@Meng-Xiaofeng @backtrader
Setting period value in FindFirstIndexHighest is static way. What if i want to achieve in a dynamic way (it can be more than the specified period, if used)?

def next(self):
    self.lines.CDLDARKCLOUDCOVER[0] = talib.CDLDARKCLOUDCOVER(self.data.open, self.data.high, self.data.low, self.data.close, penetration=0.1)

Error -
File "/Users/ayushsomani/PycharmProjects/pythonProject/OHLCBackTesting.py", line 61, in next
self.lines.CDLDARKCLOUDCOVER[0] = talib.CDLDARKCLOUDCOVER(self.data.open, self.data.high, self.data.low, self.data.close, penetration=0.1)
File "/Users/ayushsomani/PycharmProjects/pythonProject/venv/lib/python3.8/site-packages/talib/init.py", line 27, in wrapper
return func(*args, **kwargs)
TypeError: Argument 'open' has incorrect type (expected numpy.ndarray, got LineBuffer)

Approach 1 -
I used the indexing but again an error is raised.

def next(self):
    self.lines.CDLDARKCLOUDCOVER[0] = talib.CDLDARKCLOUDCOVER(self.data.open[0], self.data.high[0], self.data.low[0], self.data.close[0], penetration=0.1)

File "/Users/ayushsomani/PycharmProjects/pythonProject/OHLCBackTesting.py", line 61, in next
self.lines.CDLDARKCLOUDCOVER[0] = talib.CDLDARKCLOUDCOVER(self.data.open[0], self.data.high[0], self.data.low[0], self.data.close[0], penetration=0.1)
File "/Users/ayushsomani/PycharmProjects/pythonProject/venv/lib/python3.8/site-packages/talib/init.py", line 27, in wrapper
return func(*args, **kwargs)
TypeError: Argument 'open' has incorrect type (expected numpy.ndarray, got float)

Approach 2 -
If I use these indicators using bt.talib, there is some issue in the timeperiod. IMO, the CDLDARKCLOUDCOVER just compares the current bar with the previous bar. When I use self.CDLDARKCLOUDCOVER = bt.talib.CDLDARKCLOUDCOVER(self.data.open, self.data.high, self.data.low, self.data.close, penetration=0.1), it is skipping first 11 bars data. I am not getting the behaviour of this Indicator (CDLDARKCLOUDCOVER).

SBIN.csv

@run-out
This is my CSV file.

@run-out
I am not getting the desired output.

Code Snippet -

from future import (absolute_import, division, print_function,
unicode_literals)
from datetime import datetime
import os.path
import sys
import backtrader as bt
import pandas as pd
import math

ticker_list = ['SBIN']

class DynamicHighest(bt.Indicator):
lines = ('firsthighindex','periodline',)
params = dict(minperiod=3, maxperiod=20)

def __init__(self):
    self.addminperiod(self.p.minperiod)
    self.l.firsthighindex = bt.ind.FindFirstIndexHighest(self.datas[0].high, period=self.p.maxperiod)

def next(self):
    if self.datas[0].high[0] < self.datas[0].high[-int(self.l.firsthighindex[0])]:
        self.l.periodline[0] = self.l.firsthighindex[0]

class MyStrategy(bt.Strategy):
params = dict(bearish=-100, bullish=100)

def log(self, txt, dt=None):
    dt = dt or self.datas[0].datetime.date(0)
    print('{0}, {1}'.format(dt.isoformat(), txt))

def __init__(self):
    self.dataopen = self.datas[0].open
    self.datahigh = self.datas[0].high
    self.datalow = self.datas[0].low
    self.dataclose = self.datas[0].close
    self.CDLENGULFING = bt.talib.CDLENGULFING(self.datas[0].open, self.datas[0].high, self.datas[0].low, self.datas[0].close)
    self.CDLDARKCLOUDCOVER = bt.talib.CDLDARKCLOUDCOVER(self.datas[0].open, self.datas[0].high, self.datas[0].low, self.datas[0].close)
    self.dyn_highest = DynamicHighest(self.datas[0])

def next(self):
    if math.isclose(self.dataopen[0], self.datahigh[0], abs_tol=0.2):
        #Minimum Criteria to be Considered
        if self.datahigh[0] > self.datahigh[-1]:
            if (self.CDLENGULFING[0] == self.p.bearish or self.CDLDARKCLOUDCOVER[0] == self.p.bearish):
                if self.dyn_highest.l.periodline[0] >= 3:
                    self.log(' SELL CREATED AT PRICE: , %.2f with %.2f number of days taken out.' % (self.dataclose[0],abs(self.dyn_highest.l.periodline[0])))

if name == 'main':
for ticker in ticker_list:
print('Ticker: %s' % ticker)
cerebro = bt.Cerebro()
cerebro.broker.set_cash(10000)

    filename = '%s.csv' % ticker
    #modpath = os.path.dirname('/Users/ayushsomani/Desktop/BANKNIFTY/')
    datapath = os.path.join('/Users/ayushsomani/Desktop/BANKNIFTY/', filename)

    if not os.path.isfile(datapath):
        print('File: %s not found' % filename)
        sys.exit()

    dateparse = lambda date: datetime.strptime(date, '%Y-%m-%d')
    data = pd.read_csv(datapath, index_col='Date', parse_dates=True, date_parser=dateparse)
    datafeed = bt.feeds.PandasData(dataname=data)

    cerebro.adddata(datafeed)
    print('Starting Portfolio Value: %.2f' % cerebro.broker.get_value())
    cerebro.addstrategy(MyStrategy)
    cerebro.run()
    print('Final Portfolio Value: %.2f' % cerebro.broker.get_value())

Output -
Ticker: SBIN
Starting Portfolio Value: 10000.00
2018-11-19, SELL CREATED AT PRICE: , 288.15 with 9.00 number of days taken out.
2018-12-04, SELL CREATED AT PRICE: , 282.55 with 19.00 number of days taken out.
2020-06-24, SELL CREATED AT PRICE: , 184.60 with 12.00 number of days taken out.
Final Portfolio Value: 10000.00

On Chart (https://in.tradingview.com/chart/K307Cbrw/), we can clearly see that 04/12/2018 High is broken on 30/11/2018 but the Output is showing that it took 19 bars to break this high. Hope, you understood my query what I am trying to achieve.

