These functions convert strings between encodings.
They aim to replace R's iconv.
They are not only faster, but also much more portable - they
work in the same manner on all platforms.
stri_encode(str, from = NULL, to = NULL, to_raw = FALSE)stri_conv(str, from = NULL, to = NULL, to_raw = FALSE)
a character vector, a raw vector, or
a list of raw vectors to be converted
input encoding:
NULL or "" for the default encoding
or internal encoding marks' usage (see Details);
otherwise, a single string with encoding name,
see stri_enc_list
target encoding:
NULL or "" for default encoding
(see stri_enc_get),
or a single string with encoding name
a single logical value; indicates whether a list of raw vectors rather than a character vector should be returned
If to_raw is FALSE,
then a character vector with encoded strings (and appropriate
encoding marks) is returned.
Otherwise, a list of raw vectors is produced.
stri_conv is an alias for stri_encode.
Please refer to stri_enc_list for the list
of supported encodings and stringi-encoding
for a general discussion.
If str is a character vector
and from is either missing, "", or NULL,
then the declared encodings are used
(see stri_enc_mark) -- in such a case bytes-declared
strings are disallowed.
Otherwise, the internal encoding declarations are ignored and
a converter selected via from is used.
If str is a raw-type vector
or a list of raw vectors,
we assume that the input encoding is the current default encoding
as given by stri_enc_get.
For to_raw=FALSE, the output
strings have always marked encodings according to the target converter
used (as specified by to) and the current default Encoding
(ASCII, latin1, UTF-8, native,
or bytes in all other cases).
Note that some issues might occur if to indicates, e.g,
UTF-16 or UTF-32, as the output strings may have embedded NULs.
In such cases, please use to_raw=TRUE and consider
specifying a byte order marker (BOM) for portability reasons
(e.g., set UTF-16 or UTF-32 which automatically
adds the BOMs).
Note that stri_encode(as.raw(data), "encodingname")
is a clever substitute for rawToChar.
In the current version of stringi, if an incorrect code point is found on input, it is replaced by the default (for that target encoding) substitute character. Also, in such a case a warning is generated.
Conversion -- ICU User Guide, http://userguide.icu-project.org/conversion
Converters -- ICU User Guide, http://userguide.icu-project.org/conversion/converters (technical details)
Other encoding_conversion: stri_enc_fromutf32,
stri_enc_toascii,
stri_enc_tonative,
stri_enc_toutf32,
stri_enc_toutf8,
stringi-encoding