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Mathematica Import/Export Format

MX (.mx)

Mathematica serialized package format.
Used for the distribution of Mathematica packages.
Stores arbitrary Mathematica expressions in a serialized format optimized for fast loading.
Binary file format.
MX files cannot be exchanged between different operating systems or versions of Mathematica.
Developed by Wolfram Research.
  • Mathematica MX files can be created with DumpSave and read with Get.
  • Import[""]reads in an MX file and returns an expression.
  • Export["", expr] serializes an arbitrary Mathematica expression and saves it as an MX file.
  • Import["", elem] imports the specified element from an MX file.
  • The import format can be specified with Import["file", "MX"] or Import["file", {"MX", elem, ...}].
  • Import[""] is equivalent to Get[""].
  • See the reference pages for full general information on Import and Export.
"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
"Expression"reads and evaluates all expressions, returning the last one
"HeldExpression"list of unevaluated expressions
  • Import by default uses the "Expression" element for Mathematica MX files.