How do I plot a horizontal line

s=0.5:0.001:1;
f=yline(0.25);
plot(s,f)

How do I get this to produce a horizontal line at y=0.25 for the interval 0.5 <= s <= 1? Every time I run the script I get a blank graph.

Thanks

Answer 1

[KSSV]

s=0.5:0.001:1;
f=repmat(0.25,1,length(s));
plot(s,f)

Answer 2

[madhan ravi]

Using plot here is pointless when you can directly:

yline(.25)
xlim([.5,1])