| Title: | Read and Write Standard 'C' Types from Files, Connections and Raw Vectors |
|---|---|
| Description: | Interacting with binary files can be difficult because R's types are a subset of what is generally supported by 'C'. This package provides a suite of functions for reading and writing binary data (with files, connections, and raw vectors) using 'C' type descriptions. These functions convert data between 'C' types and R types while checking for values outside the type limits, 'NA' values, etc. |
| Authors: | Mike Cheng [aut, cre, cph], Anne Fu [ctb] (Better UTF-8 support, <https://orcid.org/0000-0002-9025-6071>) |
| Maintainer: | Mike Cheng <[email protected]> |
| License: | MIT + file LICENSE |
| Version: | 0.1.1.9001 |
| Built: | 2024-11-13 23:20:36 UTC |
| Source: | https://github.com/coolbutuseless/ctypesio |
Permute an R array to a linear vector of data
aperm_array_to_vector(x, dst, flipy = FALSE)aperm_array_to_vector(x, dst, flipy = FALSE)
x |
array |
dst |
Specification of destination dimensions in the order of presentation in the source data. Character vector which contains 3 strings: 'planes', 'rows', 'cols'. The order of these strings determines the order of output in the linear data. Currently, "planes" must always be the final element. |
flipy |
flip the array vertically. Default: FALSE |
vector
Other data permutation functions:
aperm_vector_to_array(),
flip_endian()
# create a small RGBA array in R with each # plane of the array holding a different colour channel arr <- array(c(paste0('r', 1:6), paste0('g', 1:6), paste0('b', 1:6), paste0('a', 1:6)), c(2, 3, 4)) arr # A very common C ordering is packaged RGBA data in column major format # i.e. Iterate over: planes, then columns, then rows # i.e. # start at first element # (plane1, plane2, plane3, plane4) # go to next column # (plane1, plane2, plane3, plane4) # go to next column # ... # when last column is done # do to next row # Convert to packed RGBA in column-major format vec <- aperm_array_to_vector(arr, dst = c('planes', 'cols', 'rows')) vec # To convert column-major packed RGBA to an R array, use the same ordering # for the dimensions, but also need to specify length along each dimension aperm_vector_to_array(vec, src = c(planes = 4, cols = 3, rows = 2))# create a small RGBA array in R with each # plane of the array holding a different colour channel arr <- array(c(paste0('r', 1:6), paste0('g', 1:6), paste0('b', 1:6), paste0('a', 1:6)), c(2, 3, 4)) arr # A very common C ordering is packaged RGBA data in column major format # i.e. Iterate over: planes, then columns, then rows # i.e. # start at first element # (plane1, plane2, plane3, plane4) # go to next column # (plane1, plane2, plane3, plane4) # go to next column # ... # when last column is done # do to next row # Convert to packed RGBA in column-major format vec <- aperm_array_to_vector(arr, dst = c('planes', 'cols', 'rows')) vec # To convert column-major packed RGBA to an R array, use the same ordering # for the dimensions, but also need to specify length along each dimension aperm_vector_to_array(vec, src = c(planes = 4, cols = 3, rows = 2))
Permute a linear vector of data into an R array
aperm_vector_to_array(x, src, flipy = FALSE, simplify_matrix = TRUE)aperm_vector_to_array(x, src, flipy = FALSE, simplify_matrix = TRUE)
x |
vector |
src |
Specification of source dimensions in the order of presentation
in the source data. This must a named integer vector with
the names "planes", "rows", "cols" (and their corresponding sizes)
in the order in which they occur in the data. The first
named element must always be "planes". Use |
flipy |
flip the array vertically. Default: FALSE |
simplify_matrix |
If the resulting array only has a single plane, should this be simplified to a matrix? Default: TRUE |
array or matrix
Other data permutation functions:
aperm_array_to_vector(),
flip_endian()
# Convert a vector of packed RGB data to an array with 3 planes x <- c( 'r0', 'g0', 'b0', 'r1', 'g1', 'b1', 'r2', 'g2', 'b2', 'r3', 'g3', 'b3', 'r4', 'g4', 'b4', 'r5', 'g5', 'b5' ) aperm_vector_to_array(x, src = c(planes = 3, cols = 3, rows = 2))# Convert a vector of packed RGB data to an array with 3 planes x <- c( 'r0', 'g0', 'b0', 'r1', 'g1', 'b1', 'r2', 'g2', 'b2', 'r3', 'g3', 'b3', 'r4', 'g4', 'b4', 'r5', 'g5', 'b5' ) aperm_vector_to_array(x, src = c(planes = 3, cols = 3, rows = 2))
This will create a new vector with the values reversed within the given block size. This can be used for changing the endianness of a set of values
flip_endian(x, size)flip_endian(x, size)
x |
vector. Usually a raw vector, but can be any type |
size |
block size. Usually a power of 2. |
A vector of the same type as the initial vector with the values within each block reversed.
