TDT format files

The Tab-Delimited Text (TDT) file format is a general purpose file format that is used extensively in eArray to both upload and download tables of data. TDT files are plain text files that can be created and read by word processing and spreadsheet programs.

In a TDT file, items within a row of the data table are separated by <TAB> characters, and each row ends with a <RETURN> character. Blank or missing data items still require a <TAB> character. In this way, TDT files can specify the structure and content of a data table with any number of rows and columns.

For example, if you have a data table that looks like this:

blue	2334	Lincoln
red		Jefferson
green	12
	38	Washington

Then the TDT file would look like this:

blue <TAB> 2334 <TAB> Lincoln <RETURN>
red <TAB> <TAB> Jefferson <RETURN>
green <TAB> 12 <TAB> <RETURN>
<TAB> 38 <TAB> Washington <RETURN>

- Note: If you create this TDT file with a word processor, <TAB> indicates that you press the Tab key, and <RETURN> indicates that you press the Return or Enter key on your keyboard.

TDT is not the native file format for most word processing and spreadsheet programs. When you save the file, use the Save As command, and save the file as a plain text file. In spreadsheet programs, you may need to specify the type of text file as tab-delimited. Similarly, when you open a downloaded TDT file in a spreadsheet program, you may need to specify that the file is tab-delimited.

In a TDT file from eArray, the first line of the file is usually a row of column headers. However, when you upload a TDT file, eArray does not interpret column header data, and may treat column headers in your file as actual data, unless you specify otherwise during the upload process.

In the special case of a TDT file that represents a table with a single column of data, the "tab-delimited" text file actually contains no <TAB> characters. The data items are actually separated by <RETURN> characters.

For uploaded probe files, eArray supports two general types of TDT files:

Complete — Seven columns:

ProbeID

Sequence

TargetID

Accessions

GeneSymbols

Description

ChromosomalLocation

Minimal — Two columns:

ProbeID

Sequence

For descriptions of these columns see Probe file formats and requirements for uploading. The columns in uploaded bait files for the SureSelect Target Enrichment and SureSelect RNA Enrichment application types are different — see Upload baits.