rinexe.m

it is a source code from mathworks

function rinexe(ephemerisfile, outputfile)
%RINEXE Reads a RINEX Navigation Message file and
%	     reformats the data into a matrix with 21
%	     rows and a column for each satellite.
%	     The matrix is stored in outputfile

%Typical call: rinexe('pta.96n','pta.nav')

%Kai Borre 04-18-96
%Copyright (c) by Kai Borre
%$Revision: 1.0 $  $Date: 1997/09/24  $

% Units are either seconds, meters, or radians
fide = fopen(ephemerisfile);
head_lines = 0;
while 1  % We skip header
   head_lines = head_lines+1;
   line = fgetl(fide);
   answer = findstr(line,'END OF HEADER');
   if ~isempty(answer), break;  end;
end;
head_lines
noeph = -1;
while 1
   noeph = noeph+1;
   line = fgetl(fide);
   if line == -1, break;  end
end;
noeph = noeph/8
frewind(fide);
for i = 1:head_lines, line = fgetl(fide); end;

% Set aside memory for the input
svprn    = zeros(1,noeph);
weekno   = zeros(1,noeph);
t0c      = zeros(1,noeph);
tgd      = zeros(1,noeph);
aodc     = zeros(1,noeph);
toe      = zeros(1,noeph);
af2      = zeros(1,noeph);
af1      = zeros(1,noeph);
af0      = zeros(1,noeph);
aode     = zeros(1,noeph);
deltan   = zeros(1,noeph);
M0       = zeros(1,noeph);
ecc      = zeros(1,noeph);
roota    = zeros(1,noeph);
toe      = zeros(1,noeph);
cic      = zeros(1,noeph);
crc      = zeros(1,noeph);
cis      = zeros(1,noeph);
crs      = zeros(1,noeph);
cuc      = zeros(1,noeph);
cus      = zeros(1,noeph);
Omega0   = zeros(1,noeph);
omega    = zeros(1,noeph);
i0       = zeros(1,noeph);
Omegadot = zeros(1,noeph);
idot     = zeros(1,noeph);
accuracy = zeros(1,noeph);
health   = zeros(1,noeph);
fit      = zeros(1,noeph);

for i = 1:noeph
   line = fgetl(fide);	  %
   svprn(i) = str2num(line(1:2));
   year = line(3:6);
   month = line(7:9);
   day = line(10:12);
   hour = line(13:15);
   minute = line(16:18);
   second = line(19:22);
   af0(i) = str2num(line(23:41));
   af1(i) = str2num(line(42:60));
   af2(i) = str2num(line(61:79));
   line = fgetl(fide);	  %
   IODE = line(4:22);
   crs(i) = str2num(line(23:41));
   deltan(i) = str2num(line(42:60));
   M0(i) = str2num(line(61:79));
   line = fgetl(fide);	  %
   cuc(i) = str2num(line(4:22));
   ecc(i) = str2num(line(23:41));
   cus(i) = str2num(line(42:60));
   roota(i) = str2num(line(61:79));
   line=fgetl(fide);
   toe(i) = str2num(line(4:22));
   cic(i) = str2num(line(23:41));
   Omega0(i) = str2num(line(42:60));
   cis(i) = str2num(line(61:79));
   line = fgetl(fide);	    %
   i0(i) =  str2num(line(4:22));
   crc(i) = str2num(line(23:41));
   omega(i) = str2num(line(42:60));
   Omegadot(i) = str2num(line(61:79));
   line = fgetl(fide);	    %
   idot(i) = str2num(line(4:22));
   codes = str2num(line(23:41));
   weekno = str2num(line(42:60));
   L2flag = str2num(line(61:79));
   line = fgetl(fide);	    %
   svaccur = str2num(line(4:22));
   svhealth = str2num(line(23:41));
   tgd(i) = str2num(line(42:60));
   iodc = line(61:79);
   line = fgetl(fide);	    %
   tom(i) = str2num(line(4:22));
   spare = line(23:41);
   spare = line(42:60);
   spare = line(61:79);
end
status = fclose(fide)

%  Description of variable eph.
eph(1,:)  = svprn;
eph(2,:)  = af2;
eph(3,:)  = M0;
eph(4,:)  = roota;
eph(5,:)  = deltan;
eph(6,:)  = ecc;
eph(7,:)  = omega;
eph(8,:)  = cuc;
eph(9,:)  = cus;
eph(10,:) = crc;
eph(11,:) = crs;
eph(12,:) = i0;
eph(13,:) = idot;
eph(14,:) = cic;
eph(15,:) = cis;
eph(16,:) = Omega0;
eph(17,:) = Omegadot;
eph(18,:) = toe;
eph(19,:) = af0;
eph(20,:) = af1;
eph(21,:) = toe;

fidu = fopen(outputfile,'w');
count = fwrite(fidu,[eph],'double');
fclose all
%%%%%%%%% end rinexe.m %%%%%%%%%