The Treemap97 .map file format:


treeid;num_of_attrs;Xattr1_name;...;XattrN_name;
[item_name;attr1_val;...;attrn_val;[subitem_name;...;][...]]

notes:  No CRLFs, ;=delim, do nesting with [].

Field meanings:
treeid = unused integer
num_of_attrs = number of attributes for each object
X = attr type:  0=integer, 1=real, 2=string, 3=date
attrn_name = The string name of the attr n