Category Archives: Python

Trading the Equity Curve – Part 1 of N?

Only Trade the Best Segments of the Equity Curve – Cut Out Drawdown and Take Advantage of Run Ups! Really?

Equity curve feedback has been around for many years and seems highly logical, but one can’t get an industry-wide agreement on its benefit.  The main problem is to know when to turn trading off and then back on as you track the equity curve.  The most popular approach is to use a moving average of the equity curve to signal system participation.   When the equity curve moves below 30, 60, or 90 period-moving average of equity, then just turn it off and wait until the curve crosses back above the average.  This approach will be investigated in Part 2 of this series.  Another approach is to stop trading once the curve enters a drawdown that exceeds a certain level and then start back up once the equity curve recovers.  In this post, this method will be investigated.

Programmers Perspective

How do you go about programming this tool to start with.  There are probably multiple ways of accomplishing this task, but the two I have most often observed were the two pass process and the inline simultaneous tracking of the synthetic and actual equity curves.  The two pass process generates an unadulterated equity curve and stores the equity and trades either in memory or in a file.  The second part of the process monitors the external equity curve along with the external trades synchronously and while trading is turned on, the trades are executed as they occur chronologically.  When trading is turned off, the synthetic equity curve and trades are processed along the way.   The second method is to create, which I have coined (maybe others too!), a synthetic equity curve and synthetic trades.  I have done this in my TradingSimula_18 software by creating a SynthTrade Class.  This class contains all the properties of every trade and in turn can use this information to create a synthetic equity curve.  The synthetic equity curve and trades are untouched by the real time trading.

Start Simple

The creation of an equity curve monitor and processor is best started using a very simple system.  One market algorithm that enters and exits on different dates, where pyramiding and scaling in or out are not allowed.  The first algorithm that I tested was a mean reversion system where you buy after two consecutive down closes followed by an up close and then waiting one day.  Since I tested the ES over the past 10 years you can assume the trend is up. I must admit that the day delay was a mistake on my behalf.  I was experimenting with a four bar pattern and somehow forgot to look at the prior day’s action.  Since this is an experiment it is OK!

if marketPosition <> 1 and 
(c[2] < c[3] and c[3] < c[4] and c[1]  > =  c[2]) then 
	buy next bar at open;

//The exit is just as simple - 
//get out after four days (includeing entry bar) on the next bars open - no stops or profit objectives.  

If barsSinceEntry > 2 then sell next bar at open;
Simple Strategy to test Synthetic Trading Engine

Here is the unadulterated equity curve using $0 for execution costs.

Non adjusted equity curve of our simple mean reversion system. Wait for a pull back and then a rally before entering.

The Retrace and Recover Method

In this initial experiment, trading is suspended once you reach a draw down of 10% from the peak of the equity curve and then resumes trading once a rally of 15% of the subsequent valley.  Here is an intriguing graphic.

Green means ON. Red means OFF. The lower curve is the resultant curve.

I did this analysis by hand with Excel and it is best case scenario.  Meaning that when trading is turned back on any current synthetic position is immediately executed in the real world.  This experiment resulted in nearly the same drawdown but a large drop in overall equity curve growth – $75K.

Put the Synthetic Equity Curve Engine to the Test

Now that I had the confirmed results of the experiment, I used them as the benchmark against my TS-18 Synthetic Trade Engine.  But before I installed the Equity Curve algorithm, I needed to make sure my synthetic trades lined up exactly with the real equity curve.  The synthetic curve should align 100% with the real equity curve.  If it doesn’t, then there is a problem.  This is another reason to start with a simple trading strategy.

Take a look here where I print out the Synthetic Equity curve on  a daily basis and compare it with the end result of the analysis.

Synth. matches Reality

Now let’s see if it worked.

Testing with Synth. Equity Curve Trading Turned ON!

The equity curves are very similar.  However, there is a difference and this is caused by how one re-enters after trading is turned back on.  In this version I tested waiting for a new trade signal which might take a few days.  You could re-enter in three different ways:

  1. Automatically enter synthetic position on the next bar’s open
  2. Wait for a new trade signal
  3. Enter immediately if you can get in at a better price

Using the 10% Ret. and 15% Rec. algorithm didn’t help at all.  What if we test 10% and 10%.

10% Ret. and 10% Rec.

Now that performed better – more profit and less draw down.  Now that I have the synthetic engine working on simple algorithms we can do all sorts of equity curve analysis.  In the next installment in this series I will make sure the TS-18 Synthetic Engine can handle more complicated entry and exit algorithms.  I have already tested a simple longer term trend following strategy on a medium sized portfolio and the synthetic engine worked fine.  The retracement/recovery algorithm at 10%/15% did not work and I will go into the “whys” in my next post.

Another Good Year For Trend Following

Take a Look at the Last Two Years

Simple Donchian on a one contract basis.  $100 Commission/slippage.  Tested from 2000 thru December 31, 2021.  Do you see why most trend followers failed after the 2008 monstrous year.   Many funds caught the 2008 move and more funds were added soon thereafter.  Promises of similar performance came to fruition in 2011.  This kept much of the “new money” on the board.  However, reality set in and weak handed funds left for greener pastures.  Those that stuck it out were rewarded in 2014.  The trend drought of 2014 -2019 eroded most of the confidence in managed futures.  The rationalization that limited resources would eventually rise in price sounded good initially, but then fell on deaf ears after months of draw down.  Well known CTAs and hedge funds shut their doors forever.   The long awaited promise of 2008 came in the form of a pandemic – but it was too late.   Maybe now the deluge that ended the drought will persevere (hopefully not in the form of a pandemic) into the future.  Prices do not need to rise endlessly, but they need to move one direction or another without many hiccups.   

Simple Donchian Caught Most of the Commodities Up Moves

Which Sectors Pushed this Curve through the Roof

These reports were generated by my Python based Trading Simula-18 using Pinnacle continuous data – rollover triggered by date.  This is my new sector analysis report where I graph the last four years performance.  The tabular data is for the entire 21 year history.  The best sectors were energy, grains, financials and metals.  Lumber was extraordinary