Other data permutation functions:
aperm_array_to_vector(),
aperm_vector_to_array()
vec <- c(1, 2, 3, 4) flip_endian(vec, 1) # should give: c(1, 2, 3, 4) flip_endian(vec, 2) # should give: c(2, 1, 4, 3) flip_endian(vec, 4) # should give: c(4, 3, 2, 1)vec <- c(1, 2, 3, 4) flip_endian(vec, 1) # should give: c(1, 2, 3, 4) flip_endian(vec, 2) # should give: c(2, 1, 4, 3) flip_endian(vec, 4) # should give: c(4, 3, 2, 1)
fprintf_raw() writes the text without a nul-terminator. fprintf()
writes a nul-terminator
fprintf(con, fmt, ..., sep = "\n", useBytes = FALSE) fprintf_raw(con, fmt, ..., sep = "\n", useBytes = FALSE)fprintf(con, fmt, ..., sep = "\n", useBytes = FALSE) fprintf_raw(con, fmt, ..., sep = "\n", useBytes = FALSE)
con |
Connection object or raw vector. When con is a raw vector, new
data will be appended to the vector and returned.
Connection objects can be
created with |
fmt |
a character vector of format strings. See |
... |
values to be passed in to |
sep |
If there are multiple strings to be printed, this separated will be written after each one. |
useBytes |
See |
If con is a connection then this connection is returned invisibly.
If con is a raw vector then new data is appended to this vector
Other data output functions:
write_f64(),
write_hex(),
write_raw(),
write_uint8(),
write_utf8()
con <- rawConnection(raw(), "wb") fprintf(con, "%i,%6.2f", 1, 3.14159) close(con)con <- rawConnection(raw(), "wb") fprintf(con, "%i,%6.2f", 1, 3.14159) close(con)
Read floating point numbers into a standard R vector of doubles
read_f64(con, n = 1, endian = NULL) read_f32(con, n = 1, endian = NULL) read_f16(con, n = 1, endian = NULL) read_bfloat(con, n = 1, endian = NULL) read_dbl(con, n = 1, endian = NULL) read_float(con, n = 1, endian = NULL) read_half(con, n = 1, endian = NULL)read_f64(con, n = 1, endian = NULL) read_f32(con, n = 1, endian = NULL) read_f16(con, n = 1, endian = NULL) read_bfloat(con, n = 1, endian = NULL) read_dbl(con, n = 1, endian = NULL) read_float(con, n = 1, endian = NULL) read_half(con, n = 1, endian = NULL)
con |
Connection object or raw vector. Connection objects can be
created with |
n |
Number of elements to read. Default: 1 |
endian |
Ordering of bytes within the file when reading multi-byte values.
Possible values: 'big' or 'little'.
Default: NULL indicates that
endian option should be retrieved from the connection object if possible
(where the user has used |
8 byte floating point numbers. read_f64()
also available as read_dbl()
4 byte floating point numbers. read_f32()
also available as read_float()
2 byte floating point numbers. read_f16()
also available as read_half(). Consists of 1 sign bit,
5 bits for exponent and 10 bits for fraction.
2 byte floating point numbers in the bfloat format read_bfloat().
