Change color of 2D plot line depending on 3rd value

Question

I have a data set that looks like this

 140400 70.7850 1
 140401 70.7923 2
 140402 70.7993 3
 140403 70.8067 4
 140404 70.8139 5
 140405 70.8212 3
         


        

Answer 1

My desired effect was achieved below (simplified):

        indices(1).index  = find( data( 1 : end - 1, 3) == 1);
        indices(1).color  = [1 0 0]; 
        indices(2).index  = find( data( 1 : end - 1, 3) == 2 | ...
                                  data( 1 : end - 1, 3) == 3);
        indices(2).color  = [1 1 0];
        indices(3).index  = find( data( 1 : end - 1, 3) == 4 | ...
                                  data( 1 : end - 1, 3) == 5);
        indices(3).color  = [0 1 0];
        indices(4).index  = find( data( 1 : end - 1, 3) == 10);
        indices(4).color  = [0 0 0];
        indices(5).index  = find( data( 1 : end - 1, 3) == 15);
        indices(5).color  = [0 0 1];

    % Loop through the locations of the values and plot their data points
    % together (This will save time vs. plotting each line segment
    % individually.)

    for iii = 1 : size(indices,2)

        % Store locations of the value we are looking to plot
        curindex = indices(iii).index;

        % Get color that corresponds to that value
        color = indices(iii).color;

            % Create X and Y that will go into plot, This will make the line
            % segment from P1 to P2 have the color that corresponds with P1
            x = [data(curindex, 1), data(curindex + 1, 1)]';
            y = [data(curindex, 2), data(curindex + 1, 2)]';

            % Plot the line segments
            hold on
            plot(x,y,'Color',color,'LineWidth',lineWidth1)            

    end