Sector Analysis Report
Currency   -------------------------------------
BN           -28012      44681 
SN           -26925      55337 
AN             6560      34350 
DX            16284      24387 
FN            67463      31737 
JN           -22212      50362 
CN           -25355      44110 
Totals:      -12198     141445 
Currency   Last 4 Years    ---------------------
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Energies   -------------------------------------
ZU           180750      38330 
ZH           155696      85541 
ZN            70630      74400 
ZB           131874      66651 
Totals:      538951     154434 
Energies   Last 4 Years    ---------------------
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Metals     -------------------------------------
ZG           -17070      43540 
ZI            68395     146885 
ZK           101888      29475 
ZP            82885      27600 
ZA           174955      83910 
Totals:      411052     166703 
Metals     Last 4 Years    ---------------------
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Grains     -------------------------------------
ZS            79175      20312 
ZW           -43438      51975 
ZC             5238      26688 
ZL            13248      24588 
ZM            29860      28810 
Totals:       84083      88850 
Grains     Last 4 Years    ---------------------
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Financials -------------------------------------
US            35991      24959 
TY             -350      29175 
TU             1473      23969 
EC             4700       9650 
Totals:       41813      56453 
Financials Last 4 Years    ---------------------
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Softs      -------------------------------------
SB            25927      15035 
KC           -49775      94069 
CC           -72140      76660 
CT            16785      45470 
Lumber       218513      51745 
JO             2588      15760 
Totals:      141898     128540 
Softs      Last 4 Years    ---------------------
                                            | ||
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     |  ||||||||||| |      |||||||||||||||||||||
Meats      -------------------------------------
ZT           -29940      57680 
ZZ            38480      15080 
ZF            18413      57550 
Totals:       26952      66515 
Meats      Last 4 Years    ---------------------
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How Do You Program this in Python

Here is the module for TS-18.  There is a little extra code to keep track of sectors in case you want to limit sector exposure.  However, this code takes every trade on a one contract basis.  This code reflects my latest version of TS-18, which will be released shortly.

#  Define Long, Short, ExitLong and ExitShort Levels - mind your indentations
            buyLevel = highest(myHigh,40,curBar,1)
            shortLevel = lowest(myLow,40,curBar,1)
            longExit = lowest(myLow,20,curBar,1)
            shortExit = highest(myHigh,20,curBar,1)
            ATR = sAverage(myTrueRange,30,curBar,1)
            stopAmt = 2000/myBPV

            ATR = sAverage(myTrueRange,30,curBar,1)

            posSize = 1
            mmLxit = 99999999
            mmSxit = -99999999
            if mp == 1 : mmLxit = entryPrice[-1] - stopAmt
            if mp ==-1 : mmSxit = entryPrice[-1] + stopAmt

#  Long Exit
            if mp == 1 and myLow[curBar] <= mmLxit and mmLxit > longExit and barsSinceEntry > 1:
                price = min(myOpen[curBar],mmLxit)
                tradeName = "LxitMM"
                numShares = curShares
                exitPosition(price, curShares, tradeName, sysMarkDict)
#  Long Exit
            if mp == 1 and myLow[curBar] <= longExit and barsSinceEntry > 1:
                price = min(myOpen[curBar],longExit)
                tradeName = "Lxit"
                numShares = curShares
                exitPosition(price, curShares, tradeName, sysMarkDict)
#  Short Exit
            if mp == -1 and myHigh[curBar] >= shortExit and barsSinceEntry > 1:
                price = max(myOpen[curBar],shortExit)
                tradeName = "Sxit"
                numShares = curShares
                exitPosition(price, curShares, tradeName, sysMarkDict)
#  Short Exit
            if mp == -1 and myHigh[curBar] >= entryPrice[-1] + stopAmt and barsSinceEntry > 1:
                price = max(myOpen[curBar],entryPrice[-1] + stopAmt)
                tradeName = "SxitMM"
                numShares = curShares
                exitPosition(price, curShares, tradeName,sysMarkDict)
#  Long Entry
            if myHigh[curBar] >= buyLevel and mp !=1:
                price = max(myOpen[curBar],buyLevel)
                tradeName = "Simple Buy"
                numShares = posSize
#  Short Entry
            if myLow[curBar] <= shortLevel and mp !=-1 :
                price = min(myOpen[curBar],shortLevel)
                if mp == 0 : sectorTradesTodayList[curSector] +=1
                tradeName = "Simple Sell"
                numShares = posSize
                enterShortPosition(price, numShares, tradeName, sysMarkDict)
Python within Trading Simula-18

Turn of the Month Trading Strategy [Stock Indices Only]

The System

This system has been around for several years.  Its based on the belief that fund managers start pouring money into the market near the end of the month and this creates momentum that lasts for just a few days.  The original system states to enter the market on the close of the last bar of the day if the its above a certain moving average value.  In the Jaekle and Tomasini book, the authors describe such a trading system.  Its quite simple, enter on the close of the month if its greater than X-Day moving average and exit either 4 days later or if during the trade the closing price drops below the X-Day moving average.

EasyLanguage or Multi-Charts Version

Determining the end of the month should be quite easy -right?  Well if you want to use EasyLanguage on TradeStation and I think on Multi-Charts you can’t sneak a peek at the next bar’s open to determine if the current bar is the last bar of the month.  You can try, but you will receive an error message that you can’t mix this bar on close with next bar.  In other words you can’t take action on today’s close if tomorrow’s bar is the first day of the month.  This is designed, I think, to prevent from future leak or cheating.  In TradeStation the shift from backtesting to trading is designed to be a no brainer, but this does provide some obstacles when you only want to do a backtest.

LDOM function – last day of month for past 15 years or so

So I had to create a LastDayOfMonth function.  At first I thought if the day of the month is the 31st then it is definitely the last bar of the month.  And this is the case no matter what.  And if its the 30th then its the last day of the month too if the month is April, June, Sept, and November.  But what happens if the last day of the month falls on a weekend.  Then if its the 28th and its a Friday and the month is blah, blah, blah.  What about February?  To save time here is the code:

Inputs: movAvgPeriods(50);
vars: endOfMonth(false),theDayOfWeek(0),theMonth(0),theDayOfMonth(0),isLeapYear(False);

endOfMonth = false;
theDayOfWeek = dayOfWeek(date);
theMonth = month(date);
theDayOfMonth = dayOfMonth(date);
isLeapYear = mod(year(d),4) = 0;

// 29th of the month and a Friday
if theDayOfMonth = 29 and theDayOfWeek = 5 then 
	endOfMonth = True;
// 30th of the month and a Friday
if theDayOfMonth = 30 and theDayOfWeek = 5 then 
	endOfMonth = True;
// 31st of the month 	
if theDayOfMonth = 31 then 
	endOfMonth = True;
// 30th of the month and April, June, Sept, or Nov
if theDayOfMonth = 30 and (theMonth=4 or theMonth=6 or theMonth=9 or theMonth=11) then 
	endOfMonth = True;
// 28th of the month and February and not leap year
if theDayOfMonth = 28 and theMonth = 2 and not(isLeapYear)  then 
	endOfMonth = True;
// 29th of the month and February and a leap year or 28th, 27th and a Friday	
if theMonth = 2 and isLeapYear then
	If theDayOfMonth = 29 or ((theDayOfMonth = 28 or theDayOfMonth = 27) and theDayOfWeek = 5) then 
	endOfMonth = True;	
// 28th of the month and Friday and April, June, Sept, or Nov
if theDayOfMonth = 28 and (theMonth = 4 or theMonth = 6 or 
	theMonth = 9 or theMonth =11) and theDayOfWeek = 5 then
	endOfMonth = True;
// 27th, 28th of Feb and Friday	
if theMonth = 2 and theDayOfWeek = 5 and theDayOfMonth = 27 then
	endOfMonth = True;
// 26th of Feb and Friday and not LeapYear
if theMonth = 2 and theDayOfWeek = 5 and theDayOfMonth = 26 and not(isLeapYear) then
	endOfMonth = True;	
// Memorial day adjustment
If theMonth = 5 and theDayOfWeek = 5 and theDayOfMonth = 28 then
	endOfMonth = True;
//Easter 2013 adjustment
If theMonth = 3 and year(d) = 113 and theDayOfMonth = 28 then
	endOfMonth = True;
//Easter 2018 adjustment
If theMonth = 3 and year(d) = 118 and theDayOfMonth = 29 then
	endOfMonth = True;	

if endOfMonth and c > average(c,movAvgPeriods) then	
	Buy("BuyDay") this bar on close;