Consits of 1 sign bit, 8 bits fo exponent and 7 bits for fraction.
vector of double precision floating point numbers
Other data input functions:
read_hex(),
read_raw(),
read_str(),
read_uint8(),
scan_dbl()
# Raw vector with 16 bytes (128 bits) of dummy data data <- as.raw(1:16) con <- rawConnection(data, 'rb') read_f64(con, n = 1) # Read a 64-bit double-precision number read_f16(con, n = 4) # Read 4 x 16-bit half-precision number close(con)# Raw vector with 16 bytes (128 bits) of dummy data data <- as.raw(1:16) con <- rawConnection(data, 'rb') read_f64(con, n = 1) # Read a 64-bit double-precision number read_f16(con, n = 4) # Read 4 x 16-bit half-precision number close(con)
Read bytes as hexadecimal strings
read_hex(con, n = 1, size = 1, endian = NULL)read_hex(con, n = 1, size = 1, endian = NULL)
con |
Connection object or raw vector. Connection objects can be
created with |
n |
Number of hexadecimal strings to read. Default: 1 |
size |
size in bytes of each string. Default: 1 |
endian |
Ordering of bytes within the file when reading multi-byte values.
Possible values: 'big' or 'little'.
Default: NULL indicates that
endian option should be retrieved from the connection object if possible
(where the user has used |
vector of hexadecimal character strings
Other data input functions:
read_f64(),
read_raw(),
read_str(),
read_uint8(),
scan_dbl()
con <- rawConnection(as.raw(1:4)) read_hex(con, n = 4, size = 1) close(con) con <- rawConnection(as.raw(1:4)) read_hex(con, n = 1, size = 4) close(con) con <- rawConnection(as.raw(1:4)) read_hex(con, n = 2, size = 2, endian = "big") close(con)con <- rawConnection(as.raw(1:4)) read_hex(con, n = 4, size = 1) close(con) con <- rawConnection(as.raw(1:4)) read_hex(con, n = 1, size = 4) close(con) con <- rawConnection(as.raw(1:4)) read_hex(con, n = 2, size = 2, endian = "big") close(con)
Read raw bytes
read_raw(con, n = 1)read_raw(con, n = 1)
con |
Connection object or raw vector. Connection objects can be
created with |
n |
Number of elements to read. Default: 1 |
raw vector
Other data input functions:
read_f64(),
read_hex(),
read_str(),
read_uint8(),
scan_dbl()
con <- rawConnection(charToRaw("hello12.3")) read_raw(con, 5) close(con)con <- rawConnection(charToRaw("hello12.3")) read_raw(con, 5) close(con)
Read character string from a connection.
read_str(con) read_str_raw(con, n) read_utf8(con) read_utf8_raw(con, n)read_str(con) read_str_raw(con, n) read_utf8(con) read_utf8_raw(con, n)
con |
Connection object or raw vector. Connection objects can be
created with |
n |
number of characters to read. |
Functions which have a suffix of _raw are for handling character
strings without a nul-terminator.
single character string
Other data input functions:
read_f64(),
read_hex(),
read_raw(),
read_uint8(),
scan_dbl()
con <- rawConnection(c(charToRaw("hello12.3"), as.raw(0))) read_str(con) close(con) con <- rawConnection(charToRaw("hello12.3")) read_str_raw(con, 5) close(con) con <- rawConnection(c(charToRaw("hello12.3"), as.raw(0))) read_utf8(con) close(con) con <- rawConnection(charToRaw("hello12.3")) read_utf8_raw(con, 3) close(con)con <- rawConnection(c(charToRaw("hello12.3"), as.raw(0))) read_str(con) close(con) con <- rawConnection(charToRaw("hello12.3")) read_str_raw(con, 5) close(con) con <- rawConnection(c(charToRaw("hello12.3"), as.raw(0))) read_utf8(con) close(con) con <- rawConnection(charToRaw("hello12.3")) read_utf8_raw(con, 3) close(con)
Read integer values into a standard R vector of integers or alternate containers for large types
read_uint8(con, n = 1, endian = NULL) read_int8(con, n = 1, endian = NULL) read_int16(con, n = 1, endian = NULL) read_uint16(con, n = 1, endian = NULL) read_int32(con, n = 1, endian = NULL) read_uint32(con, n = 1, endian = NULL, promote = NULL) read_int64(con, n = 1, endian = NULL, promote = NULL, bounds_check = NULL) read_uint64(con, n = 1, endian = NULL, promote = NULL, bounds_check = NULL)read_uint8(con, n = 1, endian = NULL) read_int8(con, n = 1, endian = NULL) read_int16(con, n = 1, endian = NULL) read_uint16(con, n = 1, endian = NULL) read_int32(con, n = 1, endian = NULL) read_uint32(con, n = 1, endian = NULL, promote = NULL) read_int64(con, n = 1, endian = NULL, promote = NULL, bounds_check = NULL) read_uint64(con, n = 1, endian = NULL, promote = NULL, bounds_check = NULL)
con |
Connection object or raw vector. Connection objects can be
created with |
n |
Number of elements to read. Default: 1 |
endian |
Ordering of bytes within the file when reading multi-byte values.
