此为 Mathematica 8 文档,内容基于更早版本的 Wolfram 语言
查看最新文档(版本11.1)

Text (.txt)

Plain text file.
Universal format for storage and exchange of textual information.
Represents text as a sequence of characters and line separators.
Stores characters as ASCII, 8-bit Western character codes, or Unicode.
  • Import and Export support a variety of Western character encodings and the Unicode standard.
  • UTF (Unicode Transformation Format) and UCS (Universal Character Set) mapping methods are supported.
  • Mathematica can display a wide range of character sets, including Western and Asian scripts, mathematical symbols, and other special characters.
  • Import imports a text file as a string.
  • Export exports any expression to a text file.
  • Import["file.txt"] returns a string.
  • Export["file.txt", expr] creates a text file from the OutputForm representation of expr.
  • Import imports the specified element from a text file.
  • Import imports multiple elements.
  • The import format can be specified with Import["file", "Text"] or Import.
  • Export creates a text file by treating expr as specifying element elem.
  • Export treats each as specifying the corresponding .
  • Export exports expr with the specified option elements taken to have the specified values.
  • Export uses rules to specify the elements to be exported.
  • See the reference pages for full general information on Import and Export.
  • Save Selection As exports the selected part of a notebook as a plain text file.
"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"tabular representation of the text
"Lines"lines, given as a list of strings
"Plaintext"text file represented as a single Mathematica string
"String"raw byte string
"Words"words separated by spaces, given as a list of strings
  • Import["file.txt"] reads a text file, taking the character encoding to be by default.
  • Import attempts to read any text file as TSV, CSV, or Table, returning an array of strings and numbers.
  • Import["file", {"Text", "String"}] or Import["file.txt", "String"] imports a raw sequence of bytes and returns them as a Mathematica character string.
  • Specifying and selecting subelements of text files:
"Lines",nthe n^(th) line of the file
"Words",nthe n^(th) word in the file
  • When importing from a text file, Import automatically replaces any character sequence commonly used as a line separator with "".
  • Mathematica typically uses character code 10 () as a line separator in the internal representation of text.
  • Export uses the line separator convention of the computer system on which Mathematica is being run.
CharacterEncoding"UTF8"raw character encoding used in the file
"AdobeStandard"Adobe standard PostScript font encoding
"ASCII"full ASCII, with control characters
"EUC"extended Unix code for Japanese
"ISOLatin1"ISO 8859-1 standard
"ISOLatin2"ISO 8859-2 standard
"ISOLatin3"ISO 8859-3 standard
"ISOLatin4"ISO 8859-4 standard
"ISOLatinCyrillic"ISO 8859-5 standard
"MacintoshRoman"Macintosh roman font encoding
"PrintableASCII"printable ASCII
"ShiftJIS"Shift-JIS encoding of JIS X 0208-1990 and extensions
"Symbol"symbol font encoding
"Unicode"raw 2-byte Unicode values
"UTF8"variable-width 1-byte Unicode format
"WindowsANSI"Windows standard font encoding
  • Mathematica internally stores characters as Unicode values.
Import a text file and return the first few characters:
Import the first line from this file:
Import three lines:
Import this file using the element:
Any plain text file can be imported as text:
Export an arbitrary expression to text:
Import a text file and return the first few characters:
In[1]:=
Click for copyable input
Out[1]=
Import the first line from this file:
In[2]:=
Click for copyable input
Out[2]=
Import three lines:
In[3]:=
Click for copyable input
Out[3]=
Import this file using the element:
In[4]:=
Click for copyable input
Out[4]=
 
Any plain text file can be imported as text:
In[1]:=
Click for copyable input
Out[1]=
 
Export an arbitrary expression to text:
In[1]:=
Click for copyable input
Out[1]=