I am getting Undefined function or variable 'A', error in Untitled line 95

fileid                 =   fopen('RINEX.txt');
while ~feof(fileid)
y               =   fgetl(fileid);
a               =   strfind(y,'END OF HEADER');
if a>0
break;
end
end
% -------------------------------------------------------------------------
% -------------------------------------------------------------------------
% Reading the Data Section
% -------------------------------------------------------------------------
% -------------------------------------------------------------------------
f1                  =   (1575.42*1e6);
f2                  =   (1227.60*1e6);
m                   =   0;
r                   =   0;
while ~feof(fileid)
try
y               =   fgetl(fileid);
disp(y);
if size(y,2)<35
disp('continuing')
continue
end 
y1              =   y(1,01:30);
numsat      =   str2num(y(:,31:32));                                % Read the numbers of satellite
% ------------------------------------------------   
timehr          =   str2num(y1(:,11:12));                           % Read the hour
timemin         =   str2num(y1(:,14:15));                         % Read the minute
timesec         =   str2num(y1(:,17:26));                          % Read the second          
if timemin==0
            clc
            disp('Processing data for the hour');
            disp(timehr);
            disp(timemin);
            disp(timesec);
 end  
        % --------------------------------------------------   
        y2              =   y(1,33:end);
        ys              =   y2;     
        if (numsat>12 && numsat<24)
        y3          =   fgetl(fileid);
        ys          =   [ys  y3];
        end
        if (numsat>24)
        y4          =   fgetl(fileid);
        ys          =   [ys  y4];
        end
       satnum          =   [];                                            % Refresh this variable for every new read
        c  =  1;
        for tt=1:size(ys,2)
        if ( ys(tt)=='E' || ys(tt)=='G'  ||  ys(tt)=='R')  
        ST(c)       =   ys(tt);
        satnum(c)   =   str2num(ys(:,tt+1:tt+2));          % selecting the satellite numbers    
        tt          =   tt+2;
        c           =   c+1;
        end
        end     
        % --------------------------------------------------
        c                   =   0;
        for j = 1:numsat
            lin1            =   fgetl(fileid);
            lin2            =   fgetl(fileid);
            if (isempty(lin1) || isempty(lin2) || size(lin1,2)<63)
            continue;
            end
            rangeL1     =   str2num(lin1(:,35:46));                            % read the range in L1
            rangeL2     =   str2num(lin1(:,51:63));                            % read the range in L2          
            if (isempty(rangeL1) || isempty(rangeL2))
            continue;
            end
            z    =   satnum(j);                   % find the satellite number of the current satellite
 sod = timehr*3600 + timemin*60 + timesec; % get the current time in seconds of day
                                                                                                            
           rr    =   round(sod/30)+1;             % find the row number from the time
A(rr,:,z)   =   [sod,rangeL1,rangeL2];    % populate the corresponding page with the 
                                                                                     current data
            
          end
       pause(1)     
       catch   
       disp('Error Encountered. Moving to next Data');  
end
end
 Den       = ((1/f1.^2)-(1/f2.^2));
 for jj      = 1:size(A,3)
 A(:,4,jj) = (A(:,2,jj)-A(:,3,jj))/40.3/Den/1e16;
 end

[KSSV]

We cannot help unless the input file is given. The error is clear, it says the variable A is not defined and you are trying to use it.

[Dahati rafihna]

This is the input file

[Jan]

Please post the complete error message. Do no let the readers count, which the "line 95" is.

Answer 1

[Jan]

The variable A should be polulated in this line:

A(rr,:,z)   =   [sod,rangeL1,rangeL2];

If A in undefined, this line was not called. Check this by setting a break point in this line and running the code again.

Select all code (ctrl a) and indent it properly (ctrl i). Then it is much easier to find out visually, which loop is not entered. Check this also using the debugger: Set a break point before the loops and step through the code line by line.