Creating Curve from Moving Point

I want to create curves based on moving points P6 and P7. Here is what I have so far. Can someone please tell me how I can create a curve that could be used to calculate the area between two points?

hold on

axis ([-20 20 -20 20])
axis off

P1=[-11,0];
P2=[-1,0];
h{1}=plot([P1(1) P2(1)],[P1(2) P2(2)],'LineWidth',5,'Color','black');    

x=5*pi/8;
b=0:pi/40:x;

P6vct=nan(numel(b),2)
P7vct=nan(numel(b),2);

for k=1:numel(b)

    Z=[4,0];
    h{2}=viscircles(Z,5,'LineWidth',2,'LineStyle','--','Color','black');

    A=[0,0];
    h{3} = viscircles(A,1,'LineWidth',2,'Color','black'); 
    PA=A+[cos(b(k)-(pi)),sin(b(k)-(pi))];
    h{4}=viscircles(PA,.1,'Color','black');
    
    B = [4-4*cos(2*asin(.25)),-4*sin(2*asin(.25))];
    h{5} = viscircles(B,1,'LineWidth',2,'Color','green');
    PB=B+[cos(-b(k)-(pi/2)),sin(-b(k)-(pi/2))];
    h{6}=viscircles(PB,.1,'Color','green');
    
    C = [4-4*cos(4*asin(.25)),-4*sin(4*asin(.25))];
    h{7} = viscircles(C,1,'LineWidth',2,'Color','blue');
    PC=C+[cos(b(k)-(pi/2)),sin(b(k)-(pi/2))];
    h{8}=viscircles(PC,.1,'Color','blue');
    
    D = [4-4*cos(6*asin(.25)),-4*sin(6*asin(.25))];
    h{9} = viscircles(D,1,'LineWidth',2,'Color','red');
    PD=D+[cos(-b(k)-(pi/2)),sin(-b(k)-(pi/2))];
    h{10}=viscircles(PD,.1,'Color','red');
    
    E = [4-4*cos(8*asin(.25)),-4*sin(8*asin(.25))];
    h{11} = viscircles(E,1,'LineWidth',2,'Color','yellow');
    PE=E+[cos(b(k)-(pi/2)),sin(b(k)-(pi/2))];
    h{12}=viscircles(PE,.1,'Color','yellow');
    
    P3=B+[cos(b(k)),sin(b(k))];
    P4=C+[cos(b(k)),sin(b(k))];
    P5=D+[cos(b(k)),sin(b(k))];
    P6=E+[cos(b(k)-x),sin(b(k)-x)];
    P7=E+[11*cos(b(k)-x),11*sin(b(k)-x)];
    
    P6vct(k,:)=P6;
    P7vct(k,:)=P7;
    
    h{13} = plot([P6(1) P7(1)],[P6(2) P7(2)],'LineWidth',5,'Color','black');
    %h{14}=plot(P6vct(:,1),P6vct(:,2),'LineWidth',3,'Color','black');
    curve1=[P6vct(:,1),P6vct(:,2)];
    curve2=[P7vct(:,1),P7vct(:,2)];
    %h{15}=plot(curve2,'LineWidth',3,'Color','black');
    
    drawnow();
    pause(0.001);
    if k<numel(b)
    delete(vertcat(h{2:13}));
    end
    
    area(curve1)
    fill(curve1,curve2,'blue');
    str = {'Area Swept:'};
    annotation('textbox',[0.2 0.5 0.3 0.3],'String',str,'FitBoxToText','on');
end
hold off

axis ([-20 20 -20 20])
axis off

[KSSV]

This is not the full ocde...give the full code with all variables defined.

[Allison Bushman]

I've fixed it so my whole code is provided.

