[R] Counting enumerated items in each element of a character vector

[Boris Steipe]

I should add: there's a str_count() function in the stringr package.

library(stringr)
str_count(text1, "Example")
# [1] 5 5 5 5

I guess that would be the neater solution.

B.



> On Apr 25, 2017, at 8:23 PM, Boris Steipe <boris.steipe at utoronto.ca> wrote:
> 
> How about:
> 
> unlist(lapply(strsplit(text1, "Example"), function(x) { length(x) - 1 } ))
> 
> 
> Splitting your string on the five "Examples" in each gives six elements. length(x) - 1 is the number of
> matches. You can use any regex instead of "example" if you need to tweak what you are looking for.
> 
> 
> B.
> 
> 
> 
> 
>> On Apr 25, 2017, at 8:14 PM, Dan Abner <dan.abner99 at gmail.com> wrote:
>> 
>> Hi all,
>> 
>> I am looking for a streamlined way of counting the number of enumerated
>> items are each element of a character vector. For example:
>> 
>> 
>> text1<-c("This is an example.
>> List 1
>> 1) Example 1
>> 2) Example 2
>> 10) Example 10
>> List 2
>> 1) Example 1
>> 2) Example 2
>> These have been examples.","This is another example.
>> List 1
>> 1. Example 1
>> 2. Example 2
>> 10. Example 10
>> List 2
>> 1. Example 1
>> 2. Example 2
>> These have been examples.","This is a third example. List 1 1) Example 1.
>> 2) Example 2. 10) Example 10. List 2 1) Example 1. 2) Example 2. These have
>> been examples."
>> ,"This is a fourth example. List 1 1. Example 1. 2. Example 2. 10. Example
>> 10. List 2 Example 1. 2. Example 2. These have been examples.")
>> 
>> text1
>> 
>> ===
>> 
>> I would like the result to be c(5,5,5,5). Notice that sometimes there are
>> leading hard returns, other times not. Sometimes are there separate lists
>> and the same numbers are used in the enumerated items multiple times within
>> each character string. Sometimes the leading numbers for the enumerated
>> items exceed single digits. Notice that the delimiter may be ) or a period
>> (.). If the delimiter is a period and there are hard returns (example 2),
>> then I expect that will be easy enough to differentiate sentences ending
>> with a number from enumerated items. However, I imagine it would be much
>> more difficult to differentiate the two for example 4.
>> 
>> Any suggestions are appreciated.
>> 
>> Best,
>> 
>> Dan
>> 
>> 	[[alternative HTML version deleted]]
>> 
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> 
> ______________________________________________
> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see
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> and provide commented, minimal, self-contained, reproducible code.