[R] extract all numbers from a string

Nick Matzke matzke at berkeley.edu
Sun Jun 16 07:06:43 CEST 2013


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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====================================================
Nicholas J. Matzke
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