Visualization of Fourier series expansion of Triangular wave (MATLAB)

CODE:

figure
pause(2);
w=1;
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=1;
y=asin(nt);
z=(a/2)+y;
plot(t,z);
pause(2);
clf
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=3;
for i=1:2:n
y=y+a((-1)^((i-1)/2))(1/(i.^2))sin(iwt);
i=i+1;
end
z=(a/2)+y;
plot(t,z);
pause(2);
clf
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=5;
for i=1:2:n
y=y+a((-1)^{((i-1)/2))*(1/(i.}2))sin(iwt);
i=i+1;
end
z=(a/2)+y;
plot(t,z);
pause(2);
clf
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=11;
for i=1:2:n
y=y+a((-1)^{((i-1)/2))*(1/(i.}2))sin(iwt);
i=i+1;
end
z=(a/2)+y;
plot(t,z);
pause(2);
clf
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=21;
for i=1:2:n
y=y+a((-1)^{((i-1)/2))*(1/(i.}2))sin(iwt);
i=i+1;
end
z=(a/2)+y;
plot(t,z);
pause(2);
clf
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=51;
for i=1:2:n
y=y+a((-1)^{((i-1)/2))*(1/(i.}2))sin(iwt);
i=i+1;
end
z=(a/2)+y;
plot(t,z);
pause(2);
clf;
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=101;
for i=1:2:n
y=y+a((-1)^{((i-1)/2))*(1/(i.}2))sin(iwt);
i=i+1;
end
z=(a/2)+y;
plot(t,z);
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=501;
for i=1:2:n
y=y+a((-1)^{((i-1)/2))*(1/(i.}2))sin(iwt);
i=i+1;
end
z=(a/2)+y;
plot(t,z);
pause(2);
clf
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=1001;
for i=1:2:n
y=y+a((-1)^{((i-1)/2))*(1/(i.}2))sin(iwt);
i=i+1;
end
z=(a/2)+y;
plot(t,z);
t=0:0.01:2pi;
A=2pi;
a=1/(pi);
y=0;
n=20001;
for i=1:2:n
y=y+a((-1)^{((i-1)/2))*(1/(i.}2))sin(iw*t);
i=i+1;
end
z=(a/2)+y;
plot(t,z);