MATLAB: Plotting grid of square points inside a circle of given radius

gridmatrix array

Hi,

I am trying to create a meshgrid of points using MATLAB which has circular aperture. I know that one can generate and X and Y grid of points in MATLAB and it can be square grid of rectangular grid depending on the number of points in X and Y coordinates. But how to draw a grid of points which is neither rectangular nor square, rather it is bounded by a 'circular aperture'.

I have tried to illustrate the concept in the picture.

Best Answer

I'd create your grid of points, define the points of your circle, then use inpolygon to identify just the points that are inside your circle, and use that to determine which points to plot.

Related Solutions

MATLAB: Get data within circular ROI

This code also works for non-integer positions and radii.

data=rand(200,200); %generate example data
radius = 20; %circle radius
centre = [100,100]; %circle centre
[X,Y]=ndgrid(1:size(data,1),1:size(data,2));
X=X-centre(1);Y=Y-centre(2);%shift coordinate grid
L=sqrt(X.^2+Y.^2)<=radius;
data_within_circle = data(L);

MATLAB: Finding number of points inside a circle and assign them into a matrix

one way to do it:

clc;clear
xy = rand(100,2);
plot(xy(:,1),xy(:,2),'b.')
hold on
t = linspace(0,2*pi);
plot(.5+.25*cos(t),.5+.25*sin(t),'r-')
axis square
r = hypot(xy(:,1)-.5,xy(:,2)-.5);
plot(xy(r<=.25,1),xy(r<=.25,2),'go')

Best Answer

Related Solutions

MATLAB: Get data within circular ROI

MATLAB: Finding number of points inside a circle and assign them into a matrix

Related Question