This is documentation for Mathematica 9, which was
based on an earlier version of the Wolfram Language.
MATHEMATICA IMPORT/EXPORT FORMAT

# Table (.dat)

Generic tabular data.
Stores numerical and textual information, formatted as a table.
Supports user-defined field and record separators, field delimiters, currency tokens, and number formats.
Plain text format.
• Import and Export fully support the Table format and provide various data conversion and formatting options.
• Import automatically recognizes common number formats, including C and Fortran notations.
• Numbers without decimal points are imported as integers.

## Import and ExportImport and Export

• Import["file.dat"] imports a Table file, returning a list of lists.
• Export["file.dat", expr] exports a two-dimensional array or a Grid to a Table file.
• Import["file.dat"] returns a two-dimensional array of strings and numbers, representing the rows and columns stored in the file.
• Export["file.dat", array] formats array as rows and columns using the CForm of each element.
• Mathematica automatically transforms arbitrary expressions to a list of lists when exporting to the Table format.
• Import["file.dat", elem] imports the specified element from a Table file.
• Import["file.dat", {elem, suba, subb, ...}] imports a subelement.
• Import["file.dat", {{elem1, elem2, ...}}] imports multiple elements.
• The import format can be specified with Import["file", "Table"] or Import["file", {"Table", elem, ...}].
• Export["file.dat", expr, elem] creates a Table file by treating expr as specifying element elem.
• Export["file.dat", {expr1, expr2, ...}, {{elem1, elem2, ...}}] treats each as specifying the corresponding .
• Export["file.dat", expr, opt1->val1, ...] exports expr with the specified option elements taken to have the specified values.
• Export["file.dat", {elem1->expr1, elem2->expr2, ...}, "Rules"] uses rules to specify the elements to be exported.
• See the reference pages for full general information on Import and Export.
• ImportString and ExportString support the Table format.

## Notebook InterfaceNotebook Interface

• Save Selection As exports the selected part of a notebook as a Table file.

## ElementsElements

• General Import elements:
•  "Elements" list of elements and options available in this file "Rules" full list of rules for each element and option "Options" list of rules for options, properties, and settings
• Data representation elements:
•  "Data" two-dimensional array, representing the rows and columns "Grid" table data as a Grid object
• Import and Export use the element by default.

## OptionsOptions

• General Export options:
•  Alignment None how data is aligned within table columns CharacterEncoding "UTF8" raw character encoding used in the file
• Possible settings for Alignment are None, Left, Center, and Right.
• General Import option:
•  CharacterEncoding "ASCII" raw character encoding used in the file
• Import and Export option:
•  "TextDelimiters" Automatic string or list of strings used to delimit non-numeric fields
• By default, Export delimits text fields containing the field separator with double-quote characters.
• With an explicit setting of , Export always uses the specified string tokens to delimit text fields, effectively cycling through the list of delimiters.
• With , Export wraps text fields in angular brackets.
• Double-quote characters delimiting text fields are not imported by default.
• Import options:
•  "CurrencyTokens" {{"\$", "", "", ""}, {"c", "", "p", "F"}} currency units to be skipped when importing numerical values "DateStringFormat" None date format, given as a DateString specification "FieldSeparators" {" ","\t"} string tokens taken to separate columns "IgnoreEmptyLines" False whether to ignore empty lines "LineSeparators" {"\r\n","\n","\r"} string tokens taken to separate rows "Numeric" True whether to import data fields as numbers if possible "NumberPoint" "." decimal point string "NumberSigns" {"-","+"} strings to use for signs of negative and positive numbers "RepeatedSeparators" True whether to parse a sequence of field separators as a single separator "HeaderLines" 0 number of lines to skip at the beginning of the file
• Import converts table entries formatted as specified by the option to a DateList representation of the form .
• Empty lines and lines containing only whitespace characters are converted to an empty list by default. With set to True, Import will skip empty lines.
• With "Numeric"->False, numbers will be imported as strings in the form they appear in the file.
• With the default setting for , Import automatically recognizes all common conventions for the encoding of line-separator characters.
• Export options:
•  "FieldSeparators" "\t" string token used to separate columns "TableHeadings" None headings for table columns and rows
• can be set to the following values:
•  None no labels Automatic gives successive integer labels for columns and rows {"col1","col2",...} list of column labels {rhead,chead} specifies separate labels for the rows and columns
• Export encodes line separator characters using the convention of the computer system on which Mathematica is being run.

## ExamplesExamplesopen allclose all

### Basic Examples (5)Basic Examples (5)

Export an array of random numbers as a table:

 Out[1]=

Export a table formatted as a grid:

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Import the generated file:

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Use ExportString to create a formatted version of an array:

 Out[4]=

Import a tabular data file that uses vertical bars as field separators:

 Out[1]=

Import converts dates to a Mathematica DateList specification if the date format is specified:

 Out[1]=

Create a UTF-8 encoded text file that contains currency tokens:

 Out[1]=

When importing this file, currency tokens are automatically skipped:

 Out[2]=

Mathematica automatically converts expressions to a list of lists when exporting to the Table format:

 Out[1]=
 Out[2]=