How can I color a graph?

Hi everybody

I wrote this code:

function[]=mifuncionsedimentos()
P=0:1:3000;
  %Sólido
  if (P<1200)
ts=((889+17900)/((P+54)+20200/(P+54)^2));
  else 
ts=(831+0.06*P);
  end
  %Líquido
tl=(1262+0.09*P);
plot(ts,P)
title("Diagrama de fases")
xlabel("T(K)")
ylabel("P(MPa)")
hold on
plot (tl,P)
legend({'Fase Sólida','Fase Líquida'},'Location','southeast')

I need to color the 3 areas of the graph that are separated by the two functions (ts, tl). The left area is "solid", the middle area is "melt fraction" and the right area is "liquid". How can I do that?

Thank you so much!

[Walter Roberson]

P=0:1:3000;
  %Sólido
  if (P<1200)
ts=((889+17900)/((P+54)+20200/(P+54)^2));
  else 
ts=(831+0.06*P);
  end

needs to change to

  P=0:1:3000;
  ts = zeros(size(P));
  %Sólido
  mask = P<1200;
  ts(mask) = ((889+17900)./((P(mask)+54)+20200./(P(mask)+54).^2));
  ts(~mask) = (831+0.06*P(~mask));

[Walter Roberson]

Generally speaking, look at fill() to color areas of a graph.