how do you plot a 2D scatter with colour defined by 3rd variable in given limits?

I am happy plotting 2d scatters but i want to colour in my 2 variables (temperature and fugacityco2) according to the day of the year (julian day). I found that if the 3rd variable is the same length as the x and y variables it will plot it over the given color range given, which has worked. BUT i want to be able to set it so that for different periods eg days 0-50 it is red 'r', 50-100,blue etc etc. help would be GREATLY appreciated thanks!

My code is below

% scatter of points figure (5);

scatter(temperature,fugacityco2_recomputed,1,julian_day);

colorbar;

axis([-2.3 -1.75 100 1000]);

xlabel('temperature');

ylabel('fugacity_co2');

Answer 1

Why don't you just pass in the colors as the 4th argument to scatter()?