MATLAB: Help with for loops

for loopsMATLAB

I'm really new to MATLAB so I apologise in advance for my simple question. But I'm trying to construct a plot of 5 different sine waves, & my code looks like this: 
x=0:pi/100:2*pi;
y1=sin(x);
plot(x,y1);
hold on
y2=sin(2*x);
plot(x,y2)
y3=sin(3*x);
plot(x,y3)
y4=sin(4*x);
plot(x,y4)
y5=sin(5*x);
plot(x,y5)
I'd like to learn how to tidy this up a bit by using a loop in place of manually adding each next sine wave, but I can't figure out how for the life of me, & would really appreciate some help or advice.

Best Answer

Here are three options in order of best-practice. They all produce the same plot. Feel free to ask any follow-up questions. 
%% Option 1: don't use a loop at all
x = 0 : pi/100 : 2*pi;         % produce your x-data (vector)
w = 1:5;                       % these are your factors (vector)
y = sin(w' * x);               % produce your y data; note the transpose (') (matrix)
plot(x,y)                      % Plot the data
%% Option 2: collect data within loop, then plot it. 
x = 0 : pi/100 : 2*pi;         
w = 1:5; 
yMat = zeros(length(x), length(w));     %produce an empty matrix where we'll store loop data
for i = 1:length(w)                     %Loop through each factor
    yMat(:,i) = sin(w(i) * x);          %store the y-data
end
plot(x, yMat)                          
%% Option 3: plot data within loop
x = 0 : pi/100 : 2*pi; 
w = 1:5; 
figure; 
axh = axes;                             %create the empty axes
hold(axh, 'on')                         %hold the axes
for i = 1:length(w)
    y = sin(w(i) * x);                  % produce temporary y-data
    plot(axh, x,y)                      % plot the single line
end
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