Class S3GroupedItems

Constructor

Parameters:

• items - ordered iterable of items (e.g. list, tuple, iterator, Rows), grouping tries to maintain the original item order
• groupby - attribute key or ordered iterable of attribute keys (e.g. list, tuple, iterator) for the items to be grouped by; grouping happens in order of appearance of the keys
• aggregate - aggregates to compute, list of tuples (method, key)
• value - the grouping values for this group (internal)

Overrides: object.__init__

Generator for iteration over subgroups

Decorators:

• @property

Getter for the grouping values dict

Parameters:

• key - the grouping key

Add a new item, either to this group or to a subgroup

Parameters:

• item - the item

Add an item to a subgroup. Create that subgroup if it does not yet exist.

Parameters:

• key - the grouping key
• value - the grouping value for the subgroup
• item - the item to add to the subgroup

Get a list of attribute values for the items in this group

Parameters:

• key - the attribute key

Returns:

the list of values

Aggregate item attribute values (recursively over subgroups)

Parameters:

• method - the aggregation method
• key - the attribute key

Returns:

an S3GroupAggregate instance

Represent this group and all its subgroups as string

Overrides: object.__repr__

Serialize this group as JSON

@param fields: the columns to include for each item
@param labels: columns labels as dict {key: label},
               including the labels for grouping axes
@param represent: dict of representation methods for grouping
                  axis values {colname: function}
@param as_dict: return output as dict rather than JSON string
@param master: this is the top-level group (internal)

JSON Format:

{"c": [key, ...],          ....... list of keys for visible columns
 "g": [key, ...],          ....... list of keys for grouping axes
 "l": [(key, label), ...], ....... list of key-label pairs
 "k": key,                 ....... grouping key for subgroups
 "d": [                    ....... list of sub-groups
     {"v": string,         ....... the grouping value for this subgroup (represented)
      "k": key             ....... the grouping key for subgroups
      "d": [...]           ....... list of subgroups (nested)
      "i": [               ....... list of items in this group
           {key: value,    ....... key-value pairs for visible columns
           }, ...
      ],
      "t": {               ....... list of group totals
          key: value,      ....... key-value pairs for totals
      }
     }, ...
    ],
"i": [...],                ....... list of items (if no grouping)
"t": [...],                ....... list of grand totals
"e": boolean               ....... empty-flag
}