Wolfram Language & System 11.0 (2016)|Legacy Documentation

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StringExtract

StringExtract["string",n]
extracts the n^(th) block of characters in string, where blocks of characters are defined as delimited by whitespace.

StringExtract["string",{pos1,pos2,}]
extracts blocks at several positions in string.

StringExtract["string",seppos]
takes blocks to be delimited by separators that match sep.

StringExtract["string",pos1,pos2,]
extracts blocks at positions posi, delimiting with whitespace for the lowest level, newlines for the next level, and a successively increasing number of newlines thereafter.

StringExtract["string",sep1pos1,sep2pos2,]
gives a nested list of blocks, with the sepi used as separators for successive levels.

DetailsDetails

  • The position specifications for blocks can have any of the following forms:
  • nn^(th) block
    -nn^(th) block counting from the end
    {n1,n2,}collection of blocks
    n1;;n2n1^(th) through n2^(th) block
    Allall blocks
  • The separator sep can be a literal string or a string pattern.

ExamplesExamplesopen allclose all

Basic Examples  (4)Basic Examples  (4)

Take the second whitespace-delimited element in a string:

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Take a list of elements:

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Take the first two whitespace-delimited elements:

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Take the last whitespace-delimited element:

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Take the second colon-delimited element in a string:

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Give all the colon-delimited elements:

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Take the first whitespace-delimited word from each line:

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Take the first word from the 3rd line:

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Take every word from the third line:

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Elements not present in a group yield Missing[]:

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Extract the first column from a string in CSV (comma-separated values) format:

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Extract all columns:

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Extract only the first row:

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Introduced in 2015
(10.1)