MATLAB script is yielding scaled outputs

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I found this script which reads in .rpc/.rsp files (format - binary, data type - short integer, file type - time history) and writes data values to column vectors. Script origin can be found here: https://www.mathworks.com/matlabcentral/fileexchange/9357-load-rpc-files-of-type-binary-short_integer-time_history

function [TIME,DATA,FFORMAT]=load2_rpc(varargin)
if length(varargin)==0; % filename missing
    %[fname, pname] = uigetfile('*.rpc','Choose rpc III file');
    [fname, pname, filterindex] = uigetfile( ...
        {'*.rpc;*.rsp', '(*.rpc *.rsp) files';
        '*.rpc',  '*.rpc - RPC file'; ...
        '*.rsp','*.rsp - RPC response file'; ...
        '*.*',  'All Files (*.*)'}, ...
        'Choose RPC / III file');
    FFORMAT.NAME=fname;
    if fname==0;
        return
    end
    fname=[pname fname];
elseif length(varargin)==1;
    fname = varargin{1};
else
    disp('Warning, wrong number of parameters')
end
% initialize standard rpc fullscale, if not defined in rpc header
FFORMAT.num_fullscale=32752;
% intitialize standard integer fullscale
int_FS=32768;
fid = fopen(fname);     % open rpc-file for reading
if fid<=0
    disp('file could not be opened')
    return
end
fdir = dir(fname);
FFORMAT.fsize = fdir.bytes;
% read Header
FFORMAT.num_para=8; %minimum 8x 128byte header lines
% (NUM_PARAMS must be found within these 1024 bytes)
FFORMAT.num_header_blocks=2;
para_found=0;
lin=0;
while lin<FFORMAT.num_header_blocks*4 | mod(lin,4)~=0;
    tline = fread(fid, 128, 'uint8=>char');
    lin=lin+1;
    %disp(num2str(lin))
    %convert to true string
    for n=1:128
        if double(tline(n))==0
            tline(n)=' ';
        end
    end
    oline=tline';
    tline=upper(tline)'; %create upper case row-String
    %disp(tline)
    para='INT_FULL_SCALE';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.num_fullscale=str2num(strtrim(oline(33:33+80)));
    end
    para='NUM_HEADER_BLOCKS';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.num_header_blocks=str2num(strtrim(oline(33:33+80)));
    end
    para='NUM_PARAMS';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.num_para=str2num(strtrim(oline(33:33+80)));
        para_found=1;
    end
    para='FORMAT';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.format=strtrim(oline(33:33+80));
        if upper(FFORMAT.format) ~= 'BINARY'
            disp('WARNING: rpc file format not binary, may cause errors');
        end
    end
    para='DATA_TYPE';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.data_type=strtrim(oline(33:33+80));
        if upper(FFORMAT.data_type) ~= 'SHORT_INTEGER'
            disp('WARNING: rpc data not of type "short_integer", may cause errors');
        end
    end
    para='DELTA_T';
    if  strcmp(para,tline(1:length(para)))
        FFORMAT.dt=str2num(strtrim(oline(33:33+15)));
        FFORMAT.fsample=1/str2num(strtrim(oline(33:33+80)));
    end
    para='CHANNELS';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.num_chan=str2num(strtrim(oline(33:33+80)));
    end
    para='PTS_PER_FRAME';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.num_PPF=str2num(strtrim(oline(33:33+80)));
    end
    para='PTS_PER_GROUP';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.num_PPG=str2num(strtrim(oline(33:33+80)));
    end
    para='FRAMES';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.num_frames=str2num(strtrim(oline(33:33+80)));
