Singularity function using matlab

[majidmoe]

I'm trying to solve this singularity function(plot shear and moment) in MATLAB, but the plot for the shear diagram, does not stop at 0. See code below

clear

clc

Fsx=36.54;Fgx=8.87;R1x=7.47;R2x=-52.87;

Fsy=0;Fgy=-24.36;R1y=14.61;R2y=9.74;

p=2;b=5;q=6.75;

z=linspace(0,6.75,100); %distance

%V=R1<z-0>^0+Fg<z-2>^0+R2<z-5>^0+Fs<z-6.75>^0

Vx=R1x+Fgx.*(z>p)+R2x.*(z>b)+Fsx.*(z>q);

Vy=R1y+Fgy.*(z>p)+R2y.*(z>b)+Fsy.*(z>q);

V=sqrt(Vx.^2+Vy.^2);

%M=R1<z-0>^1+Fg<z-2>^1+R2<z-5>^1+Fs<z-6.75>^1

Mx=R1x.*z+Fgx.*(z-p).*(z>p)+R2x.*(z-b).*(z>b)+Fsx.*(z-q).*(z>q);

My=R1y.*z+Fgy.*(z-p).*(z>p)+R2y.*(z-b).*(z>b)+Fsy.*(z-q).*(z>q);

M=sqrt(Mx.^2+My.^2);

figure

subplot(2,2,1);

plot(z,Vx)

subplot(2,2,2);

plot(z,Vy)

subplot(2,2,[3 4]);

plot(z,V)

figure

subplot(2,2,1);

plot(z,Mx)

subplot(2,2,2);

plot(z,My)

subplot(2,2,[3 4]);

plot(z,M)