Possible values: 'big' or 'little'.
Default: NULL indicates that
endian option should be retrieved from the connection object if possible
(where the user has used |
promote |
For 'uin32', 'int64' and 'uint64' types, the range of possible
values exceeds R's standard integer type. For these integer types,
values will be promoted to a different container type.
Possible options 'dbl', 'raw', 'hex' and 'bit64'.
Default: NULL indicates that
this option should be retrieved from the connection object if possible
(where the user has used
|
bounds_check |
Check values lie within bounds of the given type.
Default: NULL indicates that
this option should be retrieved from the connection object if possible
(where the user has used |
read_int8() and read_uint8()
read_int16() and read_uint16()
read_int32() and read_uint32()
read_int64() and read_uint64()
Integer data. Usually in standard R integer vector but depending on
the promote option may be returned in alternate formats
Other data input functions:
read_f64(),
read_hex(),
read_raw(),
read_str(),
scan_dbl()
# Raw vector with 16 bytes (128 bits) of dummy data data <- as.raw(c(1:7, 0, 1:8)) con <- rawConnection(data, 'rb') read_int64(con, n = 1) read_uint8(con, n = 4) close(con)# Raw vector with 16 bytes (128 bits) of dummy data data <- as.raw(c(1:7, 0, 1:8)) con <- rawConnection(data, 'rb') read_int64(con, n = 1) read_uint8(con, n = 4) close(con)
A lightweight wrapper around the standard scan() function.
scan_dbl(con, n = 1, quiet = TRUE, ...) scan_int(con, n = 1, quiet = TRUE, ...) scan_str(con, n = 1, quiet = TRUE, ...)scan_dbl(con, n = 1, quiet = TRUE, ...) scan_int(con, n = 1, quiet = TRUE, ...) scan_str(con, n = 1, quiet = TRUE, ...)
con |
Connection object or raw vector. Connection objects can be
created with |
n |
Number of elements to read. Default: 1 |
quiet |
Default: TRUE |
... |
further arguments passed to |
These functions are useful when the numeric values are encoded as strings written
to the file, rather than as binary data. Values must be delimited
by whitespace or other specified separator. See documentation for
scan() for more information.
Value of the given type
Other data input functions:
read_f64(),
read_hex(),
read_raw(),
read_str(),
read_uint8()
con <- textConnection(r"( type 20 30 3.14159 )") scan_str(con) scan_int(con) scan_int(con) scan_dbl(con) close(con)con <- textConnection(r"( type 20 30 3.14159 )") scan_str(con) scan_int(con) scan_int(con) scan_dbl(con) close(con)
For this connection, set the response when values do not fit into given type before writing.
set_bounds_check(con, bounds_check = "error")set_bounds_check(con, bounds_check = "error")
con |
Connection object or raw vector. Connection objects can be
created with |
bounds_check |
Default bounds checking behaviour. One of: 'ignore', 'warn', 'error'.
Default: 'error'.
