Plot many curves in one plot using for loop

Is there a way to have the variables in the plot change?

I am trying to do this:

for i=1:1:8
plot(x(i),o_vac(i))
hold on
end

But I get a grey screen for my figure. I want to plot 8 graphs with x1, y1, then x2, y2. Is this possible?

[Stephen23]

plot(x(i),o_vac(i))

does not make much sense: you are plotting single points in a loop. This is very inefficient: if that is what you want then just plot all points at once and select the linestyle to suit.

Why do you need to use a loop? Just put your data into a matrix (arranged by column) and one single plot call is all you need:

plot(X,Y)

[Benjamin Cowen]

They are not suppose to be single points. I read in the data as shown below. I just have many of these, and don't want to write it all out

data1 = xlsread('C:\Users\Ben\examples.xlsx','PKA1');
x1 = data1(:,1);
o_vac1 = data1(:,4);

Answer 1

[Robert U]

Hi Benjamin,

the following code snippet works as you would expect it to do:

    % create data
    for ik = 1:4
        x(:,ik) = (-2:0.01:2)*pi/4*ik;
        A(:,ik) = sin(x(:,ik) + ik*pi/4);
    end

    % plot data
    fh = figure;
    ah = axes('Parent',fh);
    hold on

    for ik = 1:4
        plot(ah,x(:,ik),A(:,ik))
    end

My suggestion would be to check on data validity. Are all values numeric? Are there blank spaces (empty cells) or nan-values?

Kind regards,

Robert