Clear Filters
Clear Filters

choose random places on matrix

7 views (last 30 days)
omer
omer on 30 Aug 2024
Edited: Image Analyst on 30 Aug 2024
i need to create a game of maze on matlab. i have zero matrix mXm and i need to insert to the matrix n places which will mark as obsticals, how can i choose n random places on matrix and replace the zeros to 1? (randomly)

Answers (2)

arushi
arushi on 30 Aug 2024
Hi Omer,
  • randperm: This function generates a random permutation of integers from 1 to totalElements, ensuring that the selected indices for obstacles are unique.
Here is an example :
function maze = createMaze(m, n)
% Check if the number of obstacles is less than or equal to total matrix elements
if n > m * m
error('Number of obstacles cannot exceed the total number of matrix elements.');
end
% Initialize the m x m matrix with zeros
maze = zeros(m, m);
% Generate n unique random indices for obstacles
totalElements = m * m;
randomIndices = randperm(totalElements, n);
% Convert linear indices to row and column subscripts
[rowIndices, colIndices] = ind2sub([m, m], randomIndices);
% Place obstacles in the matrix
for i = 1:n
maze(rowIndices(i), colIndices(i)) = 1;
end
end
Hope this helps.

Image Analyst
Image Analyst on 30 Aug 2024
Edited: Image Analyst on 30 Aug 2024
Simply use randperm and linear indexing. No need to figure out or convert locations to (row, column) indexes (that's a waste of time).
m = 7; % Width and height of maze
maze = false(m, m); % Initialize maze to all zeros. Use logical type to save memory space.
numOnes = round(0.3 * m * m); % 30% of locations will be 1's.
randomLocations = randperm(m * m, numOnes); % Get all locations in a random order.
maze(randomLocations) = 1 % Assign a 1 to those locations.
maze = 7x7 logical array
0 0 1 0 0 0 0 0 0 1 0 1 0 0 1 1 0 0 0 0 0 0 0 0 1 0 1 0 0 0 1 0 0 1 0 0 1 1 0 0 1 0 0 1 1 1 0 0 0

Products


Release

R2024a

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!