[R] extract all numbers from a string

Duncan Mackay mackay at northnet.com.au
Sun Jun 16 07:49:42 CEST 2013


Nick

try

as.numeric(
  strsplit(gsub("[[:alpha:][:punct:][:space:]]{2,}",",",tmpstr),",")[[1]][-1]
)

see ?regexpr for information

HTH

Duncan


Duncan Mackay
Department of Agronomy and Soil Science
University of New England
Armidale NSW 2351
Email: home: mackay at northnet.com.au



At 15:06 16/06/2013, you wrote:
>Hi all,
>
>I have been beating my head against this problem for a bit, but I 
>can't figure it out.
>
>I have a series of strings of variable length, and each will have 
>one or more numbers, of varying format.  E.g., I might have:
>
>
>tmpstr = "The first number is: 32.  Another one is: 32.1. Here's a 
>number in scientific format, 0.3523e10, and another, 0.3523e-10, and 
>a negative, -313.1"
>
>How could I get R to just give me a list of numerics containing the 
>numbers therein?
>
>Thanks very much to the regexp wizards!
>
>Cheers,
>Nick
>
>
>
>--
>====================================================
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>
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>
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