Trying to learn how to add a threshold trigger and peak markers.

%% Import Files

signal = 58; %chose column you're interested in in data

processedfilename = ['data1/LT1.txt'];
opts = detectImportOptions(processedfilename)
b = readtable(processedfilename,'ReadVariableNames',true); 
LANK_ANG = b(5:end,signal);
pass = table2array(LANK_ANG);

processedfilename = ['data1/LT.txt'];
opts = detectImportOptions(processedfilename)
b = readtable(processedfilename,'ReadVariableNames',true); 
LANK_ANG = b(5:end,signal);
pow = table2array(LANK_ANG);

processedfilename = ['data1/LT1.txt'];
opts = detectImportOptions(processedfilename)
b = readtable(processedfilename,'ReadVariableNames',true); 
Z__Aaron_PneumaticAnkle_ExportedData_TB30_PassiveEvaluation__56 = b(5:end,signal);
pass = table2array(Z__Aaron_PneumaticAnkle_ExportedData_TB30_PassiveEvaluation__56);
%% Plot Data
signal = 58
figure;
plot(pass(:,1))
hold on
plot(pow(:,1))

plot(601,pass(601,1),'o')
plot(5749,pass(5749,1),'o')

This is my current script. I am currently trying to learn how to add threshold trigger that marks when the red line goes over .95 on the Y axis. I also am trying to find a way to put a marker on all of the peaks of the two lines. I am brand new to matlab and any help would be great. Thanks!

[Marshall Harkrider]

Please let me know if there is any missing info I could provide that would be of assistance.

Answer 1

[Star Strider]

Try something like this —

x = linspace(0,10,500);
red_line = sin(2*pi*x)*1.5;

trigger = find(diff(sign(red_line - 0.95)));

figure
plot(x, red_line, '-r')
hold on
plot(x(trigger), 0.95*ones(size(trigger)), 'xb', 'MarkerSize',10)
hold off
grid

Make appropriate changes to work with your code and data.

.

[Marshall Harkrider]

Thank you!!

[Star Strider]

As always, my pleasure!

With respect to the peaks, use findpeaks or islocalmax. (My apologies for not including those originally.)