MATLAB: Creating a Helix Spiral

Question

I want to create a helix sprial. I wish to have control over changing the radius of the spiral, the gap between each layer and the height of the spiral. How would I do that?

I obtained the code below from MATLAB's Documentation however I am not familiar with it. If you can explain how st and ct works that would be helpful too.

Thanks in advance

clc; clear; close all
t = 0:pi/50:10*pi;
st = sin(t);
ct = cos(t);
plot3(st,ct,t)
grid on

Answer 1

r = ...
gap = ...
t = (2*pi/gap)*(0:0.001:10);
st = r*sin(t);
ct = r*cos(t);