rex_ecodes.m

function [ecode, etime] = rex_ecodes(name)

% % function [ecode, etime] = rex_ecodes(name)
% % returns all ecodes and their times for a given rex experiment
% % by James Cavanaugh 2001

ecode = [];
etime = [];

hdrsz = 512;

% short to long conversions
if ~exist('sa2la')
    s2l = inline('double(uint8(s(1)))+256*double(uint8(s(2)))','s');
    sa2la = inline('double(uint8(s(:,1)))+256.*double(uint8(s(:,2)))','s');
    
    assignin('base','s2l',s2l);
    assignin('base','sa2la',sa2la);
end;

name = char(deblank(name));

% set up the file names
fname = [rawdatadir,name];
ename = [fname,'E'];


% open the event and analog files
byteorder = 'ieee-le';  % good for mac and pc - tweak for other platforms
efp = fopen(ename, 'r', byteorder);
if efp == -1
	errordlg(['Raw data not found for ',fname],...
		'Raw Data File Not Found');
	return;
end;

% find distance from 512 to end
% here's the end
fseek(efp, 0, 'eof');
endpt = ftell(efp);
% here's the distance
numdat = (endpt - hdrsz)/2;  % /2 since we're going to read shorts

% back to just after the header
fseek(efp, hdrsz, 'bof');
toread = numdat;

% read the data in one big chunk - faster
[alldat, nread] = fread(efp, toread, 'short');
numrec = numdat/4;  % rows are 4 bytes wide - hence /4


% shape the stream into a numrec x 4 array
edat = reshape(alldat(1:(4*numrec)), 4, numrec)';

% columns 3 and 4 are parts of a long
% first: convert these shorts into ushorts
negshort = find(edat(:,3) < 0);
edat(negshort,3) = (2^16)+edat(negshort,3);
% second: convert each pair into a long
offset = (2^16).*edat(:,4) + edat(:,3);

% pull out the values
e_time = offset;
e_code = edat(:,2);

fclose(efp);

if nargout
   ecode = e_code;
   etime = e_time;
end;