Filling an array with color points

I am trying to create an array (matrix?)

I have J curves I am plotting and I want to create a vector of color values.

The matrix will have J rows and 3 entries per row. the First entry will be 0 the third entry will be 1. The second middle entry will be (i-1)*1./J. where i is my counter in the for loop.

```

j = 34; g = 3;

A = zeros(j,g);

for i= 1:j

A(:,i) = 0 (i-1)*1./j 1;

end

disp(A)

```

So I want something like, if j=34 , A=[0 0 1; 0 1/34 1; 0 2/34 1; ... ; 0 33/34 1;]

Thank you for your time and help.

Answer 1

[Les Beckham]

j = 34; g = 3; 
A = zeros(j,g);
A(:,3) = 1; % put ones in the third column
A(:,2) = ([0:j-1]/j).'; % fill in the second column (' makes it a column)
format rat
disp(A)

       0              0              1       
       0              1/34           1       
       0              1/17           1       
       0              3/34           1       
       0              2/17           1       
       0              5/34           1       
       0              3/17           1       
       0              7/34           1       
       0              4/17           1       
       0              9/34           1       
       0              5/17           1       
       0             11/34           1       
       0              6/17           1       
       0             13/34           1       
       0              7/17           1       
       0             15/34           1       
       0              8/17           1       
       0              1/2            1       
       0              9/17           1       
       0             19/34           1       
       0             10/17           1       
       0             21/34           1       
       0             11/17           1       
       0             23/34           1       
       0             12/17           1       
       0             25/34           1       
       0             13/17           1       
       0             27/34           1       
       0             14/17           1       
       0             29/34           1       
       0             15/17           1       
       0             31/34           1       
       0             16/17           1       
       0             33/34           1       

[Ursula Trigos-Raczkowski]

Thank you!

[Les Beckham]

You are quite welcome.

Answer 2

[Voss]

I think this is what you were going for:

j = 34; g = 3; 
A = zeros(j,g);
for i= 1:j
    A(i,:) = [0 (i-1)/j 1]; 
end
disp(A)

         0         0    1.0000
         0    0.0294    1.0000
         0    0.0588    1.0000
         0    0.0882    1.0000
         0    0.1176    1.0000
         0    0.1471    1.0000
         0    0.1765    1.0000
         0    0.2059    1.0000
         0    0.2353    1.0000
         0    0.2647    1.0000
         0    0.2941    1.0000
         0    0.3235    1.0000
         0    0.3529    1.0000
         0    0.3824    1.0000
         0    0.4118    1.0000
         0    0.4412    1.0000
         0    0.4706    1.0000
         0    0.5000    1.0000
         0    0.5294    1.0000
         0    0.5588    1.0000
         0    0.5882    1.0000
         0    0.6176    1.0000
         0    0.6471    1.0000
         0    0.6765    1.0000
         0    0.7059    1.0000
         0    0.7353    1.0000
         0    0.7647    1.0000
         0    0.7941    1.0000
         0    0.8235    1.0000
         0    0.8529    1.0000
         0    0.8824    1.0000
         0    0.9118    1.0000
         0    0.9412    1.0000
         0    0.9706    1.0000

And you can do it without the loop like this:

A = [zeros(j,1) (0:j-1).'/j ones(j,1)];
disp(A)

         0         0    1.0000
         0    0.0294    1.0000
         0    0.0588    1.0000
         0    0.0882    1.0000
         0    0.1176    1.0000
         0    0.1471    1.0000
         0    0.1765    1.0000
         0    0.2059    1.0000
         0    0.2353    1.0000
         0    0.2647    1.0000
         0    0.2941    1.0000
         0    0.3235    1.0000
         0    0.3529    1.0000
         0    0.3824    1.0000
         0    0.4118    1.0000
         0    0.4412    1.0000
         0    0.4706    1.0000
         0    0.5000    1.0000
         0    0.5294    1.0000
         0    0.5588    1.0000
         0    0.5882    1.0000
         0    0.6176    1.0000
         0    0.6471    1.0000
         0    0.6765    1.0000
         0    0.7059    1.0000
         0    0.7353    1.0000
         0    0.7647    1.0000
         0    0.7941    1.0000
         0    0.8235    1.0000
         0    0.8529    1.0000
         0    0.8824    1.0000
         0    0.9118    1.0000
         0    0.9412    1.0000
         0    0.9706    1.0000

[Ursula Trigos-Raczkowski]

Thank you!

[Voss]

You're welcome!