%  earthquake-NS.m
%
%  Script which inputs, plots and analyzes the 1940 El Centro
%  earthquake north-south acceleration data.

%  Date:  11-1-06
%  Input the data
load elcentro_NS.dat -ascii
%  Column 1 time ; Column 2 acceleration G's
data = elcentro_NS;
accel = 386.4*data(:,2);
time = data(:,1);
dt=time(2)-time(1);
%  Create the times that go with the acceleration.
%  Plot the time-accel data

plot(time,accel,'r-')
grid
title('N-S Acceleration History 1940 El Centro EarthQuake')
xlabel('time (sec) ')
ylabel('accel. (in/s^2)')
axis([0 31 -150 150])

%  Find the maximum and minimum values of the acceleration data
%  and print them.

[amax,imax] = max(accel);
[amin,imin] = min(accel);
fprintf('\nThe max accel is %5.3f in/s^2 and occurs at time = %5.3f sec.\n ',amax,time(imax))
fprintf('The min accel is %5.3f in/s^2 and occurs at time = %5.3f sec.\n',amin,time(imin))