# Colored Hexagons using Patch

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stefano stefano on 6 May 2016
Commented: Image Analyst on 31 Dec 2020
Hi to everyone, I was trying to make a honeycomb with Matlab, I've had no problem with the structure but I've some trouble trying to colour those hexagons with some defined color (e.g. red, blue and violet). This is the way I get the hexagons:
theta=0:60:360;
x=sind(theta);
y=cosd(theta);
v=x(2);
for i=1:4; x=x+v*2; a(i,:)=x; b(i,:)=y; %Create the row
end
c=a'; d=b';
for j=1:4; e=d+1.5*j; re=rem(j,2); %Create the columns
if re==0, g=c;
else g=c-v;
end
colour=linspace(0,1,i)
patch(g,e,colour)
end
hold on
patch(c,d,colour)
But the colour is not specified by me, but is randomly chosen from 0 to 1.
I've read the help but I don't get the point.
Thanks in advance to everyone!!

Image Analyst on 6 May 2016
Replace this:
colour=linspace(0,1,i)
patch(g,e,colour)
with this
% Define color with whatever values you need for the color you want.
colour=[1, 0.4, 0.5]; % Any 3 values between 0 and 1, or predefined colors 'r', 'b', 'y', etc.
patch(g,e,colour);
stefano stefano on 7 May 2016
I see your answer just now: I was inspired by your post on the blog and I want to try a 2-d version!
theta=0:pi/3:2*pi;
x=sin(theta);
y=cos(theta);
v=x(2);
u=y(1)+y(2);
for i=1:columns;
x=x+v*2;
a(i,:)=x; b(i,:)=y;
c=a'; d=b';
r1=rem(i,2);
if r1==0, col1(i)='r';
else col1(i)='c';
end
axis equal
patch(c(:,i),d(:,i),col1(i));
for k=1:rows/2;
g=d+3*k;
patch(c(:,i),g(:,i),col1(i))
end
end
for j=1:columns;
e=c-v; f=d+u;
r2=rem(j,2);
if r2==0, col2(j)='y';
else col2(j)='m';
end
patch(e(:,j),f(:,j),col2(j))
for h=1:rows/2;
l=f+3*h;
patch(e(:,j),l(:,j),col2(j))
end
end
I'm now able to realize the image but I'm not able to find the proper colours as yours, can you please give me a hint?
Thanks

stefano stefano on 7 May 2016
Finally I came to the solution by creating my own color map; The result is this:
Thanks to everyone!
##### 2 CommentsShowHide 1 older comment
Image Analyst on 31 Dec 2020
Looks like the same as his comment
just with a different set of colors.