Bert Gunter
2025-Sep-14 18:05 UTC
[R] trouble with exporting a data.frame with " (quotation mark) in some columns into a tab delimited file, then importing the file
See ?write.table documentation for "qmethod", which needs to be set to "double" to write the data correctly for csv. This is most easily done by using read.csv and write.csv, for which this is the default. Ergo, the following : (using your example)> write.csv(db, file = "test", row.names = FALSE)## Note: Set row.names = FALSE so an extra column of numeric row names won't be added.> db2 <- read.csv("test") ## read it back in > identical(db2, db)[1] TRUE Apologies if I have misunderstood and this does not solve your problem. Cheers, Bert On Sun, Sep 14, 2025 at 10:46?AM Patrick Giraudoux <patrick.giraudoux at univ-fcomte.fr> wrote:> > Dear listers, previous plain text was still more messy, > > Here a trial hopefully better... > > I encountered an issue with a CSV file that was imported correctly but > could not be re-imported correctly after being written with R. This is > probably because geographical coordinates were imported as character in > degrees, minutes and seconds (DMS), which includes " (quotation mark) > for the seconds. > > Below a reproducible example: > > db <- structure(list(lon = c(6.228561, 6.22532, 6.2260499999999999, > 6.2267789999999996, 6.2224659999999998, 6.2209430000000001), latdms > c("47?12'28.36\"N", "47?12'33.46\"N", "47?12'28.37\"N", > "47?12'27.48\"N", "47?12'31.31\"N", "47?12'33.15\"N"), londms > c("6?13'42.82\"E", "6?13'31.15\"E", "6?13'33.78\"E", "6?13'36.40\"E", > "6?13'20.88\"E", "6?13'15.39\"E"), fusutmn = c(32L, 32L, 32L, 32L, 32L, > 32L)), row.names = c(NA, 6L), class = "data.frame") > > > db > > write.table(db, file = "db.txt", row.names = FALSE, quote = FALSE, sep > "\t") > > db_import<-read.delim("db.txt") > > > db_import > > > As you can see it, latdms and londms are now collapsed and all the > columns on the right have shifted to the left. I get the same issue > with ; as a separator. > > > I could not find a workaround... > > Any hint appreciated, > > Patrick > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide https://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.
Ben Bolker
2025-Sep-14 19:01 UTC
[R] trouble with exporting a data.frame with " (quotation mark) in some columns into a tab delimited file, then importing the file
Or set quote = TRUE (OP is using delim="\t" to export a tab-separated file ... On 9/14/25 14:05, Bert Gunter wrote:> See ?write.table documentation for "qmethod", which needs to be set > to "double" to write the data correctly for csv. This is most easily > done by using read.csv and write.csv, for which this is the default. > Ergo, the following : > > (using your example) > >> write.csv(db, file = "test", row.names = FALSE) > ## Note: Set row.names = FALSE so an extra column of numeric row names > won't be added. >> db2 <- read.csv("test") ## read it back in >> identical(db2, db) > [1] TRUE > > Apologies if I have misunderstood and this does not solve your problem. > > Cheers, > Bert > > > On Sun, Sep 14, 2025 at 10:46?AM Patrick Giraudoux > <patrick.giraudoux at univ-fcomte.fr> wrote: >> >> Dear listers, previous plain text was still more messy, >> >> Here a trial hopefully better... >> >> I encountered an issue with a CSV file that was imported correctly but >> could not be re-imported correctly after being written with R. This is >> probably because geographical coordinates were imported as character in >> degrees, minutes and seconds (DMS), which includes " (quotation mark) >> for the seconds. >> >> Below a reproducible example: >> >> db <- structure(list(lon = c(6.228561, 6.22532, 6.2260499999999999, >> 6.2267789999999996, 6.2224659999999998, 6.2209430000000001), latdms >> c("47?12'28.36\"N", "47?12'33.46\"N", "47?12'28.37\"N", >> "47?12'27.48\"N", "47?12'31.31\"N", "47?12'33.15\"N"), londms >> c("6?13'42.82\"E", "6?13'31.15\"E", "6?13'33.78\"E", "6?13'36.40\"E", >> "6?13'20.88\"E", "6?13'15.39\"E"), fusutmn = c(32L, 32L, 32L, 32L, 32L, >> 32L)), row.names = c(NA, 6L), class = "data.frame") >> >> > db >> >> write.table(db, file = "db.txt", row.names = FALSE, quote = FALSE, sep >> "\t") >> >> db_import<-read.delim("db.txt") >> >> > db_import >> >> >> As you can see it, latdms and londms are now collapsed and all the >> columns on the right have shifted to the left. I get the same issue >> with ; as a separator. >> >> >> I could not find a workaround... >> >> Any hint appreciated, >> >> Patrick >> >> ______________________________________________ >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide https://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code. > > ______________________________________________ > R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see > https://stat.ethz.ch/mailman/listinfo/r-help > PLEASE do read the posting guide https://www.R-project.org/posting-guide.html > and provide commented, minimal, self-contained, reproducible code.-- Dr. Benjamin Bolker Professor, Mathematics & Statistics and Biology, McMaster University Associate chair (graduate), Mathematics & Statistics Director, School of Computational Science and Engineering * E-mail is sent at my convenience; I don't expect replies outside of working hours.
Patrick Giraudoux
2025-Sep-14 19:28 UTC
[R] trouble with exporting a data.frame with " (quotation mark) in some columns into a tab delimited file, then importing the file
Fantastic Bert ! It works perfect. Now I will dig in a bit to understand how write.csv works... Thank you, Patrick Le 14/09/2025 ? 20:05, Bert Gunter a ?crit?:> See ?write.table documentation for "qmethod", which needs to be set > to "double" to write the data correctly for csv. This is most easily > done by using read.csv and write.csv, for which this is the default. > Ergo, the following : > > (using your example) > >> write.csv(db, file = "test", row.names = FALSE) > ## Note: Set row.names = FALSE so an extra column of numeric row names > won't be added. >> db2 <- read.csv("test") ## read it back in >> identical(db2, db) > [1] TRUE > > Apologies if I have misunderstood and this does not solve your problem. > > Cheers, > Bert > > > On Sun, Sep 14, 2025 at 10:46?AM Patrick Giraudoux > <patrick.giraudoux at univ-fcomte.fr> wrote: >> Dear listers, previous plain text was still more messy, >> >> Here a trial hopefully better... >> >> I encountered an issue with a CSV file that was imported correctly but >> could not be re-imported correctly after being written with R. This is >> probably because geographical coordinates were imported as character in >> degrees, minutes and seconds (DMS), which includes " (quotation mark) >> for the seconds. >> >> Below a reproducible example: >> >> db <- structure(list(lon = c(6.228561, 6.22532, 6.2260499999999999, >> 6.2267789999999996, 6.2224659999999998, 6.2209430000000001), latdms >> c("47?12'28.36\"N", "47?12'33.46\"N", "47?12'28.37\"N", >> "47?12'27.48\"N", "47?12'31.31\"N", "47?12'33.15\"N"), londms >> c("6?13'42.82\"E", "6?13'31.15\"E", "6?13'33.78\"E", "6?13'36.40\"E", >> "6?13'20.88\"E", "6?13'15.39\"E"), fusutmn = c(32L, 32L, 32L, 32L, 32L, >> 32L)), row.names = c(NA, 6L), class = "data.frame") >> >> > db >> >> write.table(db, file = "db.txt", row.names = FALSE, quote = FALSE, sep >> "\t") >> >> db_import<-read.delim("db.txt") >> >> > db_import >> >> >> As you can see it, latdms and londms are now collapsed and all the >> columns on the right have shifted to the left. I get the same issue >> with ; as a separator. >> >> >> I could not find a workaround... >> >> Any hint appreciated, >> >> Patrick >> >> ______________________________________________ >> R-help at r-project.org mailing list -- To UNSUBSCRIBE and more, see >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guidehttps://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible code.[[alternative HTML version deleted]]