How can I change the line color in a graph using stem?

Hello. I need to change the color of my graph when the value exceeds a certain limit. I use stem for the graph.

% Create figure figure1 = figure('Name','Peak Distortion','Color',[0 0 0]);

% Create axes

axes1 = axes('Parent',figure1,... 'Position',[0.130625 0.904793101727064 0.774375 0.0790343915343916],... 'Color',[0 0 0]);

% Uncomment the following line to preserve the Y-limits of the axes

ylim(axes1,[0 40]);

hold(axes1,'all');

% Create stem

stem(X1,Y1,'Marker','none','Color',[0 0.498039215803146 0],'Parent',axes1);

% Create ylabel

ylabel('Vib 1','VerticalAlignment','top','Color',[1 1 1],'Rotation',0);

when the value of Y1 is greater than 30 I want a red line in my plot any sugestion thanks

Answer 1

[Star Strider]

This works, although you’ll have to adapt it slightly to fit with your existing plot calls (insert: 'Parent',axes1):

X1 = 1:25;
Y1 = randi(50, 1, 25);

figure(1)
stem(X1,Y1,'Marker','none','Color',[0 0.498039215803146 0]);
hold on
stem(X1(Y1>30),Y1(Y1>30),'Marker','none','Color',[1 0 0]);
hold off

I assume what you want is the stem colour to change, since you’re not using markers. My code here simply overplots the data that are >30 with a red stem line in the second stem call.

[Alejandro Franco]

thanks!!

[Star Strider]

My pleasure!