This default may be over-ridden by specifying
the
|
Modified connection object
Other connection configuration functions:
set_endian(),
set_eof_check(),
set_integer_promotion(),
set_na_check()
# Open a connection and configure it so out-of-bounds values # will cause a warning only. con <- rawConnection(as.raw(1:8), "rb") con <- set_bounds_check(con, bounds_check = "warn") # This line attempts to read a value from the connection which # is too large to store in a double precision floating point without # loss of integer precision. # Usually this would cause an error to be raised, but the 'bounds_check' # option has been set to give a warning only. read_uint64(con, n = 1, promote = "dbl") close(con)# Open a connection and configure it so out-of-bounds values # will cause a warning only. con <- rawConnection(as.raw(1:8), "rb") con <- set_bounds_check(con, bounds_check = "warn") # This line attempts to read a value from the connection which # is too large to store in a double precision floating point without # loss of integer precision. # Usually this would cause an error to be raised, but the 'bounds_check' # option has been set to give a warning only. read_uint64(con, n = 1, promote = "dbl") close(con)
Tag a connection with the preferred endianness
set_endian(con, endian = "little")set_endian(con, endian = "little")
con |
Connection object or raw vector. Connection objects can be
created with |
endian |
Default endianness to assign to this connection. One of either
"little" or "big". Default: "little".
This default may be over-ridden by specifying
the |
Modified connection object
Other connection configuration functions:
set_bounds_check(),
set_eof_check(),
set_integer_promotion(),
set_na_check()
# Open a connection and configure it so all subsequent read/write operations # use big-endian ordering. con <- rawConnection(as.raw(c(0, 1, 0, 1)), "rb") con <- set_endian(con, endian = "big") # Future reads will be be big endian read_uint16(con, n = 1) # Unless over-ridden during the read read_uint16(con, n = 1, endian = "little") close(con)# Open a connection and configure it so all subsequent read/write operations # use big-endian ordering. con <- rawConnection(as.raw(c(0, 1, 0, 1)), "rb") con <- set_endian(con, endian = "big") # Future reads will be be big endian read_uint16(con, n = 1) # Unless over-ridden during the read read_uint16(con, n = 1, endian = "little") close(con)
When the end-of-file is reached and values are requested from the connection,
how should a read call check and react?
set_eof_check(con, eof_check = "error")set_eof_check(con, eof_check = "error")
con |
Connection object or raw vector. Connection objects can be
created with |
eof_check |
Default EOF checking behaviour. One of: 'ignore', 'warn', 'error' Default: 'error'.
|
Note: R's readBin() does not necessarily react when the end-of-file
is reached, and in many situations all that will happen is that fewer
data values will be returned than what was requested.
By setting this option on the connection, work is done to check the count of returned values after every call to try and detect when the end-of-file has been reached.
Modified connection object
Other connection configuration functions:
set_bounds_check(),
set_endian(),
set_integer_promotion(),
set_na_check()
# Open a connection and configure it so reading past the end-of-file # ignored, and operations simply return fewer values than requested con <- rawConnection(as.raw(1:8), "rb") con <- set_eof_check(con, eof_check = "ignore") # There are only 8 bytes in the connection. # Attempting to read 12 bytes will reach the end of the file. # Because "eof_check" has been set to "ignore", there will just be # silent truncation of the data read_uint8(con, n = 12) # The connection can be configured to raise an error or warning # when EOF is reached con <- set_eof_check(con, eof_check = "warn") read_uint8(con, n = 12) close(con)# Open a connection and configure it so reading past the end-of-file # ignored, and operations simply return fewer values than requested con <- rawConnection(as.raw(1:8), "rb") con <- set_eof_check(con, eof_check = "ignore") # There are only 8 bytes in the connection. # Attempting to read 12 bytes will reach the end of the file. # Because "eof_check" has been set to "ignore", there will just be # silent truncation of the data read_uint8(con, n = 12) # The connection can be configured to raise an error or warning # when EOF is reached con <- set_eof_check(con, eof_check = "warn") read_uint8(con, n = 12) close(con)
Tag a connection with the preferred integer promotion method for types larger that R's integer type i.e. uint32, uint64, int64
set_integer_promotion(con, uint32 = "dbl", int64 = "dbl", uint64 = "dbl")set_integer_promotion(con, uint32 = "dbl", int64 = "dbl", uint64 = "dbl")
con |
Connection object or raw vector. Connection objects can be
created with |
uint32, int64, uint64
|
specifiy separate promotion methods for these types
One of: 'dbl', 'hex', 'raw' and 'bit64' (for 64-bit types only) Default: 'dbl'.