    end
    para='DATE';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.dat_date=strtrim(oline(33:33+80));
    end
    para='FILE_TYPE';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.file_type=strtrim(oline(33:33+80));
    end
    para='TIME_TYPE';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.time_type=strtrim(oline(33:33+80));
    end
    para='OPERATION';
    if  strcmp(para,tline(1:length(para)));
        FFORMAT.operation=strtrim(oline(33:33+80));
    end
    para='SCALE.CHAN_';
    if  strcmp(para,tline(1:length(para)));
        tmp_ch=str2num(strtrim(oline(length(para)+1:length(para)+4)));
        FFORMAT.chan(tmp_ch).scale = str2num(strtrim(oline(33:33+80)));
    end
    para='LOWER.LIMIT.CHAN_';
    if  strcmp(para,tline(1:length(para)));
        tmp_ch=str2num(strtrim(oline(length(para)+1:length(para)+4)));
        FFORMAT.chan(tmp_ch).lolim = str2num(strtrim(oline(33:33+80)));
    end
    para='UPPER.LIMIT.CHAN_';
    if  strcmp(para,tline(1:length(para)));
        tmp_ch=str2num(strtrim(oline(length(para)+1:length(para)+4)));
        FFORMAT.chan(tmp_ch).uplim = str2num(strtrim(oline(33:33+80)));
    end
    para='MAP.CHAN_';
    if  strcmp(para,tline(1:length(para)));
        tmp_ch=str2num(strtrim(oline(length(para)+1:length(para)+4)));
        FFORMAT.chan(tmp_ch).map = strtrim(oline(33:33+80));
    end
    para='DESC.CHAN_';
    if  strcmp(para,tline(1:length(para)));
        tmp_ch=str2num(strtrim(oline(length(para)+1:length(para)+4)));
        FFORMAT.chan(tmp_ch).desc = strtrim(oline(33:33+80));
    end
    para='UNITS.CHAN_';
    if  strcmp(para,tline(1:length(para)));
        tmp_ch=str2num(strtrim(oline(length(para)+1:length(para)+4)));
        FFORMAT.chan(tmp_ch).units = strtrim(oline(33:33+80));
    end
end
%disp(chan(:))
anaName = find(fname=='\');
FFORMAT.NAME = fname; %(anaName(length(anaName)):length(fname));
if length(anaName) > 0
    FFORMAT.NAME = fname(1+anaName(end):end);
end
if para_found==0
    disp('Parameter NUM_PARAMS missing within the first 1024 bytes');
    return
end
data_read=lin*128;
% initialize matrix DATA size
FFORMAT.data_length=round((FFORMAT.fsize-data_read)/(2*FFORMAT.num_chan));
DATA(1:FFORMAT.data_length,1:FFORMAT.num_chan)=0;
% read data
f=0;
fstep=round(FFORMAT.num_PPG / FFORMAT.num_PPF);
ink=0;
data_read=0;
h=waitbar(0,['Reading file ' FFORMAT.NAME]);
next_wb=0.2;
data_step=round(0.2*FFORMAT.data_length);
while ~feof(fid) & f < FFORMAT.num_frames
    for fi = 1:FFORMAT.num_chan
        tline = fread(fid, FFORMAT.num_PPG, 'int16');
        %if length(tline) < FFORMAT.num_PPG
        %    tline(length(tline):FFORMAT.num_PPG)=0;
        %end
        DATA(ink*FFORMAT.num_PPG+1:(ink+1)*FFORMAT.num_PPG,fi)=tline;
    end
    data_read=data_read + FFORMAT.num_PPG;
    if data_read > data_step
        waitbar(next_wb);
        next_wb=next_wb+0.2;
        data_step=data_step + round(0.2 * FFORMAT.data_length);
    end
    f=f + fstep;
    ink=ink+1;
end
close(h);
fclose(fid);
%DATA=DATA';
ndata = length(DATA(:,1));
%TIME = linspace(0, ndata / FFORMAT.fsample, 20)';
assignin('base','data',DATA);
FFORMAT

Output of FFORMAT

When reading .rsp files through this script, the y-axis outputs are coming out but being multiplied by some seemingly random multiplier, which differs for each channel. I don't see where in the script is the output being multiplied by value, however. Does anyone know why this is happening?