% infin.m  96/08/12
%
%
% Plot of infinitesimal portion of space curve
%

    axis([-.5 2 -.5 2]);
    v1=[.5; .5];
    v2=[1.5; 1.5];
    colp='r-';
    circ='ro';
    plot([v1(1) v2(1)], [v1(2) v2(2)],colp);
    hold on;
    plot(v1(1),v1(2),circ);
%    plot(v2(1),v2(2),circ);
    plot([v1(1) v2(1)], [v1(2) v2(2)],colp);
    arrow2(v2-[.001;.001],v2,.1,colp);

    f1=[.5; .5];
    f2=[.5; 1.5]; 
    arrow2(f1,f2,.1,'w-'); 
    axis([-.5 2 -.5 2]);
    axis square;
    plot([0 0],[-.5 2],'w-');
    plot([-.5 2],[0 0],'w-');

    text(.4,.3,'r(t)');
    text(1.4,1.3,'r(t+dt)');
    text(-.1,1,'F(x(t),y(t))');
    text(1.5,-.2,'x');
    text(-.2,1.5,'y');
    text(1,.8,'D=r''(t)dt');

    hold off;
