MATLAB is not plotting my constant value plot. Why so?

clc
close all
clear
bw=100e3;
FS=2e-9;
IBQN_dBFS=-76.1;
P_IBN=(10^(IBQN_dBFS/10))*(0.5*((FS/2)^2));
PSDnin1=sqrt((P_IBN)/(bw));
figure(1)
plot(linspace(0,bw,10),PSDnin1)
% loglog(linspace(0,bw,10),PSDnin1)
xlabel('Frequency(Hz)')
ylabel('PSDin(A2/Hz)')
axis auto

This is my matlab code and i would like to plot the constant value of PSDnin = 3.5e-15 as a constant line from 0 to bw. I get an empty graph.

Is it plotting and I am unale to see?

Is it because of the lower value? I tried the loglog plot. But it doesnt help. Please help me to resolve the issue.

Answer 1

[Jan]

The code does draw some points. You see them, if you use a marker:

plot(linspace(0,bw,10), PSDnin1, 'o')

or with a line:

plot(linspace(0,bw,10), repmat(PSDnin1, 1, 10))

The documentation of plot mentions:

If one of X or Y is a scalar and the other is either a scalar or a vector, then the plot function plots discrete points. However, to see the points you must specify a marker symbol, for example, plot(X,Y,'o').

[Jaikrishnan Mahalekshmi Sahasranamam]

Hey Jan,

Yes that worked. Great!!.

This one also worked giving a straight line

semilogy([0,bw],[PSDnin1,PSDnin1])

or

plot([0,bw],[PSDnin1,PSDnin1])

Thanks a lot