# Matthew Hunt

**Statistics**

RANK**27,531**

of 275,736

REPUTATION**1**

CONTRIBUTIONS

**34** Questions

**7** Answers

ANSWER ACCEPTANCE **
29.41%
**

VOTES RECEIVED**1**

RANK

of 18,573

REPUTATION**N/A**

AVERAGE RATING**0.00**

CONTRIBUTIONS**0** Files

DOWNLOADS **0**

ALL TIME DOWNLOADS**0**

RANK

of 125,549

CONTRIBUTIONS

**0** Problems

**0** Solutions

SCORE**0**

NUMBER OF BADGES**0**

CONTRIBUTIONS**0 Posts**

CONTRIBUTIONS**0** Public Channels

AVERAGE RATING

CONTRIBUTIONS**0** Highlights

AVERAGE NO. OF LIKES

**Content Feed**

Question

Code has numerical issues that I don't understand

I managed to get a system of PDEs down to a large system of ODEs via the method of lines. I managed to code it up using ode45 bu...

24 hours ago | 0 answers | 0

### 0

answersQuestion

How do you include a mass matrix in ode45?

ode45 solves a set of equations The length of is 3N+1, I have a non identity mass matrix M, but I've not seen any real ins...

9 days ago | 2 answers | 0

### 2

answersQuestion

User defined function within ode45

I have the following ODE system: If f(t) is a constant, then I can easily write the code, but I have f(t) as a piecewise ...

14 days ago | 2 answers | 0

### 2

answersQuestion

Can I get a better fit to data

I've written a code to find some parameters to a mathematical model but I can't seem to get a good fit to the experimental data....

2 months ago | 1 answer | 0

### 1

answerQuestion

Use of fmincon with objective function as m-file

I am finding parameters for a model. I thought the best thing was to define the objective function that I wiah to minimise as f...

2 months ago | 2 answers | 0

### 2

answersQuestion

Can we get functions from the curve fitting toolbox?

I am using the curve fitting toolbox and I have some data that I want to create a function from. I am using a spline function to...

2 months ago | 2 answers | 0

### 2

answersQuestion

Solving PDEs with mixed derivatives

Suppose I have an equation of the form: Can I use pdepe to solve that equation as is, or do I have to do a co-ordinate tran...

2 months ago | 0 answers | 0

### 0

answersImplementing Crank Nicholson in spherical setting

Question resolved.

12 months ago | 0

| accepted

Question

Implementing Crank Nicholson in spherical setting

I am trying to solve the spherical diffusion equation using the Crank-Nicholson method. I think that I understand the method, I ...

1 year ago | 3 answers | 0

### 3

answersQuestion

Code doesn't terminate in the way that I want

I have a loop which changes the value of a vector at each iteration of the loop. I don't want the values in the loop to get grea...

1 year ago | 1 answer | 0

### 1

answerQuestion

My implemetation for Newton's method doesn't seem to be working

My goal is to solve the following set of nonlinear equations: for this I use the Newton method in the form: The code t...

1 year ago | 1 answer | 0

### 1

answerQuestion

I want to do a 1D integral of some 2D data

Suppose I have a function which is defined as some numerical data which is equally spaced and I wish to compute: How would I...

1 year ago | 2 answers | 0

### 2

answersQuestion

Speeding up pdepe calculation

I have a pdepe bit of code I want to speed up if I can. I have a (typically) 400x800 array as a source term, the code I'm curren...

3 years ago | 0 answers | 0

### 0

answersQuestion

Importing a two variable function into pdepe

Hi I want to solve a diffustion pde I understand how to do this if Q is a single variable function using interp1, but I do...

3 years ago | 1 answer | 0

### 1

answerQuestion

Empirical source terms with PDEPE

Suppose I'm solving an equation: ...

3 years ago | 1 answer | 0

### 1

answerQuestion

How do I include a user specified hessian function for fmincon?

I am working on an optimisation code and I have a Hessian function I wish fmincon to use. I'm currently having trouble trying to...

3 years ago | 1 answer | 0

### 1

answerIs it possible to store the intermediate values of fmincon?

So I had to do a lot of searching and turns out that this is possible without downloading code. The key was to use 'OutputFcn' i...

3 years ago | 0

| accepted

Question

Is it possible to store the intermediate values of fmincon?

If I'm runnning fmincon, and I want to see the values of the parameters at each iteration, is there a way to do this? The docum...

3 years ago | 5 answers | 0

### 5

answersQuestion

Defining a stopping criterion for fmincon

I am looking at an optimisation problem with the following objective function: ...

3 years ago | 1 answer | 0

### 1

answerQuestion

Objective function doesn't converge but jumps around

I have been trying to complete an optimisation problem. I am looking at radial heat diffusion on a cylinder. I want to tackle it...

3 years ago | 0 answers | 0

### 0

answersQuestion

Crank Nicholson method for cylindrical co-ordinates

I am trying to solve the heat equation in cylindrical co-ordinates using the Crank-Nicholson method, the basic equation along wi...

3 years ago | 0 answers | 0

### 0

answersQuestion

Converting anonymous function to a matrix

I have a function of the form: , which I want to evaluate. I could do this old school with a double loop but that would take t...

3 years ago | 1 answer | 0

### 1

answerQuestion

Diagonal matrices with spdiags

I'm working on a numerical solution to an equation and as part of this I have to solve a matrix solution. The system of equation...

3 years ago | 1 answer | 0

### 1

answerQuestion

Is there a way of removing these for loops to speed up my code?

I have the analytical solution to the following PDE: with boundary condition and and initial condition in the form of a Gr...

3 years ago | 1 answer | 0

### 1

answerQuestion

I have: Error using bsxfun Non-singleton dimensions of the two input arrays must match each other.

So I have some code which I want to get working and I don't understand the error which is being given to me which is: Error usin...

3 years ago | 2 answers | 0

### 2

answersQuestion

Interp1 returns NaN for a value

I have some data (x,f(x)) where 0<=x<=1 and I have N points. I wish to obtain f for an inteverval [a,b] which is well within the...

3 years ago | 1 answer | 1

### 1

answerQuestion

Tracking the size of a variable

Hi, I have a vector of length 200. When I run my program it somehow halfs in length, and I have no idea why. Is there a way of ...

4 years ago | 1 answer | 0

### 1

answerNot enough input arguments when doing global optinisation

I've seen what I need to do. The set up of the function is different to lsqcurvefit: I had to define the function as: fun = ...

4 years ago | 0

Question

Not enough input arguments when doing global optinisation

I am trying to use the global optimisation toolbox to find some parameters which will make a computed curve overlay some experim...

4 years ago | 1 answer | 0

### 1

answerQuestion

lsqcurvefit doesn't curve fit

I have a model which I want to paramtrise using lsqcurvefit. I have 10 parameters that I must find and I have 10 pieces of data ...

4 years ago | 2 answers | 0