Ray S. Ray S. - 5 months ago 87
R Question

Regex to extract double quotes and string in quotes R

I have a data frame with a column of "text." Each row of this column is filled with text from media articles.

I am trying to extract a string that occurs like this: "term" (including the double quotes around the term). I tried the following regular expression to capture instances where a word is sandwiched between two double quotes:

stri_extract_all_regex(df$text, '"(.+?)"')

This seems to capture some instances of what I am looking for, but in other cases - where I know the criteria are met - it does not. It also captures what seem to be just quotes of longer text (and not other instances of quoted text). Here are the results of using the above:

[1] "\"play a constructive and positive role\""
[2] "\"active and hectic reception\""
[3] "\"[term]\""

I would like to have only exactly "term" as the output (including the double quotes). I am trying to find instances when the term is used alone in quotes.

Example in R:
test <- c(df$text[12], df$text[18])
res <- stri_extract_all_regex(test, '"\\S+"')
[1] "\"Rohingya\"" "\"Bengali\"" NA

[1] "Former UN general secretary Kofi Annan will advise Myanmar's government on resolving conflicts in Rakhine State, the office of the state counsellor announced today.Former UN Secretary General Kofi Annan speaks at the opening of the Consciouness Summit on climate change in Paris, France on July 21, 2015. Photo: EPARakhine State, one of the poorest in the Union, was wracked by sectarian violence in 2012 that forced more than 100,000 – mostly Muslims who ethnically identify as Rohingya – into squalid displacement camps where they face severe restrictions on movement as well as access to health care, education, and other other basic services.Addressing the ongoing crises has posed one of the most troubling challenges to Daw Aung San Suu Kyi's National League for Democracy-led government.Earlier today, the government announced the formation of an advisory panel that will be chaired by former UN chief, and focus on \"finding lasting solutions to the complex and delicate issues in the Rakhine State\".The board will submit recommendations to the government on \"conflict prevention, humanitarian assistance, rights and reconciliation, institution-building and promotion of development of Rakhine State,\" a statement from the state counsellor's office said.The statement did not use the word \"Rohingya\". Daw Aung San Suu Kyi has come under fire both at home and from international rights groups for failing prioritise to address the group's plight and seeking to placate hardline Buddhist nationalists by avoiding the politically-charged term. The government has already requested that the US Embassy and other diplomatic groups avoid the term Rohingya, and in June, she proposed \"Muslim community of Rakhine State\".The proposed neutral terminology, which the state counsellor ordered government officials to adopt, sparked mass protests in Rakhine State and in Yangon by hardline nationalists, who insist on use of the term \"Bengali\" that was also preferred by the previous government's to suggest the group's origins in neighbouring Bangladesh.In July UN special rapporteur for human rights Yanghee Lee urged the government to make ending \"institutionalised discrimination\" against the Rohingya and other Muslims in Rakhine an urgent priority.Myanmar also announced this week that current UN Secretary General Ban Ki-moon will attend the highly-anticipated 21st Century Panglong conference at the end of the month.The five-day talks, aimed at ending a host of complicated border ethnic conflicts that have lasted for decades, will begin on August 31."

