getGenesFromGrRules

getGenesFromGrRules  Extract gene list and rxnGeneMat from grRules array.

 USAGE:

   [genes,rxnGeneMat] = getGenesFromGrRules(grRules, originalGenes);

 INPUTS:

   grRules     A cell array of model grRules, from which a list of genes
               are to be extracted.
               NOTE: Boolean operators can be text ("and", "or") or
                     symbolic ("&", "|"), but there must be a space
                     between operators and gene names/IDs.
   originalGenes     The original gene list from the model as reference

 OUTPUTS:

   genes       A unique list of all gene IDs that appear in grRules.

   rxnGeneMat  (Optional) A binary matrix indicating which genes
               participate in each reaction, where rows correspond to
               reactions (entries in grRules) and columns correspond to
               genes.

0001 function [genes,rxnGeneMat] = getGenesFromGrRules(grRules, originalGenes)
0002 %getGenesFromGrRules  Extract gene list and rxnGeneMat from grRules array.
0003 %
0004 % USAGE:
0005 %
0006 %   [genes,rxnGeneMat] = getGenesFromGrRules(grRules, originalGenes);
0007 %
0008 % INPUTS:
0009 %
0010 %   grRules     A cell array of model grRules, from which a list of genes
0011 %               are to be extracted.
0012 %               NOTE: Boolean operators can be text ("and", "or") or
0013 %                     symbolic ("&", "|"), but there must be a space
0014 %                     between operators and gene names/IDs.
0015 %   originalGenes     The original gene list from the model as reference
0016 %
0017 % OUTPUTS:
0018 %
0019 %   genes       A unique list of all gene IDs that appear in grRules.
0020 %
0021 %   rxnGeneMat  (Optional) A binary matrix indicating which genes
0022 %               participate in each reaction, where rows correspond to
0023 %               reactions (entries in grRules) and columns correspond to
0024 %               genes.
0025 %
0026 
0027 
0028 % handle input arguments
0029 if nargin < 2
0030     originalGenes = [];
0031 end
0032 
0033 % check if the grRules use written or symbolic boolean operators
0034 if any(contains(grRules,{' & ',' | '}))
0035     % fix some potential missing spaces between parentheses and &/|
0036     grRules = regexprep(grRules,'\)&',') &');   % ")&"  ->  ") &"
0037     grRules = regexprep(grRules,'&\(','& (');   % "&("  ->  "& ("
0038     grRules = regexprep(grRules,'\)\|',') |');  % ")|"  ->  ") |"
0039     grRules = regexprep(grRules,'\|\(','| (');  % "|("  ->  "| ("
0040 else
0041     % fix some potential missing spaces between parentheses and AND/OR
0042     grRules = regexprep(grRules,'\)and',') and');  % ")and" ->  ") and"
0043     grRules = regexprep(grRules,'and\(','and (');  % "and(" ->  "and ("
0044     grRules = regexprep(grRules,'\)or',') or');    % ")or"  ->  ") or"
0045     grRules = regexprep(grRules,'or\(','or (');    % "or("  ->  "or ("
0046     
0047     % convert "and" to "&" and "or" to "|" (easier to work with symbols)
0048     grRules = regexprep(grRules, ' or ', ' | ');
0049     grRules = regexprep(grRules, ' and ', ' & ');
0050 end
0051 
0052 % extract list of genes from each reaction
0053 rxnGenes = cellfun(@(r) regexprep(unique(strsplit(r,{' | ',' & '})),'[\(\) ]+',''),grRules,'UniformOutput',false);
0054 
0055 % construct new gene list
0056 nonEmpty = ~cellfun(@isempty,rxnGenes);
0057 genes = unique([rxnGenes{nonEmpty}]');
0058 genes(cellfun(@isempty,genes)) = [];
0059 
0060 if ~isempty(originalGenes)
0061     if ~isequal(sort(originalGenes), sort(genes))
0062         error('The grRules and original gene list are inconsistent!');
0063     else
0064         genes = originalGenes;
0065     end
0066 end
0067 
0068 % construct new rxnGeneMat (if requested)
0069 if nargout > 1
0070     rxnGeneCell = cellfun(@(rg) ismember(genes,rg),rxnGenes,'UniformOutput',false);
0071     rxnGeneMat = sparse(double(horzcat(rxnGeneCell{:})'));
0072 end