Homework questions are welcome as long as they are asked honestly, explain the problem, and show sufficient effort. Please do not use this as the only tag for a question. Please do not add this tag to questions by other people unless they explicitly say that their question is part of their homework.
1
vote
2answers
78 views
2D Schrödinger time-independent finite difference and eigenvalues
I'm learning about numerical methods to obtain the eigenvalues of a system. I have to find the eigenvalues for the time-independent Schrödinger equation but I'm having some difficulties understanding ...
3
votes
1answer
42 views
TypeError from scipy.optimize.curve_fit
I am trying to fit a data set to an exponential model using scipy. However, the covariance matrix that is returned is 'inf' and I receive the following error:
Traceback (most recent call last):
...
2
votes
1answer
32 views
Not Sure How to Solve A System Of Linear Equations In MAPLE13
How can one solve the following system of linear equations in MAPLE 13?I know how to solve a linear equation with one variable floating around but not this one.
$$x-2y+3z=10$$
$$3x-2y+z=2$$
...
4
votes
0answers
51 views
Solving diffusion PDE using finite differences
I need some hints on how to solve this diffusion equation ($\alpha, k_1,k_2$ and $k_3$ are constants):
$$ {\partial P \over \partial y} + k_1 {\partial P \over \partial t} + \alpha P = {1 \over k_2} ...
0
votes
1answer
57 views
Thermoplastic Equation solving
I was given a problem by my professor as follows
Solve the
System
$pV=S$
$pcT=kT+BS\frac{dG}{dt}$
$\frac{dS}{dt}=\mu(V-\frac{dG}{dt})$
$\frac{dG}{dt}=f(S,T)$
Where $p$, $c$, $B$, $\mu$ are ...
3
votes
1answer
78 views
multiplications of graph adjacency matrix
Suppose $A$ is a directed graph adjacency matrix. Is there any good interpration of the $(i,j)-$entry of the matrix $(A^{32}\cdot (A^T)^{32})$ ?
2
votes
0answers
152 views
Computing the pseudoinverse of a Hilbert matrix using an iterative scheme
I have made following matlab program for computing pseudoinverse of a Hilbert matrix of order 10. pinv(A) returns the pseudoinverse of A.
...
3
votes
2answers
119 views
How to prove that my problem is np-hard
For an assignment i need to program an application to schedule conversations. Something similar to speeddating or Pta meeting.
The problem is that i know that this is hard to solve, but i dont know if ...
3
votes
1answer
569 views
Gauss-Seidel iterations node spacing
I am working on an assignment where I am determining the temperature distribution of a chip on a substrate. When I decrease the nodal spacing the results change drastically. The smaller the nodal ...
3
votes
2answers
158 views
How to establish that an iterative method can be applied to large matrices whose size may reach 10^3?
I have an iterative method for computing the Moore-Penrose generalized inverse of matrices, that is
$$X_{k+1} = ((I-\beta X_{k}A)^t) + X_{k}$$
with initial approximation:
$$X_{0} = \beta AA^t$$
...
2
votes
2answers
459 views
Depth of a Binary Search Tree
I wrote a function to search a Binary Search Tree, but I have logic problems: When I insert some values, and I have a tree of 2 levels, and the final level (2 in this case) is not full (full is that ...
5
votes
2answers
125 views
Proving convergence of 5 point scheme for the Poisson equation
So, we are solving the Biharmonic equation ($\Delta^2 u = f$) on a rectangle by solving the Poisson equation ($\nabla^2 u = f$) two times. We have nice boundary conditions, $u = 0$ and $\Delta u = 0$ ...
8
votes
2answers
1k views
How to impose boundary conditions in finite difference methods
I have a problem when I want to use the high order center difference approximation:
$$\left(\frac{-u_{i+2,j}+16u_{i+1,j}-30u_{i,j}+16u_{i-1,j}-u_{i-2,j}}{12}\right)$$
for the Poisson equation
...
-5
votes
1answer
240 views
Successive over-relaxation formation of heat equation?
What is the form of SOR iterative equation for the heat equation
$u_{xx}=u_{t}-1$ using centered differences both in time and spatial
derivatives and using Crank-Nicolson method?
...
