x, y, 0, t) = 4*alpha*(-lambda[1]*t*(lambda[1]^2 - 3*lambda[2]^2)*alpha + (b*lambda[1] + ((r[1] + r[2])*c)/2 + a)*t + beta*(y*lambda[1] + x))*lambda[2]^2*beta/(lambda[2]^2*t^2*(lambda[1]^2 + lambda[2]^2)^3*alpha^3 + 3*t*lambda[2]^2*alpha^2*(2*(b*t + beta*y)*lambda[2]^4/3 + t*c*(r[2] - r[1])*lambda[2]^3*I/3 + 2*lambda[1]*((((r[1] + r[2])*c)/2 + a)*t + x*beta)*lambda[2]^2 - lambda[1]^2*t*c*(r[2] - r[1])*lambda[2]*I - (2*lambda[1]^3*((b*lambda[1] + ((r[1] + r[2])*c)/2 + a)*t + beta*(y*lambda[1] + x)))/3) + lambda[2]^2*((b*t + beta*y)^2*lambda[2]^2 + t*c*(b*t + beta*y)*(r[2] - r[1])*lambda[2]*I + ((b*lambda[1] + c*r[2] + a)*t + beta*(y*lambda[1] + x))*((b*lambda[1] + c*r[1] + a)*t + beta*(y*lambda[1] + x)))*alpha + beta^2)

Can this function be used now ?

@Alfred_F 

There are some corrections  to make for the procedure FastPursuite 
Handling the ode system in Maple for this procedure can be different on two ways.


As you can see the goat is escaping the wolf ..lol,  message (  try  correct this  and add  coordinat axes)



The procedure approach:

@Alfred_F 
A bijective function cannot be periodic ?

sol := dsolve([de1, de2, bc], numeric, method = bvp[midrich], approxsoln = [y(x) = 1 - exp(-x), z(x) = exp(-x)], abserr = 0.1e-5, maxmesh = 128)

` Solve using BVP with midrich method (collocation-type)`

 


Angular Motion Over Time

restart;
grid := proc(M::Matrix) local i, j, Ms, m, n, wks; m, n := op(1, M); Ms := map(convert, M, string); wks := XMLTools:-ToString(_XML_Worksheet(DocumentTools:-Layout:-Table(':-alignment' = ':-center', ':-width' = 20, seq(DocumentTools:-Layout:-Column(':-weight' = 3 + max(map(length, Ms[() .. (), j]))), j = 1 .. n), seq(DocumentTools:-Layout:-Row(seq(DocumentTools:-Layout:-Cell(`_XML_Text-field`("alignment" = "centred", "style" = "Text", Ms[i, j])), j = 1 .. n)), i = 1 .. m)))); streamcall(INTERFACE_TASKTEMPLATE(':-insertdirect', ':-content' = wks)); NULL; end proc;
data := [["Case", "Optimal Pc"], ["μ₁ = 0, μ₂ = 0", "Pc₁"], ["μ₁ = 0, μ₂ > 0", "Pc₂"], ["μ₁ > 0, μ₂ = 0", "Pc₃"]];
grid(Matrix(data));

Is this correct ?


 

restart; with(PDEtools); with(plots); declare(w(r, z)); eta := 1; lambda := 1; A1 := 1; A2 := 1; A3 := 1; Da := 1; M := 1; m := 1; UHS := 1; Phi := (1/4)*Pi; dpdz := -1; N := 1; w[0] := proc (r, z) options operator, arrow; (1/2)*r^2-(1/2)*eta^2 end proc; w_total := proc (r, z) options operator, arrow; sum(p^n*w[n](r, z), n = 0 .. N) end proc; HPMEq := (1-p)*(diff(w[0](r, z), r, r))+p*(diff(w_total(r, z), r, r)+(diff(w_total(r, z), r))/r-(1+lambda)*(dpdz+A2*M^2*w_total(r, z)+A1*w_total(r, z)/Da-m^2*UHS*BesselI(0, m*r)/BesselI(0, m*eta)+A3*sin(Phi))/A1); for i from 0 to N do equ[i] := coeff(expand(HPMEq), p, i) = 0 end do; bc[0] := (D[1](w[0]))(0, z) = 0, w[0](eta, z) = 0; for j to N do bc[j] := (D[1](w[j]))(0, z) = 0, w[j](eta, z) = 0 end do; for i from 0 to N do if i = 0 then w[i] := unapply((-eta^2+r^2)*(1/2), r, z) else try dsol := dsolve({equ[i], w[i](eta, z) = 0, (D(w[i]))(0, z) = 0}, w[i](r, z)); w[i] := unapply(rhs(dsol), r, z) catch: print(`No analytic solution found for order`, i); w[i] := proc (r, z) options operator, arrow; 0 end proc end try end if end do; W_final := eval(sum(w[n](r, z), n = 0 .. N), p = 1); W_final := simplify(W_final); if has(W_final, w[1]) then print("Warning: Solution contains unresolved w[1] terms - using numerical approach"); W_plot := eval(W_final, w[1](r, z) = 0) else W_plot := W_final end if; plot(eval(W_plot, z = 0), r = 0 .. eta, title = "Velocity Profile w(r,0)", labels = ["r", "w(r,0)"], labeldirections = [horizontal, vertical], color = blue, thickness = 2, gridlines = true); plot3d(W_plot, r = 0 .. eta, z = 0 .. 1, title = "Velocity Distribution w(r,z)", labels = ["r", "z", "w(r,z)"], style = surfacecontour, shading = zhue, axes = boxed)

w(r, z)*`will now be displayed as`*w

 

1

 

proc (r, z) options operator, arrow; (1/2)*r^2-(1/2)*eta^2 end proc

 

proc (r, z) options operator, arrow; sum(p^n*w[n](r, z), n = 0 .. N) end proc

 

1-p+p*(5+p*(diff(diff(w[1](r, z), r), r))+(r+p*(diff(w[1](r, z), r)))/r-2*r^2-4*p*w[1](r, z)+2*BesselI(0, r)/BesselI(0, 1)-2^(1/2))

 

1 = 0

 

5-2*r^2+2*BesselI(0, r)/BesselI(0, 1)-2^(1/2) = 0

 

0 = 0, 0 = 0

 

(D[1](w[1]))(0, z) = 0, w[1](1, z) = 0

 

`No analytic solution found for order`, 1

 

(1/2)*r^2-1/2

 

(1/2)*r^2-1/2

 

(1/2)*r^2-1/2

 

 

 

NULL


 

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