Thanks for your suggestions. Bert, in your response you raised my awareness
to "regular expressions". Are regular expressions the same across various
languages? Consider the following line of text:
txt_line<-" PERCENT DISCREPANCY = 0.01 PERCENT DISCREPANCY =
-0.05"
It seems python uses the following line of code to extract the two values in
"txt_line" and store them in a variable called "v":
v = re.findall("[+-]? *(?:\d+(?:\.\d*)|\.\d+)(?:[eE][+-]?\d+)?", line)
#v[0] 0.01
#v[1] -0.05
I tried something similar in R (but it didn't work) by using the same
regular expression, but got an error:
edm<-grep("[+-]? *(?:\d+(?:\.\d*)|\.\d+)(?:[eE][+-]?\d+)?",txt_line)
#Error: '\d' is an unrecognized escape in character string starting "[+-]?
*(?:\d"
I'm not even sure which function in R most efficiently extracts the values
from "txt_line". Basically, I want to peel out the values and think I can
use the decimal point to construct the regular expression, but don't know
where to go from here?
--
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