If C <average(c,movAvgPeriods) then 
	Sell("MovAvgExit") this bar on close;
If BarsSinceEntry=4 then 
	Sell("4days") this bar on close;
Last Day Of Month Function and Strategy

All the code is generic except for the hard code for days that are a consequence of Good Friday.

All this code because I couldn’t sneak a peek at the date of tomorrow.  Here are the results of trading the ES futures sans execution costs for the past 15 years.

Last Day Of Month Buy If C > 50 Day Mavg

What if it did the easy way and executed the open of the first bar of the month.

If c > average(c,50) and month(d) <> month(d of tomorrow) then 
	buy next bar at open;

If  barsSinceEntry >=3 then 
	sell next bar at open;

If marketPosition = 1 and c < average(c,50) then 
	sell next bar at open;
Buy First Day Of Month
First Day of Month If C > 50 Day Mavg

The results aren’t as good but it sure was easier to program.

TradingSimula-18 Version

Since you can use daily bars we can test this with my TradingSimula-18 Python platform.  And we will execute on the close of the month.  Here is the snippet of code that you have to concern yourself with.  Here I am using Sublime Text and utilizing their text collapsing tool to hide non-user code:

Small Snippet of TS-18 Code

This was easy to program in TS-18 because I do allow Future Leak – in other words I will let you sneak a peek at tomorrow’s values and make a decision today.  Now many people might say this is a huge boo-boo, but with great power comes great responsibility.  If you go in with eyes wide open, then you will only use the data to make things easier or even doable, but without cheating.  Because you are only going to cheat yourself.  Its in your best interest do follow the rules.  Here is the line that let’s you leak into the future.

If isNewMonth(myDate[curBar+1])

The curBar is today and curBar+1 is tomorrow.  So I am saying if tomorrow is the first day of the month then buy today’s close.  Here you are leaking into the future but not taking advantage of it.  We all know if today is the last day of the month, but try explaining that to a computer.  You saw the EasyLanguage code.  So things are made easier with future leak, but not taking advantage of .

Here is a quick video of running the TS-18 Module of 4 different markets.


A Quant’s ToolBox: Beautiful Soup, Python, Excel and EasyLanguage

Many Times It Takes Multiple Tools to Get the Job Done

Just like a mechanic, a Quant needs tools to accomplish many programming tasks.  In this post, I use a toolbox to construct an EasyLanguage function that will test a date and determine if it is considered a Holiday in the eyes of the NYSE.

Why a Holiday Function?

TradeStation will pump holiday data into a chart and then later go back and take it out of the database.  Many times the data will only be removed from the daily database, but still persist in the intraday database.  Many mechanical day traders don’t want to trade on a shortened holiday session or use the data for indicator/signal calculations.  Here is an example of a gold chart reflecting President’s Day data in the intra-day data and not in the daily.

Holiday Data Throws A Monkey Wrench Into the Works

This affects many stock index day traders.  Especially if automation is turned on.  At the end of this post I provide a link to my youTube channel for a complete tutorial on the use of these tools to accomplish this task.  It goes along with this post.

First Get The Data

I searched the web for a list of historical holiday dates and came across this:

Historic List of Holidays and Their Dates

You might be able to find this in a easier to use format, but this was perfect for this post.

Extract Data with Beautiful Soup

Here is where Python and the plethora of its libraries come in handy.  I used pip to install the requests and the bs4 libraries.  If this sounds like Latin to you drop me an email and I will shoot you some instructions on how to install these libraries.  If you have Python, then you have the download/install tool known as pip.

Here is the Python code.  Don’t worry it is quite short.

# Created:     24/02/2020
# Copyright:   (c) George 2020
# Licence:     <your licence>

import requests
from bs4 import BeautifulSoup

url = ''
page = requests.get(url)
soup = BeautifulSoup(page.text,'html.parser')
all_tables = soup.findAll('table')
#print (all_tables)
print (len(all_tables))
#print (all_tables[0])
a = list()
b = list()
c = list()
for numTables in range(len(all_tables)-1):
    for rows in all_tables[numTables].find_all('tr'):

for j in range(len(a)-1):
Using Beautiful Soup to Extract Table Data

As you can see this is very simple code.  First I set the variable url to the website where the holidays are located.  I Googled on how to do this – another cool thing about Python – tons of users.  I pulled the data from the website and stuffed it into the page object.  The page object has several attributes (properties) and one of them  is a text representation of the entire page.  I pass this text to the BeautifulSoup library and inform it to parse it with the html.parser.  In other words, prepare to extract certain values based on html tags.  All_tables contains all of the tables that were parsed from the text file using Soup.  Don’t worry how this works, as its not important, just use it as a tool.  In my younger days as a programmer I would have delved into how this works, but it wouldn’t be worth the time because I just need the data to carry out my objective; this is one of the reasons classically trained programmers never pick up the object concept.  Now that I have all the tables in a list I can loop through each row in each table.  It looked liker there were 9 rows and 2 columns in the different sections of the website, but I didn’t know for sure so I just let the library figure this out for me.  So I played around with the code and found out that the first two columns of the table contained the name of the holiday and the date of the holiday.  So, I simply stuffed the text values of these columns in two lists:  a and b.  Finally I print out the contents of the two lists, separated by a hyphen, into the Interpreter window.  At this point I could simply carry on with Python and create the EasyLanguage statements and fill in the data I need.  But I wanted to play around with Excel in case readers didn’t want to go the Python route.  I could have used a powerful editor such as NotePad++ to extract the data from the website in place of Python.  GREP could have done this.  GREP is an editor tool to find and replace expressions in a text file.

Use Excel to Create Actual EasyLanguage – Really!

