Does anyone know how to create colors?

Hello everyone,

How can I create/ have different colors from the standard ones (i.g. 'g','r','b','m'...)?

Thank you.

[Stephen23]

https://www.mathworks.com/matlabcentral/fileexchange/48155-convert-between-rgb-and-color-names

[Pul]

@Stephen Cobeldick Thank you!

Answer 1

[Bjorn Gustavsson]

Colours can be specified by rgb-values in a 1-by-3 array with values between zero and one. So for example:

light_blue = [0.5 0.5 1]; 
plot(0:12,randn(1,12),'color',light_blue)

HTH

[Pul]

It gives me error when I try it.

[Image Analyst]

Try

light_blue = [0.5 0.5 1]; 
plot(1:12,randn(1,12),'color',light_blue)

[Pul]

Now it works, thank you.

Last question: given that values have to be between zero and one, if I want to have another color (not shades of blue as in your example), what do I have to do?

Thanks.

[Bjorn Gustavsson]

That's as simple as:

red_I = 0.8;
green_I = 0.4;
blue_I = 0.2;
rgb_color = [red_I,green_I,blue_I];

That is first component red, second green and third blue intensities. From there it is easy to come up with the approximate values for the colour you want, but some adjustments to get what you really want is typically necessary...

[Pul]

Okay, got it.

Thank you.

[Bjorn Gustavsson]

@Image Analyst, I have a poor short-time memory - but that was a bit extreme even for me.

@Pul, Great. Have a look at the file exchange for color-manipulation-tools that might help you with more demanding color-designing work - always look there for tools that solve or nearly solve your problems (it has saved me many months of work)!

[Pul]

@Bjorn Gustavsson Okay, thank you!

Answer 2

[Image Analyst]

Try this:

% Create 20 different colors according to the jet color map.
colors = jet(20);
% Plot randome data, each curve with one of the colors we created.
% Basically you have to get the color equal to one row from colors.
for k = 1 : size(colors, 1)
	thisColor = colors(k, :);
	y = rand(1, 5) + 2 * k; % Create some random data.
	plot(y, '.-', 'Color', thisColor, 'LineWidth', 4, 'MarkerSize', 50); % Plot this one curve.
	hold on; % Don't let subsequent plots blow away this one we just drew.
end
grid on;
xlabel('X');
ylabel('Y');

[Pul]

Thank you!

But how can I choose the color I want to plot among them?

[Image Analyst]

@Pul, like @Bjorn Gustavsson said, if you have some specific color you want to use, then you can do

light_blue = [0.5 0.5 1]; 
plot(1:12, randn(1,12), 'color', light_blue)

If you have created a list of lots of colors, like in my example, and, for example, you want to make the curve with the 10th color from the list, you can do

plot(y, '.-', 'Color', colors(10, :), 'LineWidth', 4, 'MarkerSize', 50); % Plot this one curve.

My demo showed that, where I plotted every color from k=1 to k=20.

[Pul]

@Image Analyst Yes, clear, I got it.

Thank you!