This is documentation for Mathematica 6, which was
based on an earlier version of the Wolfram Language.
View current documentation (Version 11.2)
Mathematica Import/Export Format


Uniform sequence of IEEE double-precision numbers.
Binary data format.
  • Import can read arbitrary binary data as a sequence of double-precision numbers.
  • Export can convert a list of arbitrary integers or reals to binary double-precision numbers.
  • Import["file", "Real64"] imports any file as 64-bit IEEE double-precision numbers, returning a packed array of real numbers.
  • Export["file", list, "Real64"] exports a list of real numbers to file.
  • Import["file", {"Real64", elem}] or Import["file", elem ] imports the specified element from file.
  • Import["file", {"Real64", {elem1, elem2, ...}}] imports multiple elements.
  • See the reference pages for full general information on Import and Export.
"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 real numbers
  • Import["file", {"Real64", n}] reads the n^(th) double-precision number from file.
  • 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
"HeaderBytes"0how many bytes to skip at the beginning of the file