I created a new spreadsheet.  I used Excel, but you could use any spreadsheet software.   I first created a prototype of the code I would need to encapsulate the data into array structures.  Here is what I want the code to look like:

Arrays: holidayName[300](""),holidayDate[300](0);

holidayName[1]="New Year's Day ";	holidayDate[1]=19900101;
Code Prototype

This is just the first few lines of the function prototype.  But you can notice a repetitive pattern.  The array names stay the same – the only values that change are the array elements and the array indices.  Computers love repetitiveness.  I can use this information a build a spreadsheet – take a look.

Type EasyLanguage Into the Columns and Fill Down!

I haven’t copied the data that I got out of Python just yet.  That will be step 2.  Column A has the first array name holidayName (notice I put the left square [ bracket in the column as well).  Column B will contain the array index and this is a formula.  Column C contains ]=”.  Column D will contain the actual holiday name and Column E contains theThese columns will build the holidayName array.  Columns G throuh K will build the holidayDates array.    Notice column  H  equals column B.  So whatever we do to column B (Index) will be reflected in Column H (Index).  So we have basically put all the parts of the EasyLanguage into  Columns A thru K. 

Excel provides tools for manipulating strings and text.  I will use the Concat function to build my EasyLanguageBut before I can use Concat all the stuff I want to string together must be in a string or text format.  The only column in the first five that is not a string is Column B.  So the first thing I have to do is convert it to text.  First copy the column and paste special as values.  Then go to your Data Tab and select Text To Columns. 

Text To Columns

It will ask if fixed width or delimited – I don’t think it matters which you pick.  On step 3 select text.

Text To Columns – A Powerful Tool

The Text To Columns button will solve 90% of your formatting issues in Excel.    Once you do this you will notice the numbers will be left justified – this signifies a text format.  Now lets select another sheet in the workbook and past the holiday data.

Copy Holiday Data Into Another Spreadsheet

New Year's Day - January 1, 2021
Martin Luther King, Jr. Day - January 18, 2021
Washington's Birthday (Presidents' Day) - February 15, 2021
Good Friday - April 2, 2021
Memorial Day - May 31, 2021
Independence Day - July 5, 2021
Labor Day - September 6, 2021
Thanksgiving - November 25, 2021
Christmas - December 24, 2021
New Year's Day - January 1, 2020
Martin Luther King, Jr. Day - January 20, 2020
Washington's Birthday (Presidents' Day) - February 17, 2020
Good Friday - April 10, 2020
Memorial Day - May 25, 2020
Holiday Output


Data Is In Column A

Text To Columns to the rescue.  Here I will separate the data with the “-” as delimiter and tell Excel to import the second column in Date format as MDY.  

Text To Columns with “-” as the delimiter and MDY as Column B Format

Now once the data is split accordingly into two columns with the correct format – we need to convert the date column into a string.

Convert Date to a String

Now the last couple of steps are really easy.  Once you have converted the date to a string, copy Column A and past into Column D from the first spreadsheet.  Since this is text, you can simply copy and then paste.  Now go back to Sheet 2 and copy Column C and paste special [values] in Column J on Sheet 1.  All we need to do now is concatenate the strings in Columns A thru E for the EasyLanguage for the holidayName array.  Columns G thru K will be concatenated for the holidayDate array.  Take a look.

Concatenate all the strings to create the EasyLanguage

Now create a function in the EasyLanguage editor and name it IsHoliday and have it return a boolean value.  Then all you need to do is copy/paste Columns F and L and the data from the website will now be available for you use.   Here is a portion of the function code.  Notice I declare the holidayNameStr as a stringRef?  I did this so I could change the variable in the function and pass it back to the calling routine.

Inputs : testDate(numericSeries),holidayNameStr(stringRef);

Arrays: holidayName[300](""),holidayDate[300](0);

holidayNameStr = "";

holidayName[1]="New Year's Day ";	holidayDate[1]=19900101;
holidayName[2]="Martin Luther King, Jr. Day ";	holidayDate[2]=19900115;
holidayName[3]="Washington's Birthday (Presidents' Day) ";	holidayDate[3]=19900219;
holidayName[4]="Good Friday ";	holidayDate[4]=19900413;
holidayName[5]="Memorial Day ";	holidayDate[5]=19900528;
holidayName[6]="Independence Day ";	holidayDate[6]=19900704;
holidayName[7]="Labor Day ";	holidayDate[7]=19900903;
holidayName[8]="Thanksgiving ";	holidayDate[8]=19901122;
holidayName[9]="New Year's Day ";	holidayDate[9]=19910101;
holidayName[10]="Martin Luther King, Jr. Day ";	holidayDate[10]=19910121;
holidayName[11]="Washington's Birthday (Presidents' Day) ";	holidayDate[11]=19910218;

// There are 287 holiays in the database.
// Here is the looping mechanism to compare the data that is passed
// to the database

vars: j(0);
IsHoliday = False;
For j=1 to 287
	If testDate = holidayDate[j] - 19000000 then
		holidayNameStr = holidayName[j] + " " + numToStr(holidayDate[j],0);
		IsHoliday = True;
A Snippet Of The Function - Including Header and Looping Mechanism

This was a pretty long tutorial and might be difficult to follow along.  If you want to watch my video, then go to this link.

I created this post to demonstrate the need to have several tools at your disposal if you really want to become a Quant programmer.  How you use those tools is up to you.  Also you will be able to take bits and pieces out of this post and use in other ways to get the data you really need.  I could have skipped the entire Excel portion of the post and just did everything in Python.  But I know a lot of Quants that just love spreadsheets.  You have to continually hone your craft in this business.   And you can’t let one software application limit your creativity.  If you have a problem always be on the lookout for alternative platforms and/or languages to help you solve it.



The Cure for the Common Trend Follower – SOTF Part 2

Clenow’s algorithm is definitely an indicator for the current State of Trend Following (SOTF).  However, the 3 X ATR trailing stop mechanism actually dampens the profit/draw down ratio.  Take a look at this chart.

Battle of Titans

All Trend Following mechanisms have a very common thread in their entry mechanisms.   The thing that separates them is the preemptive exit.  Do you allow the the algorithm to exit on a purely market defined method or do you overlay trade management?  Here the best approach was to let the Bollinger Band system run unfettered; even though it seems somewhat illogical.  Many times  trade management actually increases draw down.   Is there a solution?  What about this – keep risk down by trading a small, yet diverse portfolio of high volume markets and overlay it with a stock index mean reversion algo.  Take a look.

Bollinger Marries ES Reversion


Should’ve, Would’ve , Could’ve.

This could be scaled up.  The mean reversion helped lift  the chart out of the flat and draw down periods of late.  However, the smaller portfolio did OK during this time period too!  Can four or five high volume markets replicate a much larger portfolio?  All tests were carried out with TradingSimula18 – the software that comes with my latest book.

State of Trend Following – Part 1

Clenow’s Trend Following System

Its a new decade! Time to see what’s up with Trend Following.

