barstate

The barstate namespace provides boolean flags indicating the current bar’s position in the historical data and real-time status. Use these to identify first/last bars, detect new bars, or check whether the script is running on confirmed, historical, or real-time data.

Quick Example 

from pynecore.lib import (
    close, high, label, bar_index, barstate, script
)

@script.indicator(title="Bar State Detector", overlay=True)
def main():
    # Mark the first and last bars
    if barstate.isfirst:
        label.new(bar_index, high, "First")
    
    if barstate.islast:
        label.new(bar_index, high, "Last")
    
    # Log bar state information
    if barstate.isconfirmed:
        # This is the final update for the current bar
        pass
    
    if barstate.ishistory:
        # We are on a historical bar
        pass

Variables

barstate.isfirst

Returns true if the current bar is the first bar in the dataset, false otherwise.

Type: bool

if barstate.isfirst:
    label.new(bar_index, high, "Start")

barstate.islast

Returns true if the current bar is the last bar in the dataset, false otherwise. For real-time bars, this is always true.

Type: bool

if barstate.islast:
    label.new(bar_index, high, "End")

barstate.isconfirmed

Returns true if the script is calculating the final update of the current bar (at bar close). The next script execution will be on a new bar.

Type: bool

if barstate.isconfirmed:
    # Execute only once per bar, at close
    pass

barstate.ishistory

Returns true if the current bar is a historical bar (not real-time), false otherwise.

Type: bool

if barstate.ishistory:
    # Processing historical data
    pass

barstate.islastconfirmedhistory

Returns true if the script is executing on the dataset’s last bar when the market is closed, or on the bar immediately before the real-time bar when the market is open.

Type: bool

if barstate.islastconfirmedhistory:
    # Last historical bar before real-time data begins
    pass

barstate.isnew

Returns true if the script is currently calculating on a new bar, false otherwise.

Type: bool

if barstate.isnew:
    # New bar detected
    pass

barstate.isrealtime

Returns true if the current bar is a real-time bar (live market data), false otherwise.

Type: bool

if barstate.isrealtime:
    # Real-time bar processing
    pass

Compatibility Notes

Backtesting (historical data only): every bar is a closed historical bar.

  • barstate.ishistory and barstate.isconfirmed are true on every bar.
  • barstate.isnew is true on every bar: each historical bar is calculated once.
  • barstate.isrealtime is false on every bar.
  • barstate.islastconfirmedhistory is false on every bar, including the dataset’s last bar.

Live mode (pyne run --live, or pyne run --broker): the historical phase behaves like a backtest, except that barstate.islast is false on the historical bars and barstate.islastconfirmedhistory is true on the final historical bar. On the streamed bars barstate.ishistory is false, barstate.isrealtime and barstate.islast are true, barstate.isconfirmed is true only on the bar-closing update, and barstate.isnew marks the first execution of a new bar. See Live Mode for the per-tick values.