This default may be over-ridden by specifying
the
|
Modified connection object
Other connection configuration functions:
set_bounds_check(),
set_endian(),
set_eof_check(),
set_na_check()
# Open a connection and configure it so all 'uint32' values are # read as floating point and all all 'uint64' values are read as hexadecimal strings con <- rawConnection(as.raw(c(1:7, 0, 1:7, 0, 1:7, 0, 1:7, 0)), "rb") con <- set_integer_promotion(con, uint32 = "dbl", uint64 = "hex") # Future reads of uint64 will return hex strings read_uint64(con, n = 2) # Unless over-ridden during the read read_uint64(con, n = 1, promote = "dbl") close(con)# Open a connection and configure it so all 'uint32' values are # read as floating point and all all 'uint64' values are read as hexadecimal strings con <- rawConnection(as.raw(c(1:7, 0, 1:7, 0, 1:7, 0, 1:7, 0)), "rb") con <- set_integer_promotion(con, uint32 = "dbl", uint64 = "hex") # Future reads of uint64 will return hex strings read_uint64(con, n = 2) # Unless over-ridden during the read read_uint64(con, n = 1, promote = "dbl") close(con)
For the majority of binary file formats, there is never the need to
store or retrieve an NA value. The default behaviour of this
package is to raise an error if any attempt is made to write an NA
to file. Set this option to "warn" or "ignore" to modify this.
set_na_check(con, na_check)set_na_check(con, na_check)
con |
Connection object or raw vector. Connection objects can be
created with |
na_check |
Default NA checking behaviour. One of: 'ignore', 'warn', 'error'
Default: 'error'.
This default may be over-ridden by specifying
the
|
Modified connection object
Other connection configuration functions:
set_bounds_check(),
set_endian(),
set_eof_check(),
set_integer_promotion()
# Open a connection and configure it so any attempt to write an NA # value will cause a warning only (the default behaviour is to raise an error) con <- rawConnection(raw(), "wb") con <- set_na_check(con, na_check = "warn") # This write should work without issues write_dbl(con, c(1, 2, 3, 4)) # This write will cause a warning write_dbl(con, c(1, 2, 3, NA)) close(con)# Open a connection and configure it so any attempt to write an NA # value will cause a warning only (the default behaviour is to raise an error) con <- rawConnection(raw(), "wb") con <- set_na_check(con, na_check = "warn") # This write should work without issues write_dbl(con, c(1, 2, 3, 4)) # This write will cause a warning write_dbl(con, c(1, 2, 3, NA)) close(con)
Convert values to the given type and write to a connection
write_f64(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_dbl(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_f32(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_single(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_f16(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_half(con, x, endian = NULL, bounds_check = NULL, na_check = NULL)write_f64(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_dbl(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_f32(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_single(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_f16(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_half(con, x, endian = NULL, bounds_check = NULL, na_check = NULL)
con |
Connection object or raw vector. When con is a raw vector, new
data will be appended to the vector and returned.
Connection objects can be
created with |
x |
vector to write |
endian |
Ordering of bytes within the file when reading multi-byte values.
Possible values: 'big' or 'little'.
Default: NULL indicates that
endian option should be retrieved from the connection object if possible
(where the user has used |
bounds_check |
Check values lie within bounds of the given type.
Default: NULL indicates that
this option should be retrieved from the connection object if possible
(where the user has used |
na_check |
Check for NAs in the data to be written.
Default: NULL indicates that
this option should be retrieved from the connection object if possible
(where the user has used |
If con is a connection then this connection is returned invisibly.
