UPDATED workflow as of 1/22/2020
I do a lot of back testing with PowerShell. This article demonstrates how to export historical data from thinkorswim to a csv file, and then convert that output file to something that is a truly valid csv file which can be imported by PowerShell or any other program.
Overview of export process
This requires a few steps, and once you have done this once, subsequent exports will come naturally.
() Add a strategy to a chart that simulates a trade on every bar (1 buy to open, 1 sell to close).
This strategy will put Symbol, Open, High, Low, Close, PreviousClose (SOHLCP) data in the Name of the buy order. We will ignore the sell orders.
() Use the Show Report context menu to save the trades to a csv file.
The output file has extra information in it and it not a truly valid csv file.
() Run a PowerShell script I created called Get-SOHLCP.ps1 which transforms the csv file into a proper object which can be saved, or used in further analysis.
Export the strategy report
Open this chart in thinkorswim, it has the strategy code in it.
From your main TOS window, use Setup | Open Shared Item and paste this link in:
https://tos.mx/1FmyWu4
Every bar will have a buy and close. Right click one of the signals and export from Show Report menu item.
The strategy takes parameters for start/end times in the EST time zone.
Code for the kg_EveryTickSOHLCP strategy
Code:
#
# kg_EveryTickSOHLCP
#
# Strategy to capture every bar OHLC and P, the previous close.
# Useful for exporting data from TOS into a CSV file for further processing.
#
# Author: Kory Gill, @korygill
#
declare upper;
declare once_per_bar;
input startTime = 820; #hint startTime: start time in EST 24-hour time
input endTime = 1600; #hint endTime: end time in EST 24-hour time
def adjStartTime = startTime;# - 1;
def adjEndTime = endTime;# - 1;
def agg = GetAggregationPeriod();
# we use a 1 bar offset to get orders to line up, so adjust for that here
def marketOpen = if agg >= AggregationPeriod.DAY then 1 else if SecondsTillTime(adjEndTime) >= 60 and SecondsFromTime(adjStartTime) >= -60 then 1 else 0;
AddOrder(OrderType.BUY_TO_OPEN,
marketOpen,
low,
1,
Color.White,
Color.White,
name="SOHLCP|"+GetSymbol()+"|"+open[-1]+"|"+high[-1]+"|"+low[-1]+"|"+close[-1]+"|"+close);
AddOrder(OrderType.SELL_TO_CLOSE, marketOpen, high, 1, Color.White, Color.White, name="SellClose");
Transform the thinkorswim csv file to data you can work with
Use this PowerShell script, Get-SOHLCP.ps1, to transform the exported file.
Save the code below as “Get-SOHLCP.ps1” and run similar to the steps shown below.
Code:
#
# Get-SOHLCP.ps1
#
# Script to convert a TOS ThinkOrSwim kg_EveryTickOHLCP strategy report csv file to an object and/or proper csv data file.
#
# Author: Kory Gill, @korygill
#
[CmdletBinding()]
param (
[string[]]
$File,
[switch]
$ExportAsObject
)
function Convert-CurrencyStringToDecimal ([string]$input)
{
((($input -replace '\$') -replace '[)]') -replace '\(', '-') -replace '[^-0-9.]'
}
$global:sohlcpData = New-Object System.Collections.Generic.List[PSCustomObject]
foreach ($f in $File)
{
if (-not (Test-Path $f))
{
throw "Cannot open file '$f'."
