MATLAB: Example of linecirc function

linecirc

can anyone please show me an example of linecirc function

Best Answer

Hi Manoj,

linecirc gives the intersection points of a line and a circle.

Syntax:

[xout,yout] = linecirc(slope,intercpt,centerx,centery,radius);

This function finds the points of intersection given a circle defined by a center and radius in x-y coordinates, and a line defined by slope and y-intercept, or a slope of “inf” and an x-intercept. Two points are returned. When the objects do not intersect, NaNs are returned.

When the line is tangent to the circle, two identical points are returned. All inputs must be scalars.

Example:

[xout, yout]  = linecirc(-1,3,0,0,5);

This will give the intersection point of line

and circle

Related Solutions

MATLAB: How to tell whether or not 5 or more lines intersect

After you generate the circle centers and their radii, you can run the following code to find the indices of the iterations that create less than 5 intersections.

% find each pair of circles which intersect with each other and store the information in matrix M
M = zeros(n);
for i=1:n-1
    for j=i+1:n
        if norm([x_pos(i)-x_pos(j),y_pos(i)-y_pos(j)])<rad(i)+rad(j) && norm([x_pos(i)-x_pos(j),y_pos(i)-y_pos(j)])>abs(rad(i)-rad(j))
            M(i,j)=1;
            M(j,i)=1;
        end
    end
end
% identify the iteration index which creates less than 5 intersections
index = zeros(n,1);
for i = 1:n
    ind = find(M(:,i)~=0);
    if ~isempty(ind)
        if length(ind)>=5
            continue;
        else
            M1 = M(ind,ind);
            if length(ind)+1/2*sum(sum(M1))>=5
                continue;
            else
                index(i)=1;
            end
        end
    end
end     
idx = find(index~=0);

The indices of the iterations which create less than 5 intersections are stored in the variable idx. Iterate on idx, and you can discard iterations that create 5 or more than 5 intersections.

MATLAB: Intersection between line and circle

Each circle with have either 0, 1, or 2 intersection points. Do you have the formula for each circle, meaning it's center coordinates and radius ? If seems like knowing the formulas for the lines you might be able to use fzero() to find the intersection point(s).

By the way, what toolbox is linecirc() in? I don't have it.

Best Answer

Related Solutions

MATLAB: How to tell whether or not 5 or more lines intersect

MATLAB: Intersection between line and circle

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