The first code used to fetch the epa ozone data

%This program loads a series of file of ozone data
clear all; close all; clc;
TXSites=textread('TXSites.txt','%s');
NJSites=textread('NJSites.txt','%s');
LASites=textread('LASites.txt','%s');
year='2006';
NofF='161'; %number of total files
US='_'; %underscore
LQ='('; %lefrquote
RQ=')'; %rightquote
SF='.txt'; %surfix
n=textread('number.txt','%s'); %read 001, 002,003 ...
FN=strcat(year,US,n,LQ,NofF,RQ,SF);%generate FileName
State=[];County=[];Site=[];Date=[];Time=[];Level=[]; %define arrays
TXData=[];NJData=[];LAData=[];%define arrays
for i=1: 161;
FID=fopen(char(FN(i)));
A=textscan(FID,'%*s %*s %s %s %s %*s %*s %*s %*s %*s %n %s %n %*s %*s %*s %*s %*s %*s %*s %*s %*s %*s... %*s %*s %*s %*s','delimiter','|');
State=A{1,1};
County=A{1,2};
Site=A{1,3};
Date=A{1,4};
Time=A{1,5};
Level=A{1,6};
[r c]=size(State);
 for j=1:r
    ID=strcat(State(j),County(j),Site(j));
   if ismember(ID, TXSites)
       TXData=[TXData; [State(j), County(j), Site(j), Date(j), Time(j), Level(j)]];
   else if ismember(ID, NJSites)
           NJData=[NJData; [State(j), County(j), Site(j), Date(j), Time(j), Level(j)]];
       else if ismember(ID, LASites)
               LAData=[LAData; [State(j), County(j), Site(j), Date(j), Time(j), Level(j)]];
           end
       end
   end
 end
end
beep;