@dasch
What does exactly FindFirstIndexHighest does (if I use it calculating count of those bars)?

@dasch This is my Code -

from datetime import datetime
import os.path
import sys
import backtrader as bt
import pandas as pd
import math

ticker_list = ['SBIN']

class DynamicHighest(bt.Indicator):
lines = ('periodline',)
params = dict(minperiod=3)

def __init__(self):
    self.addminperiod(self.p.minperiod)

def next(self):
    pass

class MyStrategy(bt.Strategy):
params = dict(bearish=-100, bullish=100)

def log(self, txt, dt=None):
    dt = dt or self.datas[0].datetime.date(0)
    print('{0}, {1}'.format(dt.isoformat(), txt))

def __init__(self):
    self.dataopen = self.datas[0].open
    self.datahigh = self.datas[0].high
    self.datalow = self.datas[0].low
    self.dataclose = self.datas[0].close
    self.CDLENGULFING = bt.talib.CDLENGULFING(self.datas[0].open, self.datas[0].high, self.datas[0].low, self.datas[0].close)
    self.CDLDARKCLOUDCOVER = bt.talib.CDLDARKCLOUDCOVER(self.datas[0].open, self.datas[0].high, self.datas[0].low, self.datas[0].close)
    self.dyn_highest = DynamicHighest(self.data.high)

def next(self):
    if math.isclose(self.dataopen[0], self.datahigh[0], abs_tol=0.2):
        #Minimum Criteria to be Considered
        if self.datahigh[0] > self.datahigh[-1]:
            """print('DATE: '+str(self.date(0))+' CDLENGULFING: '+str(self.CDLENGULFING[0])+' CDLDARKCLOUDCOVER: '+str(self.CDLDARKCLOUDCOVER[0]))"""
            if (self.CDLENGULFING[0] == self.p.bearish or self.CDLDARKCLOUDCOVER[0] == self.p.bearish):
                self.log(' SELL CREATED AT PRICE: , %.2f' % self.dataclose[0])

if name == 'main':
for ticker in ticker_list:
print('Ticker: %s' % ticker)
cerebro = bt.Cerebro()
cerebro.broker.set_cash(10000)

    filename = '%s.csv' % ticker
    #modpath = os.path.dirname('/Users/ayushsomani/Desktop/BANKNIFTY/')
    datapath = os.path.join('/Users/ayushsomani/Desktop/BANKNIFTY/', filename)

    if not os.path.isfile(datapath):
        print('File: %s not found' % filename)
        sys.exit()

    dateparse = lambda date: datetime.strptime(date, '%Y-%m-%d')
    data = pd.read_csv(datapath, index_col='Date', parse_dates=True, date_parser=dateparse)
    datafeed = bt.feeds.PandasData(dataname=data)
    cerebro.adddata(datafeed)
    print('Starting Portfolio Value: %.2f' % cerebro.broker.get_value())
    cerebro.addstrategy(MyStrategy)
    cerebro.run()
    print('Final Portfolio Value: %.2f' % cerebro.broker.get_value())

I am unable to write the logic in my Created Indicator (DynamicHighest). I tried various approaches but couldn't get the success. Moreover, some of the rows are skipped when I run my Cerebro. My CSV starts on Date - 17/09/18 but when I debugged it is processing from Date - 04/10/18. Why so?

CSV File

Please refer to this example

The 12th Feb bar has met the condition and now I need to check that it's has taken out high of some defined period, which in this case is from 15th Jan to 11th Feb. So, I need to count how many such bars are there in this.

Re: Indicator that checks if the current candle high (as soon as a condition is met) breaks the previous days high (over a specific period ) or not

Please refer to this example.

The 12th Feb bar has met the condition and now I need to check that it's has taken out high of some defined period, which in this case is from 15th Jan to 11th Feb. So, I need to count how many such bars are there in this.

I am making an Indicator that calculates how many previous days (period is dynamic i.e. 3, 4, 5, 10 and 20) high is taken out as soon as we met a condition on a bar. I used Highest (MaxN) to find the High in those specified periods (i.e. 3, 4, 5, 10 and 20) in next of my Indicator and stored the results in Lines. Then, I compared them in next of my Strategy with the bar's high (the one which satisfies the condition). But I am not getting the desired results even though on charts I can point out such data points. Please help !!
@run-out @dasch @backtrader @vladisld

I am stuck on how to calculate the no. of previous days/candles 'High' is taken out, as soon as we encounter a Open=High day/candle. There is no fixed period (no. of days/candles). No. of such previous days/candles are dynamic but at-least 1. I am confused in writing the code as I don't know where to check this (i.e. if i make an Indicator, should I check it there or in my Strategy class). Moreover, I am confused with the flow of backtrader. I read the documentation but still it's quite confusing.