Plotting a sine wave going wrong

So I am trying to plot a simple sine wave, and I used the code recommended here.

% Constants
fs = 8000;              % Sample rate (Hz)
duration = 1;           % Duration of the signal (seconds)
frequency = 3000;       % Frequency of the sine wave (Hz)

% Time vector
t = 0:1/fs:duration-1/fs;

% Generate the sine wave
x = sin(2*pi*frequency*t);

% Plot the sine wave
plot(t, x);
xlabel('Time (s)');
ylabel('Amplitude');
title('Sine Wave');

But it is a very weird plot. Why is that happening?

Here's the full plot for reference:

Answer 1

[Ishit]

Hi Bhargava,

This is beacuse of high frequency.

Increasing the frequency of a sine plot leads to a higher number of oscillations. And thus these lines seems to overlap.

In figure below you can observe as term inside of sin increases, the period decreases.

Credits: https://www.quora.com

Answer 2

[Image Analyst]

You're plotting so many cycles that the blue curves all overlap and make the plot solid. Either plot fewer points, or use the zoom tool to zoom way in.