MATLAB: Legend in plot using forloop

legend

Hello,

I am trying to plot the legend of 3 things here: temperature data (continuous blue line), the starting point of a sit period (green asterix), end point of a sit period (red asterix). The forloop runs over 2 specified values (4 and 34).

[row2,col2] = find(start_sit_periods);
for i = col2;
t = linspace(0,(((length(temp_i1)/fs)/60)/60),length(temp_i1)); 
figure(1)
ee = linspace(0,((length(x_i1)/fs)/60),length(x_i1));
subplot 411
plot(ee,temp_i1)
xlabel('Time (minutes)')
ylabel('Temperature (°C)')
hold on
plot(ee(start_sit_periods(1,i)),temp_i1(start_sit_periods(1,i)),'*g')
plot(ee(end_sit_periods(1,i)),temp_i1(end_sit_periods(1,i)),'*r')
legend('Leg temperature','Start sit','End sit')
subplot 412
plot(ee,abs(x_i1))
xlabel('Time (minutes)')
ylabel('Acceleration (m/s²)')
subplot 413
plot(ee,abs(y_i1))
xlabel('Time (minutes)')
ylabel('Acceleration (m/s²)')
subplot 414
plot(ee,abs(z_i1))
xlabel('Time (minutes)')
ylabel('Acceleration (m/s²)')
end

I've tried some

things, but the legend stays wrongs.

Can anyone help?

Thanks!

Best Answer

Not quite sure what you meant by "the legend stays wrong", but please try this if my guess is correct.

figure(1)
ee = linspace(0,((length(x_i1)/fs)/60),length(x_i1));
subplot 411
p1 = plot(ee,temp_i1)
xlabel('Time (minutes)')
ylabel('Temperature (°C)')
hold on
p2 = plot(ee(start_sit_periods(1,i)),temp_i1(start_sit_periods(1,i)),'*g')
p3 = plot(ee(end_sit_periods(1,i)),temp_i1(end_sit_periods(1,i)),'*r')
legend([p1 p2 p3], {'Leg temperature','Start sit','End sit'})

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MATLAB: About FFT of sin(x) / x , how to plot

Hi, I was able to get a plot by removing the discontinuity in the signal. Is this what you were expecting?

% show the " y=sin(t) / t " in FFT spectrum
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MATLAB: How to assign plotting properties to a subplot within a loop

Hi,

You have done well in all steps except for one small point after else condition:

 for k = 1:3
    figure(1)
    subplot(3,1,k)
    plot(T{k},F{k})
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    xlabel('Time (s)')
    ylabel('Acceleration (g)')
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