(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Hello, I have this project due for next Friday. I need help. Its on diffusion limited aggregation. A topic which is unfamiliar to me. I know exactly how to do the problem, but I don't know how to code it correctly. Basically I allow a seed particle to be in a location in a 9 x 9 matrix. Another particle is put into this matrix with a random location. basically just have to show that my code gives an image like the usual fractal images.

2. Relevant equations

None.

3. The attempt at a solution

Here's my code for the random walk;

Is that the correct coding for a random walk and how would I bring the actual dla into this problem. Thanks for anyone's help. It will be greatly appreciated as i'm freaking out and I know that I won't be able to do this. % Daniel Lordan_108576939_ComputationalProject_MinimumGoal

clear all % clears all variables

xD = 0; % Holds vector of the previous values x has taken

yD = 0; % Holds vector of the previous values y has taken

rD = 0; % Used when calculating the distance form origin

x_position = 0; % Start position at origin

y_position = 0; % Start position at origin

num_steps = 2000;

n = 9;

% Sets n equal to nine

xx = round(rand(n));

% creates a 9 x 9 array of zeros or ones ie creates an array of random

% numbers between 0 and 1

% this is just to generate some data for a 2-D "top-view" plot,

colormap([0 0 0;1 1 1])

% creates a colormap of black and white

imagesc(xx)

% plots the matrix xx as an image

axis square

% makes the plot square, as opposed to the usual rectangle

save(['E:\Matlab Project\matrix_xx.txt'], 'xx', '-ASCII','-TABS')

% save the content of xx into a txt file

perm_col = randperm(4);

% this generates a column vector containing a random permutation of the

% integers from 1 to 4

dir_mov = perm_col(1);

% the first element of perm_col will be a random number between 1 and 4

% and could be used to determine the direction of the next random walk step

for ctr = 1:(num_steps-1)

direction = randperm(4); % Direction is chossen randomly from numers 1, 2, 3, 4

if direction(1) == 1

x_position = x_position + 1; % Go East

elseif direction(1) == 2

x_position = x_position -1; % Go West

elseif direction(1) == 3

y_position = y_position + 1; % Go North

elseif direction(1) == 4

y_position = y_position -1; % Go South

end

end

plot(xD, yD)

hold on

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# Homework Help: Diffusion Limited Aggregation Matlab Problem

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