I am a huge fan of Andreas Clenow’s books, and how he demonstrated that a typical trader could replicate the performance of most large Trend Following CTAs and not pay the 2% / 20% management/incentive combo fees.  So. I felt the system that he described in his book would be a great representation of The State of Trend Following.  At the same time I am going to demonstrate TradingSimula18 (the software included in my latest book).

System Description

Take a look at my last post.  I provide the EasyLanguage and a pretty good description of Clenow’s strategy.

TradingSimula18 Code [Python]

#  Start programming your great trading ideas below here - don't touch stuff above
#  Define Long, Short, ExitLong and ExitShort Levels - mind your indentations
            ATR = sAverage(myTrueRange,30,curBar,1)
            posSize = 2000/(ATR*myBPV)
            posSize = max(int(posSize),1)
            posSize = min(posSize,20)
            avg1 = xAverage(myClose,marketVal5[curMarket],50,curBar,1)
            avg2 = xAverage(myClose,marketVal6[curMarket],100,curBar,1)
            marketVal5[curMarket] = avg1
            marketVal6[curMarket] = avg2
            donchHi = highest(myHigh,50,curBar,1)
            donchLo = lowest(myLow,50,curBar,1)

            if mp == 1 : marketVal1[curMarket] = max(marketVal1[curMarket],myHigh[curBar-1]- 3 * ATR)
            if mp ==-1 : marketVal2[curMarket] = min(marketVal2[curMarket],myLow[curBar-1]+ 3 * ATR)
#  Long Entry
            if avg1 > avg2 and myHigh[curBar-1] == donchHi and mp !=1:
                price = myOpen[curBar]
                tradeName = "TFClenowB";numShares = posSize
                marketVal1[curMarket] = price - 3 * ATR
                if mp <= -1:
                profit,curShares,trades = bookTrade(entry,buy,price,myDate[curBar],tradeName,numShares)
                barsSinceEntry = 1
#  Long Exit
            if mp == 1 and myClose[curBar-1] <= marketVal1[curMarket] and barsSinceEntry > 1:
                price = myOpen[curBar]
                tradeName = "Lxit";numShares = curShares
                profit,curShares,trades = bookTrade(exit,ignore,price,myDate[curBar],tradeName,numShares)
                todaysCTE = profit;barsSinceEntry = 0
#  Short Entry
            if avg1 < avg2 and myLow[curBar-1] == donchLo and mp !=-1:
                price = myOpen[curBar];numShares = posSize
                marketVal2[curMarket] = price + 3 * ATR
                if mp >= 1:
                tradeName = "TFClenowS"
                profit,curShares,trades = bookTrade(entry,sell,price,myDate[curBar],tradeName,numShares)
                barsSinceEntry = 1
#  Short Exit
            if mp == -1 and myClose[curBar-1] >= marketVal2[curMarket] and barsSinceEntry > 1:
                price = myOpen[curBar]
                tradeName = "Sxit"; numShares = curShares
                profit,curShares,trades = bookTrade(exit,ignore,price,myDate[curBar],tradeName,numShares)
                todaysCTE = profit;barsSinceEntry = 0
# - Do not change code below - trade, portfolio accounting - our great idea should stop here
TradingSimula18 Python System Testing Environment

I am going to go over this very briefly.   I know that many of the readers of my blog have attempted to use Python and the various packages out there and have given up on it.  Quantopia and QuantConnect are great websites, but I feel they approach back-testing with a programmer in mind.  This was the main reason I created TS-18 – don’t get me wrong its not a walk in the park either, but it doesn’t rely on external libraries to get the job done.  All the reports I show here are generated from the data created solely by TS-18.  Plus it is very modular – Step 1 leads to Step2 and on and on.   Referring to the code I calculate the ATR (average true range) by calling the simple average function sAverage.  I pass it myTrueRanges, 30, curBar and 1.   I am looking for the average true range over the last 30 days.  I then move onto my position sizing – posSize = $2,000 / ATR in $s.  PosSize must fit between 1 and 20 contracts.  The ATR calculation can get rather small for some markets and the posSize can get rather large.  Avg1 and Avg2 are exponential moving averages of length 50 and 100DonchHi and donchLo are the highest high and lowest low of the past 50 days.   If mp == 1 (long position) then a trailing stop (marketVal1) is set to whichever is higher – the current marketVal1 or the yesterday’s High – 3 X ATR;  the trailing stop tracks new intra-trade highs.  The trailing stop for the short side, marketVal2 is calculated in a similar manner, but low prices are used as well as a positive offset of 3 X ATR.  

Now the next section of code is quite a bit different than say EasyLanguage, but parallels some of the online Python paradigms. Here you must test the current bar’s extremes against the donchHi if you are flat and marketVal1 (the trailing stop variable) if you are long.  If flat you also test the low of the bar against donchLo.  The relationship between avg1 and avg2 are also examined.  If the testing criteria is true, then its up to you to assign the correct price, posSize and tradeName.  So you have four independent if-then constructs:

  • Long Entry – if flat test to see if a long position should be initiated
  • Long Exit – if Long then test to see if a liquidation should be initiated
  • Short Entry – if flat test to see if a short position should be initiated
  • Short Exit – if Short then test to see if a liquidation should be initiated

That’s it – all of the other things are handled by TS-18.  Now that I have completely bored you out of your mind, let’s move onto some results.

Results from 2000 – risking $2,000 per trade:

Roller Coaster Ride for most CTAs, Last one out turn off the lights!

Sector Performance from 2000

Sector Performance from 2000

From this chart it doesn’t make much sense to trade MEATS, SOFTS or GRAINS with a Trend Following approach or does it?

In the next post, I will go over the results with more in depth and possibly propose some ideas that might or might not help.  Stay Tuned!


Get My Latest Book-TrendFollowing Systems: A DIY Project – Batteries Included

Just wanted to let you know that my latest book has just been published.

Trend Following Systems: A DIY Project – Batteries Included: Can You Reboot and Fix Yesterday’s Algorithms to Work with Today’s Markets? 

Trend Following Systems: A DIY Project – Batteries Included

This book introduces my new Python back-tester, TradingSimula-18.  It is completely and I mean completely self contained.  All you need is the latest version of Python and you will be up and running trading systems in less than 5 minutes.  Fifteen years of data on 30 futures is included (data from Quandl).  I have included more than 20 scripts that you can test and build on.   This back-tester is different than the one I published in the Ultimate Algorithmic Trading System Toolbox.  It utilizes what I call the horizontal portfolio spanning paradigm.  Instead of sequentially testing different markets in a portfoio:

It process data in the following manner:

This form of testing allows for decisions to be made on a portfolio basis at the end of any historic bar.   Things like inputting portfolio performance into an allocation formula is super simple.  However, this paradigm opens up a lot of different “what-if” scenarios.

  1. What If I Limit 2 Markets Per Sector
  2. What If I Turn Off A Certain Sector
  3. What If I Liquidate The Largest OTE loser
  4. What If I Liquidate The Largest OTE winner
  5. What If I Only Trade The Ten Markets With The Highest ADX Values

All the data and market performance and portfolio performance is right at your fingertips.  Your testing is only limited by your creativity.

