Directory

  • Import can read files from general file directories.
  • Import also recognizes formats that are represented as a bundle of related files and organized in a directory structure.
  • Background

      File system directory hierarchy.
      Can contain files and subdirectories.

    Import and Export

    • When importing from a directory that constitutes a supported multifile Import format, the converter for this format will be used.
    • Import["dir"] gives path specifications for all files in a general directory "dir" and its subdirectories.
    • Import["dir"] returns a list of pathnames as an expression of the form {"fn1","fn2", }.
    • Import["dir","fn"] imports "\"\!\(\*\nStyleBox[\"dir\", \"TI\"]\)\!\(\*\nStyleBox[\"/\", \"TI\"]\)\!\(\*\nStyleBox[\"fn\", \"TI\"]\)\!\(\*\nStyleBox[\"\\\"\", \"TI\"]\)".
    • Import["dir",elem] imports the specified element from a directory.
    • Import["dir",{elem,suba,subb,}] imports a subelement.
    • Import["dir",{{elem1,elem2,}}] imports multiple elements.
    • Because the Wolfram Language can determine whether a path specification refers to a directory, it is normally not necessary to specify "Directory" as a format in the second argument of Import.
    • Import["dir","Directory"] or Import["dir",{"Directory",elem,}] explicitly specifies "Directory" as the Import format.
    • See the reference pages for full general information on Import.

    Elements

    • 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
    • The following can be used to select or specify individual files in a directory:
    • "FileNames"list of full pathnames for all files
      "filename"a single file
      "filename","format" a single file, taken to be in the specified format
      "filename","format",elemelement elem from the specified file
    • Import by default uses the "FileNames" element for directories.
    • Import["dir","fn"] imports "dir/fn".
    • File names can include relative or absolute directory specifications and the abbreviated string patterns supported by StringMatchQ.
    • Import["dir","*"] imports an entire directory.
    • Import["dir","subdir/*.jpg"] imports all JPEG files from "dir/subdir".

    Examples

    Basic Examples  (1)

    Import and count the file names included in this installation of the Wolfram System:

    In[1]:=
    Click for copyable input
    Out[1]=

    Show the names of some example files included in the Wolfram System:

    In[2]:=
    Click for copyable input
    Out[2]=

    Import a file from a directory, specifying its name as an Import element:

    In[3]:=
    Click for copyable input
    Out[3]=

    See Also

    "BZIP2"  "GZIP"  "SDTS"  "TAR"  "ZIP"

    Introduced in 2007
    (6.0)