Answer 1

[KSSV]

hold on
axis ([-20 20 -20 20])
axis off
P1=[-11,0];
P2=[-1,0];
h{1}=plot([P1(1) P2(1)],[P1(2) P2(2)],'LineWidth',5,'Color','black');
x=5*pi/8;
b=0:pi/40:x;
P6vct=nan(numel(b),2)
P7vct=nan(numel(b),2);
cP6 = zeros([],2) ;
cP7 = zeros([],2) ;
for k=1:numel(b)
    Z=[4,0];
    h{2}=viscircles(Z,5,'LineWidth',2,'LineStyle','--','Color','black');
    A=[0,0];
    h{3} = viscircles(A,1,'LineWidth',2,'Color','black');
    PA=A+[cos(b(k)-(pi)),sin(b(k)-(pi))];
    h{4}=viscircles(PA,.1,'Color','black');
    
    B = [4-4*cos(2*asin(.25)),-4*sin(2*asin(.25))];
    h{5} = viscircles(B,1,'LineWidth',2,'Color','green');
    PB=B+[cos(-b(k)-(pi/2)),sin(-b(k)-(pi/2))];
    h{6}=viscircles(PB,.1,'Color','green');
    
    C = [4-4*cos(4*asin(.25)),-4*sin(4*asin(.25))];
    h{7} = viscircles(C,1,'LineWidth',2,'Color','blue');
    PC=C+[cos(b(k)-(pi/2)),sin(b(k)-(pi/2))];
    h{8}=viscircles(PC,.1,'Color','blue');
    
    D = [4-4*cos(6*asin(.25)),-4*sin(6*asin(.25))];
    h{9} = viscircles(D,1,'LineWidth',2,'Color','red');
    PD=D+[cos(-b(k)-(pi/2)),sin(-b(k)-(pi/2))];
    h{10}=viscircles(PD,.1,'Color','red');
    
    E = [4-4*cos(8*asin(.25)),-4*sin(8*asin(.25))];
    h{11} = viscircles(E,1,'LineWidth',2,'Color','yellow');
    PE=E+[cos(b(k)-(pi/2)),sin(b(k)-(pi/2))];
    h{12}=viscircles(PE,.1,'Color','yellow');
    
    P3=B+[cos(b(k)),sin(b(k))];
    P4=C+[cos(b(k)),sin(b(k))];
    P5=D+[cos(b(k)),sin(b(k))];
    P6=E+[cos(b(k)-x),sin(b(k)-x)];
    P7=E+[11*cos(b(k)-x),11*sin(b(k)-x)];   
    P6vct(k,:)=P6;
    P7vct(k,:)=P7;
    
    cP6(k,:) = P6 ;
    cP7(k,:) = P7 ;
    
    h{13} = plot([P6(1) P7(1)],[P6(2) P7(2)],'LineWidth',5,'Color','black');
    %h{14}=plot(P6vct(:,1),P6vct(:,2),'LineWidth',3,'Color','black');
    curve1=[P6vct(:,1),P6vct(:,2)];
    curve2=[P7vct(:,1),P7vct(:,2)];
    %h{15}=plot(curve2,'LineWidth',3,'Color','black');
    
    drawnow();
    pause(0.001);
    if k<numel(b)
        delete(vertcat(h{2:13}));
    end
    
    area(curve1)
    fill(curve1,curve2,'blue');
    str = {'Area Swept:'};
    annotation('textbox',[0.2 0.5 0.3 0.3],'String',str,'FitBoxToText','on');
end
plot(cP6(:,1),cP6(:,2),'r')
plot(cP7(:,1),cP7(:,2),'b')
hold off
axis ([-20 20 -20 20])
axis off

[Allison Bushman]

How would I fill the area between cP6 and cP7?

[KSSV]

Read about patch

patch(cP7(:,1),cP7(:,2),'r')

[Allison Bushman]

This is somewhat working, but it is making two separate semicircles and not filling the area between the two curves.

[KSSV]

Combine bot the curve sinto one an duse patch.

[Allison Bushman]

I am not sure how to do this. This is the code that I have now.

patch([cP7(:,1) cP7(:,2)],[cP6(:,1) cP6(:,2)],'r','FaceAlpha',.3);