The best part is you get to learn raw Python without having to install complicated libraries like SciKit, Numpy or Pandas.  You don’t even need to install distributions of commercial products – like Anaconda.  Don’t get me wrong I think Anaconda is awesome but many times it is overkill.  If you want to do machine learning then that is the way to go.  If you want to test simple Trend Following algorithms and make portfolio level decisions you don’t need a data science application.

There isn’t a complicated interface to learn.  Its all command line driven from Python’s IDLE.  90% of the source code is revealed for the back-testing software.  Its like one of those see-thru calculators.  You see all the circuits and semiconductors, but in Python.  So you will need to flow through the code to get to the sections that pertain to your test.  Here is a small sample of how you set up the testing parameters for a Donchian Script.


#   If you want to ignore a bunch of non-eseential stuff then
#      S C R O L L   A L M O S T  H A L F   W A Y  D O W N
#-------------------------------------------------------------------------------- - programmed by George Pruitt
#Built on the code and ideas from "The Ultimate Algorithmic Tradins System T-Box"
#Code is broken into sections
#Most sections can and should be ignored
#Each trading algorithm must be programmed with this template
#This is the main entry into the platform
#Import Section - inlcude functions, classes, variables from external modules
# --- Do  not change below here
from getData import getData
from equityDataClass import equityClass
from tradeClass import tradeInfo
from systemMarket import systemMarketClass
from indicators import highest,lowest,rsiClass,stochClass,sAverage,bollingerBands
from indicators import highest,lowest,rsiClass,stochClass,sAverage,bollingerBands,\
from portfolio import portfolioClass
from systemAnalytics import calcSystemResults
from utilityFunctions import getDataAtribs,getDataLists,roundToNearestTick,calcTodaysOTE
from utilityFunctions import setDataLists,removeDuplicates
from portManager import portManagerClass,systemMarkTrackerClass
from positionMatrixClass import positionMatrixClass
from barCountCalc import barCountCalc

from sectorClass import sectorClass, parseSectors, numPosCurrentSector,getCurrentSector
# Pay no attention to these two functions - unless you want to
def exitPos(myExitPrice,myExitDate,tempName,myCurShares):
    global tradeName,entryPrice,entryQuant,exitPrice,numShares,myBPV,cumuProfit
    if mp < 0:
        trades = tradeInfo('liqShort',myExitDate,tempName,myExitPrice,myCurShares,0)
        profit = trades.calcTradeProfit('liqShort',mp,entryPrice,myExitPrice,entryQuant,myCurShares) * myBPV
        profit = profit - myCurShares *commission;trades.tradeProfit = profit;cumuProfit += profit
        trades.cumuProfit = cumuProfit
    if mp > 0:
        trades = tradeInfo('liqLong',myExitDate,tempName,myExitPrice,myCurShares,0)
        profit = trades.calcTradeProfit('liqLong',mp,entryPrice,myExitPrice,entryQuant,myCurShares) * myBPV
        profit = profit - myCurShares * commission;trades.tradeProfit = profit;cumuProfit += profit
        trades.cumuProfit = cumuProfit
    curShares = 0
    for remShares in range(0,len(entryQuant)):curShares += entryQuant[remShares]
    return (profit,trades,curShares)

def bookTrade(entryOrExit,lOrS,price,date,tradeName,shares):
    global mp,commission,totProfit,curShares,barsSinceEntry,listOfTrades
    global entryPrice,entryQuant,exitPrice,numShares,myBPV,cumuProfit
    if entryOrExit == -1:
        profit,trades,curShares = exitPos(price,date,tradeName,shares);mp = 0
        profit = 0;curShares = curShares + shares;barsSinceEntry = 1;entryPrice.append(price);entryQuant.append(shares)
        if lOrS == 1:mp += 1;trades = tradeInfo('buy',date,tradeName,entryPrice[-1],shares,1)
        if lOrS ==-1:mp -= 1;trades = tradeInfo('sell',date,tradeName,entryPrice[-1],shares,1)

dataClassList = list()

marketMonitorList,masterDateList,masterDateGlob,entryPrice = ([] for i in range(4))
buy = entry = 1; sell = exit = -1; ignore = 0;
entryQuant,exitQuant,trueRanges,myBPVList = ([] for i in range(4))
myComNameList,myMinMoveList,systemMarketList = ([] for i in range(3))
cond1,cond2,cond3,cond4 = ([] for i in range(4))
marketVal1,marketVal2,marketVal3,marketVal4 = ([] for i in range(4))
portManager = portManagerClass();marketList = getData();portfolio = portfolioClass()
numMarkets = len(marketList);positionMatrix = positionMatrixClass();positionMatrix.numMarkets = numMarkets
firstMarketLoop = True

# Set up algo parameters here
startTestDate = 20100101 #must be in yyyymmdd
stopTestDate = 20190228 #must be in yyyymmdd
rampUp = 100 # need this minimum of bars to calculate indicators
sysName = 'Donch-MAX2NSect' #System Name here
initCapital = 500000
commission = 100
Ignore Most Of This Code

Everything is batched processed: set up, pick market or portfolio, run.  Then examine all of the reports.  Here is an example of the sector analysis report.

          Total Profit  Max DrawDown
Currency    -------------------------------
BP           -14800      19062 
SF            -8600      53575 
AD             4670      11480 
DX            10180      10279 
EC            -9000      16775 
JY            10025      18913 
CD           -19720      21830 
Totals:      -27245      69223
Energies    -------------------------------
CL           -40400      55830 
HO            80197      23382 
NG           -14870      28920 
RB           -45429      61419 
Totals:      -20502      75957
Metals      -------------------------------
GC            27210      36610 
SI            -1848       2389 
HG            -2402       2438 
PL           -16750      25030 
PA            27230      38615 
Totals:       33440      61472
Grains      -------------------------------
S_            27312       9088 
W_           -25538      32600 
C_            -1838      12212 
BO            -8460       9544 
SM              390      11250 
RR            -1390      12060 
Totals:       -9523      34135
Financials  -------------------------------
US            29488      18375 
TY              969      12678 
TU            -2020       3397 
FV            -2616       4531 
ED            -4519       4869 
Totals:       21302      30178
Softs       -------------------------------
SB            -1716      19717 
KC            15475      44413 
CC              540       8090 
CT            -8705      35660 
LB            22269      16586 
OJ             4720       8262 
Totals:       32583      57976
Meats       -------------------------------
LC           -18910      24020 
LH           -31270      35640 
FC            14600      25737 
Totals:      -35580      59550
Sector Analysis

Plus I include EasyLanguage for the majority of the scripts.  Of course without the portfolio level management.  I am working on a new website that will support the new book at

Please take a look at my latest book – it would make an awesome Christmas present.


