% This m-file animates the static solution to a simply supported beam with
% a load P moving from the left end to the right end.
% This m-file was written at the University of Wyoming in the Electrical
% and Computer Engineering Department and is to be distributed without
% cost.
clear all
set(0,'DefaultAxesFontSize',12);
set(0,'DefaultTextFontSize',12);
x1overL=linspace(0,1.3,131);
xoverL=linspace(0,1,101);
%V=[1 zeros(1,100)];
%M=[zeros(1,101)];
V=[1 zeros(1,100)];
M=[zeros(1,101)];
for k=2:100
    V1=[ones(1,k)*(1-x1overL(1,k)) -x1overL(1,k)*(ones(1,101-k)) ];
    V=[V;V1];
    M1=[(1-x1overL(1,k))*xoverL(1,1:k)];
    M2=[x1overL(1,k)*(ones(1,101-k)-xoverL(1,k+1:101))];
    M=[M;M1 M2]; 
    end
V=[V;zeros(1,101)];
M=[M;zeros(1,101)];
xarrow=[0 0 .02 -.02 0];
yarrow=[1 .01 .05 .05 .01];

figure(1);clf;
axis([-.1 1.1 -.1 1.4])
hold on
xlabel('Dimensionless Distance, x/L');
hold on
ylabel('Dimensionless Load, Load/P');
hold on
plot(xoverL,zeros(1,101),'LineWidth',[2.5],'Color','k');
hold on
plot([-.1 0],[0 0],'k');
hold on
plot([1 1.1],[0 0],'k');
hold on
plot([0 1],[0 0],'o')
hold on
a1=plot(x1overL(1,1)*ones(1,5)+xarrow,yarrow,'EraseMode','xor','LineWidth',[2]);
%a2=plot((xoverL(1,1)-.3)*ones(1,5),yarrow,'EraseMode','xor');
t5=text(.6,1.2,'Press Enter to Continue');
pause
set(t5,'String','                       ')
for k=1:101
    set(a1,'Xdata',x1overL(1,k)*ones(1,5)+xarrow);
    %set(a2,'Xdata',(x1overL(1,k)-.3)*ones(1,5)+xarrow);
    pause(.06)
end
set(t5,'String','Press Enter to Continue')
pause

figure(2);clf;
axis([-.1 1.1 -2.1 2.1]);
hold on
xlabel('Dimensionless Distance, x/L');
hold on
ylabel('Dimensionless Shear, V/P');
hold on
plot([-.1 1.1],[0 0],'k');
shear=plot(xoverL,V(1,:),'EraseMode','xor');
t1=text(.6,1.6,'Press Enter to Continue');
pause
plot([-.1 1.1],[0 0],'k');
hold on
for k=1:101
    set(shear,'Ydata',V(k,:));
    pause(0.06)
end
plot([-.1 1.1],[0 0],'k');
box on
plot([-.1 1.1],[0 0],'k');
set(t1,'String','Press Enter to Continue')
pause

figure(3);clf;
axis([-.1 1.1 -.1 .3]);
hold on
xlabel('Dimensionless Distance, x/L');
hold on
ylabel('Dimensionless Moment, M/PL');
hold on
plot([-.1 1.1],[0 0],'k');
moment=plot(xoverL,M(1,:),'EraseMode','xor');
t1=text(.6,.25,'Press Enter to Continue');
pause
for k=1:101
    set(moment,'Ydata',M(k,:));
    pause(0.06)
end
plot([-.1 1.1],[0 0],'k');
box on
set(t1,'String','Press Enter to Continue')
pause

%calculate slope and deflection
yprime=[zeros(1,101)];
for k=2:101
    yprime1=zeros(1,101);
    for i=1:101
        yprime1(1,i)=(sum(M(k,1:i))-(M(k,i)/2))*.01;
    end
    yprime=[yprime;yprime1];
end

%calculate deflection
y=zeros(1,101);
for k=2:101
    y1=zeros(1,101);
    for i=1:101
        y1(1,i)=(sum(yprime(k,1:i))-(yprime(k,i)/2))*.01;
    end
    y1=-(y1-y1(1,101)*xoverL);
    y=[y;y1];
end

figure(5);clf;
yarrow=-[.008 .0005 .001 .001 .0005];
axes('Ydir','reverse')
hold on
axis([-.1 1.1 -.01 .025]);
hold on
xlabel('Dimensionless Distance, x/L');
hold on
ylabel('Dimensionless Deflection, y(x)EI/PL^3');
hold on
plot([-.1 0],[0 0]);
hold on
plot([1 1.1],[0 0]);
hold on
plot([0 1],[0 0],'o')
hold on
deflection=plot(xoverL,y(1,:),'EraseMode','xor','LineWidth',[3]);
a3=plot(xarrow,yarrow,'LineWidth',[2],'Color','k','EraseMode','xor');
t1=text(.6,-.005,'Press Enter to Continue');
pause
plot([-.1 1.1],[0 0],'k');
hold on
for k=2:101
    set(deflection,'Ydata',y(k,:));
    set(a3,'Xdata',xarrow+xoverL(1,k),'Ydata',yarrow+y(k,k));
    pause(0.06)
end
plot([-.1 1.1],[0 0],'k');
hold on
box on
set(t1,'String','Press Enter to Continue')
pause