[2] "Thousands of Kaman Muslims from the Rakhine State capital Sittwe obtained identity cards this week, some two years after they applied for the documents.“Now the problem is solved. The Kaman got national ID cards. We had proposed to the government and immigration office to work on the process of giving ID cards to Kaman,” said U Tin Hlaing Win, general secretary of the Kaman National Development Party (KNDP).The Kaman, as one of 135 officially recognised ethnic groups in Myanmar entitled to full citizenship, had struggled to get authorities to grant them the IDs due to the complex ethnic demographics and fraught identity politics of Rakhine State.Complicating the process for the Kaman applicants has been the population of more than 1 million Muslims in Rakhine State who self-identify as Rohingya, most of whom are stateless. “Citizenship scrutiny” programs to issue some form of identification to the minority group by the previous and current governments have been met with resistance by Rakhine nationalists.The shared Muslim faith of the Kaman and Rohingya became just one aspect of a contentious debate over terminology earlier this year, when State Counsellor Daw Aung San Suu Kyi put forward the phrase “the Muslim community in Rakhine State” to refer to self-identifying Rohingya in an attempt to chart a middle course on the issue of lexicon. “Rohingya” stirs passions among Buddhist nationalists, who insist that they be called “Bengalis” to imply that they are illegal immigrants from neighbouring Bangladesh, despite many tracing familial lineage in Rakhine State back generations.Some Kaman have since viewed the state counsellor’s edict warily, concerned that the Kaman identity might be conflated with that of the Rohingya – who are not entitled to citizenship – and could jeopardise Kaman prospects for ID cards and full rights under the law.Violence in 2012 between Buddhists and Muslims in Rakhine State affected Rakhine Buddhists, Kaman and Rohingya, but the latter suffered the brunt of casualties and displacement.U Tin Hlaing Win told The Myanmar Times last week that some of the Kaman Muslims displaced by the conflict in the island town of Rambre had also recently received national ID cards.“The Kaman are ethnics belonging to Myanmar,” said U Than Htun Aung, a senior immigration officer for Rakhine State. “Township immigration officers will examine [legitimate Kaman claims to citizenship] according to the process and they will ensure they get their rights.”Around 2000 Kaman applied for national ID cards in 2014, but only 38 people were issued the documents.The others were told they had not received IDs because of the purported existence of “fake Kaman”.More than 100,000 people are thought to hold government-issued national ID cards identifying them as Kaman, but KNDP research in 2013 estimated the actual ethnic Kaman population to be about 50,000.U Tin Hlaing Win said sorting out the “fake Kaman” issue was not solely the responsibility of Kaman people, adding that immigration officers through the years, and generations of ethnically mixed marriages and the offspring they produced, were also to blame for the confusion.“According to our research and knowledge tracing family trees, some Kaman identity-card holders were Rakhine plus Bengali or Rakhine plus Indian, not Kaman. It [identity problems] should be solved by three groups – we Kaman, the Rakhine and immigration authorities,” U Tin Hlaing Win told The Myanmar Times last week.What most seem to agree on is that “real Kaman” deserve the documentation they need to enjoy the full rights of citizenship.Ethnic Rakhine youth leader Ko Khine Lamin said, “The Rakhine objected to national ID cards for Kaman because of the controversy over fake Kaman. But there are real Kaman who have lived in Rakhine State since a long, long time ago. They should get their ethnic rights through careful examination by immigration officers.”Kaman politicians are not satisfied with their victory this week and are trying to meet with Rakhine State Chief Minister U Nyi Pu to raise other difficulties Kaman people face, such as transportation barriers. They also intend to ask the chief minister for rehabilitation programs for Kaman internally displaced people, as well as education and health support for the broader Kaman community."

The above code can only return terms in [1].

Answer Source

The "(.+?)" pattern matches ", then any char other than line break chars, as few as possible, up to the closest (leftmost) ". It means it can match whitespaces, too, and thus matches "play a constructive and positive role" and "active and hectic reception".

To match a streak of non-whitespace chars in-between double quotes, you need to use

stri_extract_all_regex(df$text, '"\\S+"')

The "\S+" pattern matches ", then 1 or more non-whitespace chars, and then a closing ".

See the regex demo.

If you only want to match word chars (letters, digits, _) in between double quotes, use


See another regex demo.

To match curly quotes, use '["“]\\S+["”]' regex:

> res <- stri_extract_all_regex(test, '["“]\\S+["”]')
> unlist(res)
[1] "\"Rohingya\""         "\"Bengali\""          "\u0093Rohingya\u0094"
[4] "\u0093Bengalis\u0094"

And if you need to "normalize" the double quotes, use

> gsub("[“”]", '"', unlist(res))
[1] "\"Rohingya\"" "\"Bengali\""  "\"Rohingya\"" "\"Bengalis\""