Python Script To Import List of Trades into TradeStation’s EasyLanguage – Sort of

Converting A List of Trades, Dates and Prices Into EasyLanguage Arrays:

As the old saying goes “a picture is worth a thousand words!”  Have you ever been given a list of trades like this:

Sell Short,20010622,1178.50 
Buy to Cover,20010626,1159.75 
Sell Short,20010801,1150.00 
Buy to Cover,20010807,1139.75 
Sell Short,20010814,1129.00 
Buy to Cover,20010816,1117.25 
Sell Short,20011001,976.75 
Buy to Cover,20011004,1016.75 
Sell Short,20011107,1053.00 
Buy to Cover,20011123,1069.50 
Sell Short,20011219,1076.25 
Buy to Cover,20020102,1075.00 
Sell Short,20020129,1067.25 
Buy to Cover,20020131,1046.75 
Sell Short,20020131,1046.75 
Buy to Cover,20020205,1026.75 
Sell Short,20020520,1033.25 
Buy to Cover,20020522,1011.50 
Sell Short,20020731,832.00 
Buy to Cover,20020805,792.50 
Sell Short,20020812,834.00 
Buy to Cover,20020814,811.75 
Sell Short,20020911,838.50 
Buy to Cover,20020913,816.75 
List of Trades : Order, Date, Price

But really wanted to see this:

I have created a small Python script that will take a list of trades like those listed in table above and create the following EasyLanguage:

arrays: DateArr[500](0),TradeArr[500](""),PriceArr[500](0);
Converting list of trades to EasyLanguage

This just creates the arrays that you can use to graph the trades on a chart.  If you are using exact prices you got to make sure your data aligns with the prices in the list of trades.  If you are only entering on the open or the close of the bar then the price array isn’t necessary.

The following Python script will also be helpful if you want to learn how to open a file in csv format, read it into lists, convert it and then save the output to a file.

# Name:        Read csv file via askOpen and save txt file via askSave
# Purpose:     Read the trade metrics from a TradeStation csv format
#              and build arrays from the information to display on charts in
#              TradeStation
# Author:      georg
# Created:     29/08/2018
# Copyright:   (c) georg 2018
import csv
import tkinter as tk
import os.path
from tkinter.filedialog import askopenfilenames
from tkinter.filedialog import asksaveasfilename

tradeType = list()
tradeDate = list()
tradePrice = list()

def main():
    root = tk.Tk()
    files = askopenfilenames(filetypes=(('CSV files', '*.csv'),
                                       ('TXT files', '*.txt')),
                                       title='Select CSV format only!')
    fileList =
    fileListLen = len(fileList)

# make sure you know the format ahead of time
# I know "Buy",20180828,2745.75
    cnt = 0
    for files in range(0,fileListLen):
        head,tail = os.path.split(fileList[files])
        with open(fileList[files]) as f:
            f_csv = csv.reader(f)
            for row in f_csv:
                numCols = len(row)
                cnt += 1

    filename = asksaveasfilename(title="Will Save File with '.txt'",defaultextension=".txt")
#    filename = filename + '.txt'
    target1 = open(filename,'w')
    outString = 'arrays: DateArr[500](0),TradeArr[500](0),PriceArr[500](0);\n'
    for x in range(0,cnt):
        if tradeType[x] == "Sell Short": tradeType[x] = "SS"
        if tradeType[x] == "Buy": tradeType[x] = "B"
        if tradeType[x] == "Buy to Cover": tradeType[x] = "SX"
        if tradeType[x] == "Sell": tradeType[x] = "LX"
        outString = 'DateArr['+str(x)+']='+str(tradeDate[x]-19000000)+';TradeArr['+str(x)+']="'+tradeType[x]+'";PriceArr['+str(x)+']='+str(tradePrice[x])+';\n'

if __name__ == '__main__':
Python Script Open, Read, Convert and Write A File Using TK Dialogs

And here is the EasyLanguage code that will step through the arrays and place the trades accordingly.  I noticed that sometimes two trades could occur on the same bar, but only two and you will notice in the code where I programmed this occurrence.

vars: cnt(0);

If date of tomorrow = DateArr[cnt] then
	print("Inside: ",d," ",dateArr[cnt]);
	If tradeArr[cnt] = "B" then
		buy next bar at PriceArr[cnt] stop;
	If tradeArr[cnt] = "LX" then
		sell next bar at PriceArr[cnt] stop;
		If tradeArr[cnt] = "SS" then
		sellShort next bar at PriceArr[cnt] stop;
	If tradeArr[cnt] = "SX" then
		buyToCover next bar at PriceArr[cnt] stop;
	cnt = cnt + 1;
	If DateArr[cnt] = DateArr[cnt-1] then
		print("two trades same day ",d," ",dateArr[cnt]);
		If tradeArr[cnt] = "B" then
			buy next bar at PriceArr[cnt] stop;
		If tradeArr[cnt] = "LX" then
			sell next bar at PriceArr[cnt] stop;
		If tradeArr[cnt] = "SS" then
	    	print("looking to go short at ",PriceArr[cnt]);
			sellShort next bar at PriceArr[cnt] stop;
		If tradeArr[cnt] = "SX" then
			buyToCover next bar at PriceArr[cnt] stop;
		cnt = cnt + 1;
EasyLanguage Snippet To Execute Trades Stored in Arrays



How to Create a Dominant Cycle Class in Python

John Ehlers used the following EasyLanguage code to calculate the Dominant Cycle in a small sample of data.  If you are interested in cycles and noise reduction, definitely check out the books by John Ehlers – “Rocket Science for Traders” or “Cybernetic Analysis for Stocks and Futures.”  I am doing some research in this area and wanted to share how I programmed the indicator/function in Python.  I refer you to his books or online resources for an explanation of the code.  I can tell you it involves an elegantly simplified approach using the Hilbert Transform.


