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Version: Python

TableReplayer

TableReplayer is used to replay historical data with timestamps in a new, in-memory table.

Syntax

TableReplayer(start_time: Union[Instant, str], end_time: Union[Instant, str]) -> Replayer

Parameters

ParameterTypeDescription
start_timeUnion[Instant, str]

Historical data start time.

end_timeUnion[Instant, str]

Historical data end time.

Returns

A Replayer object that can be used to replay historical data.

Methods

TableReplayer supports the following methods:

  • add_table() - Registers a table for replaying and returns the associated replay table.
  • start() - Starts replaying data.
  • shutdown() - Shuts the replayer down.

Example

The following example creates some fake historical data with timestamps and then replays it.

from deephaven import new_table
from deephaven.column import datetime_col, int_col
from deephaven.replay import TableReplayer
from deephaven.time import to_j_instant

result = new_table([
datetime_col("DateTime", [to_j_instant("2000-01-01T00:00:01 ET"), to_j_instant("2000-01-01T00:00:03 ET"), to_j_instant("2000-01-01T00:00:06 ET")]),
int_col("Number", [1, 3, 6])
])

start_time = to_j_instant("2000-01-01T00:00:00 ET")
end_time = to_j_instant("2000-01-01T00:00:07 ET")

result_replayer = TableReplayer(start_time, end_time)

replayed_result = result_replayer.add_table(result, "DateTime")

result_replayer.start()

The following example replays two tables with the same replayer.

from deephaven.replay import TableReplayer
from deephaven import empty_table

source_1 = empty_table(20).update(["Timestamp = '2024-01-01T08:00:00 ET' + i * SECOND"])
source_2 = empty_table(25).update(["Timestamp = '2024-01-01T08:00:00 ET' + i * (long)(0.8 * SECOND)"])

replayer = TableReplayer(
start_time="2024-01-01T08:00:00 ET",
end_time="2024-01-01T08:00:20 ET"
)

replayed_source_1 = replayer.add_table(table=source_1, col="Timestamp")
replayed_source_2 = replayer.add_table(table=source_2, col="Timestamp")
replayer.start()