init_analysis_struct

 Initializes an analysis structure for pulling data out of the mysql database

 as = init_analysis_struct()

 There are two basic sub-structures within an analysis structure. 
 1) The .num structure contains numeric responses to questions. Most
    importantly this includes enums.
 2) The .txt structure contains text responses

 Both of these structures include additional fields with information for
 decoding the .data matrices.

0001 function as = init_analysis_struct()
0002 % Initializes an analysis structure for pulling data out of the mysql database
0003 %
0004 % as = init_analysis_struct()
0005 %
0006 % There are two basic sub-structures within an analysis structure.
0007 % 1) The .num structure contains numeric responses to questions. Most
0008 %    importantly this includes enums.
0009 % 2) The .txt structure contains text responses
0010 %
0011 % Both of these structures include additional fields with information for
0012 % decoding the .data matrices.
0013 
0014 % 08/19/05 Petr Janata
0015 
0016 as.name = '';  % name of the analysis
0017 as.forms = {};  % Comma-separated list of form names to aggregate into the analysis
0018 
0019 as.num.subid = {}; % Vector of subject IDs
0020 as.num.qid = [];  % Vector of question IDs
0021 as.num.qtxt = {};  % Question text
0022 as.num.vars = {};  % Output variable names
0023 as.num.data = [];  % Output data matrix (nsubs X qid) for response data
0024 as.num.datenum = [];  % Timestamps of response data
0025 as.num.niter = []; % Number of iterations of each question
0026 as.num.dfid = [];  % data format ID  - useful for enums
0027 as.num.stimidx = []; % index into master stimulus list (nsubs x nreps)
0028 
0029 as.txt.subid = {};
0030 as.txt.qid = [];
0031 as.txt.qtxt = {};
0032 as.txt.vars = {};
0033 as.txt.data = {};
0034 as.num.datenum = [];  % Timestamps of response data
0035 as.txt.niter = [];
0036 as.txt.stimidx = [];
0037 
0038 as.stims.ids = [];
0039 
0040 as.params.stims = 1;