Inputs:	Price((H+L)/2);

Vars:	Imult(.635),
		Qmult (.338),

If CurrentBar > 8 then begin
	Value1 = Price - Price[7];
 	Inphase = 1.25*(Value1[4]  - Imult*Value1[2]) + Imult*InPhase[3];
//    print(price," ",price[7]," ",value1," ",inPhase," ",Quadrature," ",[-1]," ",[-1])	
//	print(d," ",h," ",l," ",c," ",Value1[4]," ",Imult*Value1[2]," ", Imult*InPhase[3]," ",Inphase);
	Quadrature = Value1[2] - Qmult*Value1 + Qmult*Quadrature[2];
	Re = .2*(InPhase*InPhase[1] + Quadrature*Quadrature[1]) + .8*Re[1];
	Im = .2*(InPhase*Quadrature[1] - InPhase[1]*Quadrature)   + .8*Im[1];
	print(d," ",o," ",h," ",l," ",c," ",value1," ",inPhase," ",Quadrature," ",Re," ",Im);
	If Re <> 0 then DeltaPhase = ArcTangent(Im/Re);

	{Sum DeltaPhases to reach 360 degrees.  The sum is the instantaneous period.}
	InstPeriod = 0;
	Value4 = 0;
	For count = 0 to 50 begin
		Value4 = Value4 + DeltaPhase[count];
		If Value4 > 360 and InstPeriod = 0 then begin
			InstPeriod = count;

	{Resolve Instantaneous Period errors and smooth}
	If InstPeriod = 0 then InstPeriod = InstPeriod[1];
	Period = .25*InstPeriod + .75*Period[1];

	Plot1(Period, "DC");
EasyLanguage Code For Calculating Dominant Cycle

In my Python based back tester an indicator of this type is best programmed by using a class.  A class is really a simple construct, especially in Python, once you familiarize yourself with the syntax.   This indicator requires you to refer to historical values to calculate the next value in the equation:  Value1[4], inPhase[1], re[2], etc.,.  In EasyLanguage these values are readily accessible as every variable is defined as a BarArray – the complete history of a variable is accessible by using indexing.  In my PSB I used lists to store values for those variables most often used such as Open, High, Low, Close.  When you need to store the values of let’s say the last five bars its best to just create a list on the fly or build them into a class structure.  A Class stores data and data structures and includes the methods (functions) that the data will be pumped into.  The follow code describes the class in two sections:  1) data declaration and instantiation and 2) the function to calculate the Dominant Cycle.  First off I create the variables that will hold the constant values: imult and qmult.  By using the word self I make these variables class members and can access them using “.” notation.  I will show you later what this means.  I also make the rest of the variables class members, but this time I make them lists and instantiate the first five values to zero.  I use list comprehension to create the lists and zero out the first five elements – all in one line of code.  This is really just a neat short cut, but can be used for much more powerful applications.  Once you create a dominantCycleClass object the object is constructed and all of the data is connected to this particular object.  You can create many dominantCycleClass objects and each one would maintain its own data.  Remember a class is just a template that is used to create an object.

class dominantCycleClass(object):
    def __init__(self):
        self.imult = 0.635
        self.qmult = 0.338
        self.value1 = [0 for i in range(5)]
        self.inPhase = [0 for i in range(5)]
        self.quadrature = [0 for i in range(5)] = [0 for i in range(5)] = [0 for i in range(5)]
        self.deltaPhase = [0 for i in range(5)]
        self.instPeriod = [0 for i in range(5)]
        self.period = [0 for i in range(5)]
Data Portion of Class


The second part of the class template contains the method or function for calculating the Dominant Cycle.  Notice how I index into the lists to extract prior values.  You will also see the word self. preceding the variable names used in the calculations Initially I felt like this redundancy hurt the readability of the code and in this case it might.  But by using self. I know I am dealing with a class member.  This is an example of the ” . ” notation I referred to earlier.  Basically this ties the variable to the class.

def calcDomCycle(self,dates,hPrices,lPrices,cPrices,curBar,offset):
        tempVal1 = (hPrices[curBar - offset] + lPrices[curBar-offset])/2
        tempVal2 = (hPrices[curBar - offset - 7] + lPrices[curBar-offset - 7])/2
        self.value1.append(tempVal1 - tempVal2)
        self.inPhase.append(1.25*(self.value1[-5] - self.imult*self.value1[-3]) + self.imult*self.inPhase[-3])        
        self.quadrature.append(self.value1[-3] - self.qmult*self.value1[-1] + self.qmult*self.quadrature[-2])*(self.inPhase[-1]*self.inPhase[-2]+self.quadrature[-1]*self.quadrature[-2])+ 0.8*[-1])*(self.inPhase[-1]*self.quadrature[-2] - self.inPhase[-2]*self.quadrature[-1]) +.8*[-1])
        if[-1] != 0.0: self.deltaPhase.append(degrees(atan([-1]/[-1])))
        if len(self.deltaPhase) > 51:
            value4 = 0
            for count in range(1,51):
                value4 += self.deltaPhase[-count]
                if value4 > 360 and self.instPeriod[-1] == 0:
            if self.instPeriod[-1] == 0: self.instPeriod.append(self.instPeriod[-1])
Dominant Cycle Method

Okay we now have the class template to calculate the Dominant Cycle but how do we us it?

#Instantiate Indicator Classes if you need them
#    rsiStudy = rsiClass()
#    stochStudy = stochClass()
    domCycle = dominantCycleClass()
#Call the dominantCycleClass method using " . " notation.
	tempVal1 = domCycle.calcDomCycle(myDate,myHigh,myLow,myClose,i,0)
#Notice how I can access class members by using " . " notation as well!
	tempVal2 = domCycle.imult
Dominant Cycle Object Creation

Here I assign domCycle the object created by calling the dominantCycleClass constructor.  TempVal1 is assigned the Dominant Cycle when the function or method is called using the objects name (domCycle) and the now familiar ” . ” notation.  See how you can also access the imult variable using the same notation.

Here is the code in its entirety.  I put this in the indicator module of the PSB.

class dominantCycleClass(object):
    def __init__(self):
        self.imult = 0.635
        self.qmult = 0.338
        self.value1 = [0 for i in range(5)]
        self.inPhase = [0 for i in range(5)]
        self.quadrature = [0 for i in range(5)] = [0 for i in range(5)] = [0 for i in range(5)]
        self.deltaPhase = [0 for i in range(5)]
        self.instPeriod = [0 for i in range(5)]
        self.period = [0 for i in range(5)]

    def calcDomCycle(self,dates,hPrices,lPrices,cPrices,curBar,offset):
        tempVal1 = (hPrices[curBar - offset] + lPrices[curBar-offset])/2
        tempVal2 = (hPrices[curBar - offset - 7] + lPrices[curBar-offset - 7])/2
        self.value1.append(tempVal1 - tempVal2)
        self.inPhase.append(1.25*(self.value1[-5] - self.imult*self.value1[-3]) + self.imult*self.inPhase[-3])        
        self.quadrature.append(self.value1[-3] - self.qmult*self.value1[-1] + self.qmult*self.quadrature[-2])*(self.inPhase[-1]*self.inPhase[-2]+self.quadrature[-1]*self.quadrature[-2])+ 0.8*[-1])*(self.inPhase[-1]*self.quadrature[-2] - self.inPhase[-2]*self.quadrature[-1]) +.8*[-1])
        if[-1] != 0.0: self.deltaPhase.append(degrees(atan([-1]/[-1])))
        if len(self.deltaPhase) > 51:
            value4 = 0
            for count in range(1,51):
                value4 += self.deltaPhase[-count]
                if value4 > 360 and self.instPeriod[-1] == 0:
            if self.instPeriod[-1] == 0: self.instPeriod.append(self.instPeriod[-1])
Dominant Cycle Class - Python