}
# read csv file
$content = Get-Content -Path $f
# find the lines that contain price information
$csvdata = $content | ? {$_ -match ";.*;"} | ConvertFrom-Csv -Delimiter ';'
# filter just the lines with (OHLC on them and make into CSV structure
$data = $csvData | ? {$_ -match "\(SOHLCP"}
foreach ($item in $data)
{
# capture the OHLC data
$null = $item.Strategy -match "\(SOHLCP\|(.*)\)"
$v = $Matches[1] -split '\|'
$symbol = $v[0]
$open = $v[1] | Convert-CurrencyStringToDecimal
$high = $v[2] | Convert-CurrencyStringToDecimal
$low = $v[3] | Convert-CurrencyStringToDecimal
$close = $v[4] | Convert-CurrencyStringToDecimal
$prevClose = $v[5] | Convert-CurrencyStringToDecimal
# add to our $sohlcpData array
$null = $sohlcpData.Add(
[PSCustomObject]@{
'Symbol' = $symbol
'DateTime' = ([datetime]::Parse($item.'Date/Time'))
'Open' = [decimal]$open
'High' = [decimal]$high
'Low' = [decimal]$low
'Close' = [decimal]$close
'PrevClose' = [decimal]$prevClose
}
)
}
}
if ($ExportAsObject)
{
# helpful message to show caller our output variable
Write-Output "Out Data $($sohlcpData.Count) items (exported as `$sohlcpData)"
}
else
{
# don't show any output, and just return the data to the pipeline
return $sohlcpData
}
From a PowerShell command window, run the script and pass your exported csv file as a parameter.
Examples:
$data = .\Get-OHLC.ps1 .\StrategyReports_ESXCME_81919.csv
$data = D:\tos-data\Get-OHLC.ps1 D:\tos-data\StrategyReports_ESXCME_81919.csv
The converted data is now an object:
$data | ft
Code:
Symbol DateTime Open High Low Close PrevClose
------ -------- ---- ---- --- ----- ---------
/ES:XCME 1/17/2020 12:00:00 AM 3316.75 3330.25 3316 3323.75 3317.25
/ES:XCME 1/21/2020 12:00:00 AM 3325 3329.75 3307.25 3320.25 3323.75
/ES:XCME 1/22/2020 12:00:00 AM 3321.25 3337.5 3315.25 3317.25 3320.25
or
$data | ft
Code:
Symbol DateTime Open High Low Close PrevClose
------ -------- ---- ---- --- ----- ---------
/ES:XCME 1/17/2020 6:30:00 AM 3325.25 3326 3323.75 3324.5 3325.5
/ES:XCME 1/17/2020 6:31:00 AM 3324.25 3324.5 3322.25 3322.25 3324.5
/ES:XCME 1/17/2020 6:32:00 AM 3322.25 3322.75 3320.75 3321.75 3322.25
/ES:XCME 1/17/2020 6:33:00 AM 3321.75 3322.5 3321 3322.25 3321.75
/ES:XCME 1/17/2020 6:34:00 AM 3322.25 3322.5 3321.5 3322 3322.25
/ES:XCME 1/17/2020 6:35:00 AM 3322.25 3323.5 3321.75 3323 3322
/ES:XCME 1/20/2020 6:30:00 AM 3321 3321.25 3320.5 3320.5 3320.75
/ES:XCME 1/20/2020 6:31:00 AM 3320.75 3320.75 3320.25 3320.5 3320.5
/ES:XCME 1/20/2020 6:32:00 AM 3320.5 3321.75 3320.5 3321.75 3320.5
/ES:XCME 1/20/2020 6:33:00 AM 3321.5 3321.75 3321 3321.25 3321.75
/ES:XCME 1/20/2020 6:34:00 AM 3321.25 3321.75 3321 3321.5 3321.25
/ES:XCME 1/20/2020 6:35:00 AM 3321.5 3321.75 3321.25 3321.75 3321.5
Save the $data object as a proper csv file:
$data | ConvertTo-Csv -NoTypeInformation | Out-File -FilePath d:\tos-data\ES-Data.csv
Start back testing!
Now that you have data, you can back test your strategies with code outside thinkorswim. Note, you can only export up to 30 days of 1-minute data. You can use OnDemand to load data beyond that, but for this amount of work, maybe getting data from a provider is a better route. Kibot,
http://www.kibot.com/, is a good source, and you can find others on the web. Lastly, if you only export the subset of data you need, you can save a lot of time running the strategy in thinkorswim.
Happy trading,
Kory Gill,
@korygill