Change plot color for increasing or decreasing x values
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Hi all...I'm pretty inexperienced with MATLAB so bear with me. I am trying to import a data set from a .txt file which has many cycles along the x-axis. Since the x-axis is temperature, I would like the increasing segment of each cycle curve (heating) to be red and the decreasing segment (cooling) to be blue. I'm not experienced enough to write a FOR loop to implement this, and I was unable to find a solution on the forums. Any help is much appreciated. Thanks!
Joseph Cheng on 12 Aug 2014
from what you described you don't really need a for loop to implement it. here is a solution to get away from a for loop
%my attempt to make something i think you're plotting.
%something like a Hysteresis curve.
y = [0 8 12 8 0 -8 -12 -8 0];
x = [2 10 10 8 -2 -10 -10 -8 2];
%find which segments are heating and cooling or staying the same.
dx = diff(x); %takes x(n+1)-x(n)
heating = dx>0; %positive dx
steady = dx ==0; %0 dx (temp values didn't change)
cooling = dx<0; %negative dx.
plotSegmentX = [x(1:end-1);x(2:end)]; %pair the segments up.
plotSegmentY = [y(1:end-1);y(2:end)]; %pair the segments up.
%plot only the heating segments and color them red. then plot only the cooling etc.
xlim([-14 14]);ylim([-12 12])