You may try the following:
clear; clc;
coord = [1 1;4 4;7 7;10 10];
a = 0.5;
b = 1.5;
r = (b-a).*rand(4, 1) + a;
nLevel = 100; % Number of level in the colormap
cmap = colormap(jet(nLevel)); % Select your colormap
polyFaceColor = cmap(ceil((r-a)*nLevel),:); % Calculate which level of the colormap for each polygon
for i = 1:length(coord)
pgon(i) = nsidedpoly(6, 'Center', coord(i, :), 'SideLength', 2);
end
pg = plot(pgon);
axis off
axis equal
for i = 1:length(coord)
pg(i).FaceColor = polyFaceColor(i,:); % Assign the colormap to the polygon
end
str = num2str(r, 2);
t2 = text(coord(:, 1), coord(:, 2), str, ...
'HorizontalAlignment', 'center','VerticalAlignment','middle', 'FontSize', 10, 'FontName', 'Times');
