protected int findVariableIndex(DapVariable var)
    {
        for(int i = 0; i < variables.size(); i++) {
            if(variables.get(i) == var)
                return i;
        }
        return -1;
    }
protected int findVariableIndex(DapVariable var)
    {
        for(int i = 0; i < variables.size(); i++) {
            if(variables.get(i) == var)
                return i;
        }
        return -1;
    }
protected int findVariableIndex ( DapVariable var ) { for ( int i = 0 ; i < variables . size ( ) ; i ++ ) { if ( variables . get ( i ) == var ) return i ; } return - 1 ; }
/* Search the set of variables
/ * Search the set of variables