If con is a raw vector then new data is appended to this vector
Other data output functions:
fprintf(),
write_hex(),
write_raw(),
write_uint8(),
write_utf8()
con <- file(tempfile(), "wb") write_f64(con, c(1, 2, 3, 4)) close(con)con <- file(tempfile(), "wb") write_f64(con, c(1, 2, 3, 4)) close(con)
Write hexadecimal string as raw bytes
write_hex(con, x, endian = NULL)write_hex(con, x, endian = NULL)
con |
Connection object or raw vector. When con is a raw vector, new
data will be appended to the vector and returned.
Connection objects can be
created with |
x |
vector to write |
endian |
Ordering of bytes within the file when reading multi-byte values.
Possible values: 'big' or 'little'.
Default: NULL indicates that
endian option should be retrieved from the connection object if possible
(where the user has used |
If con is a connection then this connection is returned invisibly.
If con is a raw vector then new data is appended to this vector
Other data output functions:
fprintf(),
write_f64(),
write_raw(),
write_uint8(),
write_utf8()
con <- file(tempfile(), "wb") write_hex(con, c("ff80", "0102")) close(con)con <- file(tempfile(), "wb") write_hex(con, c("ff80", "0102")) close(con)
Write raw bytes
write_raw(con, x, bounds_check = NULL)write_raw(con, x, bounds_check = NULL)
con |
Connection object or raw vector. When con is a raw vector, new
data will be appended to the vector and returned.
Connection objects can be
created with |
x |
vector to write |
bounds_check |
Check values lie within bounds of the given type.
Default: NULL indicates that
this option should be retrieved from the connection object if possible
(where the user has used |
If con is a connection then this connection is returned invisibly.
If con is a raw vector then new data is appended to this vector
Other data output functions:
fprintf(),
write_f64(),
write_hex(),
write_uint8(),
write_utf8()
con <- file(tempfile(), "wb") write_raw(con, as.raw(1:4)) write_raw(con, 1:4) close(con)con <- file(tempfile(), "wb") write_raw(con, as.raw(1:4)) write_raw(con, 1:4) close(con)
Convert values to the given type and write to a connection
write_uint8(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_int8(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_uint16(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_int16(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_uint32(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_int32(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_uint64(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_int64(con, x, endian = NULL, bounds_check = NULL, na_check = NULL)write_uint8(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_int8(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_uint16(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_int16(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_uint32(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_int32(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_uint64(con, x, endian = NULL, bounds_check = NULL, na_check = NULL) write_int64(con, x, endian = NULL, bounds_check = NULL, na_check = NULL)
con |
Connection object or raw vector. When con is a raw vector, new
data will be appended to the vector and returned.
Connection objects can be
created with |
x |
vector to write |
endian |
Ordering of bytes within the file when reading multi-byte values.
Possible values: 'big' or 'little'.
Default: NULL indicates that
endian option should be retrieved from the connection object if possible
(where the user has used |
bounds_check |
Check values lie within bounds of the given type.
Default: NULL indicates that
this option should be retrieved from the connection object if possible
(where the user has used |
na_check |
Check for NAs in the data to be written.
Default: NULL indicates that
this option should be retrieved from the connection object if possible
(where the user has used |
If con is a connection then this connection is returned invisibly.
If con is a raw vector then new data is appended to this vector
Other data output functions:
fprintf(),
write_f64(),
write_hex(),
write_raw(),
write_utf8()
con <- file(tempfile(), "wb") write_uint8(con, 1:4) close(con)con <- file(tempfile(), "wb") write_uint8(con, 1:4) close(con)
write_utf8_raw() writes the string without a nul-terminator.
write_utf8() includes a nul-terminator
write_utf8(con, x) write_utf8_raw(con, x)write_utf8(con, x) write_utf8_raw(con, x)
con |
Connection object or raw vector. When con is a raw vector, new
data will be appended to the vector and returned.
Connection objects can be
created with |
x |
single character string |
If con is a connection then this connection is returned invisibly.
If con is a raw vector then new data is appended to this vector
Other data output functions:
fprintf(),
write_f64(),
write_hex(),
write_raw(),
write_uint8()
con <- file(tempfile(), "wb") write_utf8(con, "hello") close(con)con <- file(tempfile(), "wb") write_utf8(con, "hello") close(con)