[R] String Matching

Kevin Kowitski k.kowitski at icloud.com
Wed Aug 12 17:51:12 CEST 2015


Hey everyone, 

  I have been having an issue trying to find a specific string of text in a log of system messages.  I have tried to use pmatch, match, and some regular expressions but all to no avail.  

I have a matrix / data.frame (either one, the file outputs a tens of thousands of rows with a single column) of strings in the following format with different items after INFO:
 "09:11:57.259 - Assay File Processing Thread - INFO - SolenoidCycleMessage: Addr = 0x03 "

as an example I would like to match "SolenoidCycleMessage"
searchString<-"SolenoidCycleMessage"
matchString<-"09:11:57.259 - Assay File Processing Thread - INFO - SolenoidCycleMessage: Addr = 0x03"

> pmatch(searchString, matchString)
[1] NA

> match(searchString, matchString)
[1] NA
> match(matchString, searchString)
[1] NA
> grep(searchString, matchString, ignore.case=FALSE)
[1] 1
> df<-as.data.frame(c(matchString, string1, string2))
> df
                                                         c(matchString, string1, string2)
1 09:11:57.259 - Assay File Processing Thread - INFO - SolenoidCycleMessage: Addr = 0x03 
2                                                                      23:12:43.22 - Test
3                                                                                    test
> grep(searchString, df, ignore.case=FALSE)
integer(0)

> grep(searchString, c(matchString, string1, string2), ignore.case=FALSE)
[1] 1

Doe anyone have some input that could help?

Thanks, 
Kevin


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