How to create a colored, with three equally spaced rows of colors horizontally with a dimension of 6x5x3

yellow = [1,1,0]

orange = [0.8500,0.3250,0.0980]

pink = [1, 0.5, 0.8]

tci = cat (3,yellow,orange,pink)

image (tci)

I

I got this output but I need it to be horizontal.

[Star Strider]

The image function will not correctly render the colours defined in the posted code.

The patch function will.

It is then straightforward to convert the patch plot into an image if that is the desired result. Simply use the saveas function.

Answer 1

[Star Strider]

Try this —

yellow = [1,1,0];
orange = [0.8500,0.3250,0.0980];
pink = [1, 0.5, 0.8];
tci = cat (3,yellow,orange,pink);

x = [0 3 3 0; 0 3 3 0; 0 3 3 0];
y = [0 0 1 1; 1 1 2 2; 2 2 3 3];

figure
hp = patch(x', y', (0:2).');
colormap([yellow; orange; pink])

Change the order of the colours in the colormap call to order them differently.

.

[dunphy]

this is great ! may i know what this code commands?

m = [yellow;orange;pink];

tci = cat(3,m(:,1),m(:,2),m(:,3));

[Star Strider]

Thank you!

I do not use that in my code, however it defines a colormap that MATLAB uses to define the colours in a graphics object.

My code defines it as —

colormap([yellow; orange; pink])

with the same effect.

NOTE — This assignment (note the significant change from the original code):

yellow = [1,1,0];
orange = [0.8500,0.3250,0.0980];
pink = [1, 0.5, 0.8];
tci1 = cat (1,yellow,orange,pink) 

tci1 = 3×3

1.0000 1.0000 0 0.8500 0.3250 0.0980 1.0000 0.5000 0.8000

would do the same thing, so my code would use it as —

colormap(tci1)

with the same result.

.

Answer 2

[Kevin Holly]

If you want the image above to be horizontal:

yellow = [1,1,0];
orange = [0.8500,0.3250,0.0980];
pink = [1, 0.5, 0.8];
tci = cat(3,yellow',orange',pink');
image (tci)

What do mean when you state that you want a dimension of 6x5x3? This?

tci2 = imresize(tci,[6 5]);
image (tci2)

Are these the colors that you were expecting?

[dunphy]

The answer is already correct but I am expecting yellow, orange and pink. How do i code these colors?

[Kevin Holly]

yellow = [1,1,0];
orange = [0.8500,0.3250,0.0980];
pink = [1, 0.5, 0.8];
m = [yellow;orange;pink];
tci = cat(3,m(:,1),m(:,2),m(:,3));
image (tci)

tci2 = imresize(tci,[6 5]);
image (tci2)

tci3 = imresize(tci,[6 5],"method","nearest");
image (tci3)

[dunphy]

m = [yellow;orange;pink];

tci = cat(3,m(:,1),m(:,2),m(:,3));

what does these codes mean?

[Kevin Holly]

I created a matrix called m that contained the 3 RGB pixels you defined.

yellow = [1,1,0];
orange = [0.8500,0.3250,0.0980];
pink = [1, 0.5, 0.8];

m = [yellow;orange;pink]

m = 3×3

1.0000 1.0000 0 0.8500 0.3250 0.0980 1.0000 0.5000 0.8000

The first row was a yellow pixel defined as [1 1 0], which gives red the value of 1, green a value of 1, and blue a value of 0, i.e. [R G B].

tci = cat(3,m(:,1),m(:,2),m(:,3));

The cat function you were using accepts matrices that represent red, green, and blue when defining the dimension to be 3.

Knowing the first column in the matrix represents red, the second green, and the third blue, I inserted each column into the cat function.

cat(3,red,green,blue), where red = m(:,1)

To select specific points in a matrix, in this case called m, you can write the following

m(row,column)

m(2,3) %This selects the value on the second row and third column of matrix m

ans = 0.0980

you can also select arrays as inputs

m(2:3,2:3)

ans = 2×2

0.3250 0.0980 0.5000 0.8000

I selected the first column using a colon (:) to select all the rows and 1 to select the first column.

m(:,1)

ans = 3×1

1.0000 0.8500 1.0000

[dunphy]

Do you know how to code these colors while mixing colors of RGB?