# how to do plotting with different colors in same figure?

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Ved on 6 Nov 2013
Answered: Da Bu on 22 Apr 2021
My sample code is this:
x=[1:100];
for i=1:5
y(:,i)=i*log(x);
end
This plots 5 different curves of same color.
How to plot each curve with a different color ?
##### 2 CommentsShowHide 1 older comment
Image Analyst on 2 Mar 2017
This is not a comment so you should put it with the rest of the "Answers" below (so you could get "reputation points" for it if someone "Votes" for it).

Simon on 6 Nov 2013
Hi!
If you plot like
plot(x,y)
and y is a matrix, you get plots with different color automatically. But you can do something like this to get manual coloring:
colorstring = 'kbgry';
figure(1); cla;
hold on
for i = 1:5
plot(x,y(:, i), 'Color', colorstring(i))
end
Simon on 11 Nov 2013
Hi!
Of course you have to define a usable colorspec. Take a look at http://en.wikipedia.org/wiki/RAL_colour_standard and follow the links there. There are many colors with their RGB values. Mind that matlab uses RGB values between 0 and 1, and not between 0 and 255!

Kelly Kearney on 6 Nov 2013
Also, using colormaps and set with multiple handles + cell arrays can be helpful if you need a lot of colors.
x = 1:100;
ii = (1:20)';
y = ii*log(x);
h = plot(x,y);
set(h, {'color'}, num2cell(jet(length(ii)), 2));
Saksham Gakhar on 19 Apr 2021
thank you!

Image Analyst on 6 Nov 2013
Simon showed you how to specify custom colors for each curve. If you want to know how to change the default color order, see my demo attached below.
Ved on 10 Nov 2013
thank you Image Analyst.

PeopleMATLAB on 13 Oct 2016
colormap jet;
cmap=colormap;
for i=1:5
Plot_color=cmap(i/5,:);
plot(x, y(i,:), 'Color', Plot_color);
hold on;
end
hold off;
##### 2 CommentsShowHide 1 older comment
C S on 11 Jul 2018
just use i*5 and you are okay

farhat khan on 19 Jul 2019
gys i have a question ..... how to detect the object with color based detection if the required object have more then one color e.g green and black ..........
Image Analyst on 19 Jul 2019
I don't beleive you can plot a single set of data with two colors and one call to plot (plotyy notwithstanding). You have to keep track of the handle of the things you plotted:
hGreen = plot(x1, y1, 'g-'); % Plot a green line.
hBlack = plot(x2, y2, 'k-'); % Plot a black line.
I'm not sure how you'd detect what the color was if you didn't save the handle to the colored line you plotted, but maybe there is a way by using findobj() and seeing if you can get the color of any line object as a property. It's certainly not as straightforward so I recommend you just save the handles to the colors of the lines you drew, if you plan to detect them later.

SYAHIRAH ZAKI on 7 Dec 2020
hi does anoyne know how to get different plot colors for each of my graph?
if i change the 'r' to 'g', i only get one color for each of my graph. I need each of my plot in different colour. please help me :( % Script file graph2.
% Several plots of the rational function y = x/(1+x^2)
% in the same window.
k = 0;
for n=1:3:10
n10 = 10*n;
x = linspace(-2,2,n10);
y = x./(1+x.^2);
k = k+1;
subplot(2,2,k)
plot(x,y,'r')
title(sprintf('Graph %g. Plot based upon n = %g points.' ...
, k, n10))
xlabel('x')
ylabel('y')
axis([-2,2,-.8,.8])
grid
pause(3);
end

Edited: Korosh Agha Mohammad Ghasemi on 7 Dec 2020  %https://zil.ink/korosh -------- Ways to contact me ----------
% Korosh Agha Mohammad Ghasemi !
% Chemical Engineering at Shiraz University
x=linspace(0,2,100);
figure;
for a=[0.1 0.5 1 2 4]
y=x.^a; %The function is hypothetical
if a == 0.1 %Any color can be substituted
y=x.^a;
plot(x,y,'k') %Now choose the color
hold on
elseif a == 0.5
y=x.^a;
plot(x,y,'b') %Now choose the color
hold on
elseif a==1
y=x.^a;
plot(x,y,'g') %Now choose the color
hold on
elseif a==2
y=x.^a;
plot(x,y,'r') %Now choose the color
hold on
elseif a==4
y=x.^a;
plot(x,y,'y') %Now choose the color
hold on
grid on
end
end

Da Bu on 22 Apr 2021
for a small set of colors, you can use ColorOrderIndex
t=1:0.1:2*pi;
for i=1:5
plot(t,sin(t)*i), hold on
ax = gca;
ax.ColorOrderIndex = i;
end