Coding Narrow Range 7 (NR7) Scanner Using Python and Zerodha
To detect and print the last date each stock had a “Narrow Range 7 (NR7)” pattern within the specified date range, you can modify the code from the last chapter as follows.
from datetime import datetime, timedelta
# Define the date range
start_date = datetime.strptime('2023-08-01', '%Y-%m-%d')
end_date = datetime.strptime('2023-09-01', '%Y-%m-%d')
# Define the interval (in minutes)
interval = 'day'
# Iterate through the list of stock symbols
for symbol in symbol_list:
# Fetch instrument data for the current stock symbol
instruments = kite.ltp([symbol])
# Check if the stock symbol is in the instruments dictionary
if symbol in instruments:
instrument_token = instruments[symbol]['instrument_token']
if instrument_token:
# Fetch historical data for the stock
historical_data = kite.historical_data(instrument_token, start_date, end_date, interval='day')
# Initialize variables to track NR7 candles
nr7_candles = []
# Iterate through historical data to detect NR7 candles
for i in range(6, len(historical_data)):
current_candle = historical_data[i]
# Calculate the trading range for the previous six candles
previous_candles = historical_data[i - 6:i]
trading_ranges = [candle['high'] - candle['low'] for candle in previous_candles]
# Check if the current candle has the narrowest range among the previous six (NR7)
if min(trading_ranges) == trading_ranges[-1]:
nr7_candles.append(current_candle)
# Print or post detected NR7 candles for the entire date range
for candle in nr7_candles:
print(f"NR7 Candle detected for {symbol} on {candle['date']}")
else:
print(f"Instrument token not found for {symbol}")
else:
print(f"{symbol} not found in instruments")
The output looks like –
NR7 Candle detected for NSE:NIFTY BANK on 2023-08-18 00:00:00+05:30
NR7 Candle detected for NSE:NIFTY BANK on 2023-08-21 00:00:00+05:30
NR7 Candle detected for NSE:NIFTY BANK on 2023-08-22 00:00:00+05:30
NR7 Candle detected for NSE:NIFTY BANK on 2023-08-23 00:00:00+05:30
...
...
...
...
NR7 Candle detected for NSE:TATACONSUM on 2023-08-17 00:00:00+05:30
NR7 Candle detected for NSE:NIFTY FIN SERVICE on 2023-08-18 00:00:00+05:30
NR7 Candle detected for NSE:NIFTY FIN SERVICE on 2023-08-21 00:00:00+05:30
NR7 Candle detected for NSE:NIFTY FIN SERVICE on 2023-08-30 00:00:00+05:30
Here’s an explanation of the modifications made from the NR4 Scanner to the NR7 Scanner:
- Change in Date Range and Interval:
- In the NR4 Scanner, the date range is defined as ‘2023-08-01’ to ‘2023-09-01’, while in the NR7 Scanner, the date range is the same.
- The interval remains ‘day’ in both cases, indicating that daily candlestick data is used for analysis.
- Variable and Candle Range Adjustment:
- In the NR4 Scanner, the loop iterates through historical data with a range of 3 to len(historical_data) to calculate the trading range for the previous three candles.
- In the NR7 Scanner, the loop iterates through historical data with a range of 6 to len(historical_data) to calculate the trading range for the previous six candles.
- This adjustment is made to specifically identify Narrow Range 7 (NR7) candles, which require considering the narrowest range among the previous six days.
- NR7 Criteria:
- In the NR4 Scanner, the code checks if the current candle has the narrowest range among the previous three days to detect NR4 candles.
- In the NR7 Scanner, the code checks if the current candle has the narrowest range among the previous six days to detect NR7 candles.
- The minimum trading range is calculated using the
min(trading_ranges)function, and if the current candle has the narrowest range among the previous six, it is considered an NR7 candle.
- Output Message:
- In both scanners, when an NR4 or NR7 candle is detected, a message is printed indicating the pattern and the date on which it occurred for the specific stock.
- The message format is “NR4 Candle detected for {symbol} on {candle[‘date’]}” for the NR4 Scanner and “NR7 Candle detected for {symbol} on {candle[‘date’]}” for the NR7 Scanner.
These changes in the NR7 Scanner enable it to specifically search for Narrow Range 7 (NR7) candles by considering the narrowest range among the previous six days and reporting the date of occurrence for each stock symbol in the symbol_list, similar to how NR4 candles are detected in the NR4 Scanner.