clear all
format long

% load the ctd file data
load 'ctd_data.mat'


% define the appropriate arrays for depth, pressure salinity 
% and temperature.  Establish the arrays size as nmax.

depth=ctd(:,1);
p=0.1*depth;
z=depth;

T=ctd(:,2);
S=ctd(:,3);
nmax=size(depth,1);
g=9.8;

dens=zeros(nmax,1);
E=zeros(nmax,1);
N=zeros(nmax,1);


for i=1:nmax
dens(i)=rho(S(i),T(i),p(i));
end


E(1)=-(1/dens(1))*(dens(2)-dens(1))/z(2);
E(nmax)=-(1/dens(nmax))*(dens(nmax)-dens(nmax-1))/(z(nmax)-z(nmax-1));
N(1)=sqrt(g*E(1));
N(nmax)=sqrt(g*E(nmax));

for k=2:nmax-1
    
end