Uniform sequence of signed 64-bit integers.
Binary data format.
  • Import can read any file as a sequence of signed 64-bit integers.
  • Export writes a list of integers in the range to a binary file.

Import and ExportImport and Export

  • Import["file", "Integer64"] imports an arbitrary file as a sequence of signed 64-bit integers, returning a packed array of integers in the range .
  • Export["file", list, "Integer64"] exports a list of integers in the range to a sequence of binary 64-bit integers.
  • Import["file", {"Integer64", elem}] or Import["file", elem ] imports the specified element from file.
  • Import["file", {"Integer64", {elem1, elem2, ...}}] imports multiple elements.
  • See the reference pages for full general information on Import and Export.
  • ImportString and ExportString support the Integer64 format.


  • General Import elements:
  • "Elements" elements and options available in this file
    "Rules"full rules for each element and option
    "Options"rules for options, properties, and settings
  • Data representation element:
  • "Data"list of integers in the range
  • By default, Import and Export use the element.
  • Import["file", {"Integer64", n}] gives the n^(th) 64-bit integer.
  • Trailing bytes are ignored if the size of the imported file is not a multiple of the data size.


  • General option:
  • ByteOrdering-1what byte ordering to use
  • Import option:
  • "HeaderBytes"0how many bytes to skip at the beginning of the file

ExamplesExamplesopen allclose all

Basic Examples (1)Basic Examples (1)

Convert a list of integers to a string representing a sequence of binary 64-bit integers:

Click for copyable input

Verify that the correct number of bytes was written:

Click for copyable input

Convert the binary data back to an expression:

Click for copyable input

Import the same data, assuming it represents an array of unsigned integers:

Click for copyable input
New in 5.1 | Last modified in 6
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