% random data
T = [10 25 40 50 75];
alldataoxides = struct( ...
'pHs',3+9*rand(1,100), ...
'kds',80*rand(1,100), ...
'Temperature',T(randi(numel(T),1,100)));
% define your pH thresholds (i.e., bin edges)
pHs = [7.0, 9.1];
% define your colors (one for each bin -> one more color than you have thresholds)
colors = [ ...
0.4 0 1; ...
0 0.6 0.4; ...
1 0.6 0; ...
];
% put -Inf and Inf on the ends to include the lowest and highest bins
bin_edges = [-Inf, pHs, Inf];
% bin_idx is which bin each pH value is in
bin_idx = discretize(alldataoxides.pHs,bin_edges);
% color matrix -> the color of each data point
colorIDb = colors(bin_idx,:)
% scatter plot
sz = 50;
figure(7); hold on; box on;
scatter(alldataoxides.Temperature, log10(alldataoxides.kds), sz, colorIDb, 'filled')
