deephaven.table_factory¶

This module provides various ways to make a Deephaven table.

class DynamicTableWriter(col_defs)[source]¶

Bases: deephaven._wrapper.JObjectWrapper

The DynamicTableWriter creates a new in-memory table and supports writing data to it.

This class implements the context manager protocol and thus can be used in with statements.

close()[source]¶

Closes the writer.

Raises: DHError –
Return type: None

j_object_type¶: alias of io.deephaven.engine.table.impl.util.DynamicTableWriter

write_row(*values)[source]¶

Writes a row to the newly created table.

The type of a value must be convertible (safely or unsafely, e.g. lose precision, overflow, etc.) to the type of the corresponding column.

Parameters: *values (Any) – the values of the new row, the data types of these values must match the column definitions of the table
Raises: DHError –
Return type: None

empty_table(size)[source]¶

Creates a table with rows but no columns.

Parameters: size (int) – the number of rows
Return type: Table
Returns: a Table
Raises: DHError –

merge(tables)[source]¶

Combines two or more tables into one aggregate table. This essentially appends the tables one on top of the other. Null tables are ignored.

Parameters: tables (List[Table]) – the source tables
Returns: a Table
Raises: DHError –

merge_sorted(tables, order_by)[source]¶

Combines two or more tables into one sorted, aggregate table. This essentially stacks the tables one on top of the other and sorts the result. Null tables are ignored. mergeSorted is more efficient than using merge followed by sort.

Parameters

tables (List[Table]) – the source tables
order_by (str) – the name of the key column

Return type

Table

Returns

a Table

Raises

DHError –

new_table(cols)[source]¶

Creates an in-memory table from a list of input columns. Each column must have an equal number of elements.

Parameters: cols (List[InputColumn]) – a list of InputColumn
Return type: Table
Returns: a Table
Raises: DHError –

time_table(period, start_time=None)[source]¶

Creates a table that adds a new row on a regular interval.