Hello all

I have a set of differential equations and its numerical solution, for two functions. Here's the worksheet (just a part of it, I don't need the rest)

##########################################

eq1 := diff(W(r), r) = -(1-beta*(W(r)-W0))*(M(r)+4*Pi*r^3*p(r))/(beta*r*(r-2*M(r)));

eq2 := diff(M(r), r) = 4*Pi*r^2*rho(r);

W0 := solve(thetaR = theta0-W0, W0);

r0:=10^(-5);

rf:=10^20;

# ini := evalf({M(r0) = 0, W(r0) = W0});

How to include/code/type such type of boundary conditions in maple?

Thanks

I need to update prcLeastSquareLA so that it adds error estimate information as an output in prcLeastSquareLA.

This is what I have so far:

prcLeastSquareLA:=proc(data,degree)

local vars,y,A,V,k,e,i,j,v,c,lstVars;  

vars := seq(c_i, i = 0 .. degree);

y := unapply(`+`(seq((c_i)*t^i, i = 0 .. degree)), t);

 for k to nops(data) do 

e_k := y(data[k][1]) = data[k][2];

v_k := [coeffs(lhs(e_k))];

I wrote the following code but am stuck on how to Update prcLeastSquareLA, so it does what prcLeastSquare does.

I believe you have to add error estimate information in prcLeastSquareLA but I have tried to no avail.

prcLeastSquareLA:= proc(data,degree)
local vars,y,A,V,k,e,i,j,v,c,1stVars;

vars:= seq(ci, i=0..degree);
y:=unapply(‘+’(seq(ci*t^j, i=0..degree)),t);
for k

Hi, I need to update a procedure prcLeastSquareLA so that it includes error estimate information as output in it. So far for the procedure I have this:

prcLeastSquareLA:=proc(data,degree)

local vars,y,A,V,k,e,i,j,v,c,lstVars;  

vars := seq(c_i, i = 0 .. degree);

y := unapply(`+`(seq((c_i)*t^i, i = 0 .. degree)), t);

 for k to nops(data) do 

e_k := y(data[k][1]) = data[k][2];

v_k := [coeffs(lhs(e_k))];

How to extract affine terms from a differential equation after linearization?

Vanderpol Eqn:

To be precise, I linearized...

i use Infeld's The Factorization method and find this Hermit is type D. since not exactly match r i use R(x,m) = r(x,m) + f(m) and compare them, then find k = x but eigenfunction Y := C*exp(-int(x,x)); has constant C, range x should between negative infinity and infinity. C is 1/Pi^(1/4) after solved. i guess this is wrong, but i do not know where is wrong.

another problem is that i assume C = 1, after sum for generating function the solution is not the same as mentioned in book which is exp(2*x*z-z^2)...

Hello,

1-I have one calculation and the result is "Error, (in expand/bigprod) object too large"... What can I do with this error?

thamks alot.

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I mean, if you consider a certain mass of water and you put it, for example on a fridge. I don't consider the convection but only the diffusion, and I would like to model, if possible with an animation the temperature of the water (as a cube for the shape).

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Modify the shortest path problem by rewriting a procedure Path, non-Recursion
 that print out the shortest path from a to e base on the information from
 setShortestDistNode
 input:  destination "e" and setShortestDistNode
 output:  path : a -> b -> d -> e the total cost: 9
hint: copy everything that we did in shortest path problem, and rewriting a procedure Path, with while loop

I'm assuming this means this, but...

Modify the shortest path problem by rewriting a procedure Path, non-Recursion
 that print out the shortest path from a to e base on the information from 
 setShortestDistNode
 input:  destination "e" and setShortestDistNode
 output:  path : a -> b -> d -> e the total cost: 9
hint: copy everything that we did in shortest path problem, and rewriting a procedure Path, with while loop 

can...

I adopted the approach suggested in an earlier post (http://www.mapleprimes.com

/questions/137320-Plotting-A-System-Of-Ode) for the known results,

but some part of curve is missing.

The output I got is

Can I create an tensor in the Physics package in Maple 16 with a free index like i=1..N:

A[mu,1]:=A[mu]

A[mu,2]:=B[mu]

.

.

.

and so on? The index is not one of the type gauge, spacetime or spinor.

Can you expalin the difference between the gaugeindices, spinorindices,and spacetimeindices in the Physics package in Maple 16? 

Hi, I have created 2 annulus;

> display(sector([2, -5.5], 2.5 .. 3.5, (1/5)*Pi .. (1/2)*Pi, color = "Niagara Burgundy"), axes = none, scaling = constrained);
%;

> display(sector([5, -5], 1 .. 1.5, (1/5)*Pi .. 2*Pi, color = "Green"), axes = none);

But I want the green annulus to cross the Niagara Burgundy annulus at the points where the green annulus is open. The green annulus is open with an angle...