Argument of a signal

I've energy-time signal data e(t)having discrete values(file attached). I want to do the following operation:

• t[5%]=arg(e(t)) at 5% peak value.
• Plot(t,e(t-t[5%])).

How to write code for this?

[Walter Roberson]

When you write arg(e(t)) at 5% peak value, do you mean that you want to know the index of the point at which the energy reaches 5% of its peak?

Answer 1

[Walter Roberson]

 data = xlsread('data.xls');
 e = data(:,2);
 t = data(:,3);
 maxe = max(e);
 e5 = maxe * 0.05;
 [~, idx5] = min( abs(e - e5) );
 t5 = t(idx5);

 plot(t(1:end-idx5+1), e(idx5:end))

... I guess. Your notation for what you want to plot is not clear.