A basic plotting problem in a for loop

Hello everybody,

I have a Problem which seems to be very stupid and I apologize for my question in advance!

I have a for loop to plot all of the results of a former loop. Now I would like to change the color of the plots to grey. Basically this is not a big deal if you have x and y for example. In my case I plot data1 vs data2. Both of them have the same size. If I use a colormap or something like 'color', [1 1 1] I always get the error that the vectors must be the same size. How can I fix this?!

for d=1:numel(Filename)
    figure(1);
    hold on
    plot(Data_1(:,d), Data_2(:,d), 'Color', [1 1 1])
    axis([-25 25 -20 25])
    axis equal
end

Thank you!

Cheers

Christian

[Adam]

Are you sure that Data_1(:,d) and Data_2(:,d) are the same size?

Because using 'Color' like that as a name-value pair should not give you this error.

[Stephen23]

@Christian: please edit your question and give us the complete error message. This means all of the red text.

[Christian]

Hey Adam and Stephan,

yes, the vectors are exactly the same size. It works now, I think there was a Syntax error somewhere :)

Answer 1

[tafteh]

Hi Christian,

(a) "(There's) no such thing as a stupid question," read more at link !

(b) Unless the vectors Data_1(:,d) and Data_2(:,d) are not the same size, you should not get an error.

(c) using the argument 'Color' with the value of [1 1 1], results in plotting all the lines in white which is the same as the white background of plotting environment. You may want to change that :)

(d) I wrote the following code trying to mimic what you want to do:

first I generate two 2d matrices, a and b with same size:

if true
  a = rand(3, 4); b = rand(3, 4);
end

and then I use your code to plot them:

if true
      for d=1:size(a, 2) % mimic the numel(Filename) in your code.
          figure(1);
          hold on
          plot(a(:,d), b(:,d), 'Color', [.1 .1 .1])
          axis([-25 25 -20 25])
          axis equal
      end
end

it works for me. You may want to change the code based on your need.

cheers,

[Christian]

Thank you very very much! Now it works!

Even though I do not know, what was my fault, maybe just a Syntax issue.