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What it is

This tool integrates with Data Manager, allowing to perform certain operations on entire DataSets which would otherwise take certain effort:

  • Truncate last or first N bars (or N days of intraday data)
  • Wipe the entire DataSet data (to help mass reload)
  • Remove inactive (dead) symbols
  • Remove selected symbols
  • Change symbol
  • Check data for validity

Compatibility

Supported are static data providers that rely on Wealth-Lab to maintain their data in the local storage of .WL files. Only their DataSets will appear in the DataSets tree on the left and allow themselves to be processed.

  • Compatible: BBFree, CBOE, Fidelity, Finam, Forexite, Google, IQFeed, Market Sentiment, MSN, QuoteMedia, PiTrading, Random, Stooq, TradingBlox, Yahoo.
  • Incompatible: ASCII, Bloomberg Static, COTCollector, Database, Excel, Metastock, MetaTrader, MTiQs, Taipan, Telecharts, Watchlist, Zerich and other.

Quotes pane

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From this handy list you can take a quick peek at the market dynamics of the selected DataSet. The pane displays a table with the DateTime + OHLCV data for all symbols of the highlighted DataSet. For convenience, the table includes absolute and percentage change from the previous bar for each instrument. The data is displayed with respect to the number of default decimal places specified in Wealth-Lab's Preferences dialog.

By default, the table is sorted in descending order on the Bars.Count column to instantly show symbols with zero bars. It's possible to sort it in either ascending or descending order by repeatedly clicking on any column.

Below the Quotes pane, there are three tabs which group the actions you can perform on DataSets using the Data Tool:

  • Data truncation
  • Inactive symbols removal
  • Data checker

Datasource Truncation

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The following data truncation options apply to all symbols of highlighted DataSet:

  • The "Truncate" button makes possible to selectively remove a group of bars for all symbols of the selected DataSet. When "After" is selected in the suitable dropdown box, clicking "Truncate" deletes the last N bars of data. Selecting "Before" will remove the penultimate N bars. Activating the checkbox near the Date field sets the start date to truncate the data before or after. For intraday data it's also possible to delete last (or previous) N days by toggling the radio button (for non-intraday scales, last N bars will be removed). Requesting to delete more bars than a symbol has is equivalent to wiping out its entire historical data.
  • "Remove all data" is helpful if you want to reload the historical data of an entire DataSet but are reluctant to perform "Reload All History" manually. We know how tedious it could be when many symbols are involved. Click this button to nullify the accumulated data in highlighted DataSet, and then use Data Manager's "Update" button as you would do normally - the entire DataSet will be reloaded from scratch.

Dead symbol removal

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To clear highlighted DataSet from dead (inactive) symbols with 0 (zero) bars, click "Remove inactive". To additionally remove any symbols that stopped trading before some date, pick a date and enable the checkbox before clicking on "Remove inactive".

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Note: Before making changes, close all Strategy windows using the DataSet you're removing inactive symbols from.

Data validity checker

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To quickly verify a DataSet's integrity, click "Check data integrity" from the "Data checker" tab. The following errors are detected in historical data:

  • Erronenous bars (Close < Low, Open < Low, Open > High, Close > High, Low < 0, and Volume < 0)
  • Zero bars (OHLC = 0)
  • Duplicate dates
  • Out of sequence dates
  • Gap of N days that are not weekends or holidays
  • Data spikes (when close-to-close change exceeds a specified percentage e.g. +/- 20%). To avoid false positives, this option should be turned off on Yahoo! DataSets with split/dividend adjustment applied.
  • Weekend bars
  • No trading (volume = 0)

Due to the fact that some conditions like weekend bars are perfectly correct in some international markets, some options can be turned on or off.

Right click menu

Context menu features

Context menu features


The right click menu serves two purposes:

  • Change symbol: renames a single highlighted symbol. Simply type in the new symbol name and hit "Enter". Both the symbol name and its data file will be renamed. Helpful when symbol name changes for whatever reason.
  • Remove highlighted symbols from the current DataSet without affecting their data.

Limitations

  • By design, Data Tool works with raw data. Consequently, it's not possible to precisely determine market holidays when detecting for "Gap of N Days" errors, and "Spike Detection" will not work for Yahoo! DataSets with split/dividend adjustment applied.

  • A symbol has to have at least 2 bars of data to be visible in the Data Tool - required to calculate Change and Change %.

Important Disclaimer: The information provided by Wealth-Lab is strictly for informational purposes and is not to be construed as advice or solicitation to buy or sell any security.  The owner of Wealth-Lab.com assumes no liability resulting from the use of the material contained herein for investment purposes. By using this web site, you agree to the terms of this disclaimer and our Terms of Use.

Used under license from FMR Corp. Copyright 2008 FMR Corp. All rights reserved.


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