| Type: | Package |
| Title: | Read and Write Column Text Format (CTF) |
| Version: | 0.1.0 |
| Date: | 2021-06-21 |
| Maintainer: | Clark Fitzgerald <fitzgerald@csus.edu> |
| Depends: | R (≥ 3.1.0) |
| Imports: | jsonlite, iotools |
| Suggests: | roxygen2, knitr, rmarkdown, testthat |
| Description: | Column Text Format (CTF) is a new tabular data format designed for simplicity and performance. CTF is the simplest column store you can imagine: plain text files for each column in a table, and a metadata file. The underlying plain text means the data is human readable and familiar to programmers, unlike specialized binary formats. CTF is faster than row oriented formats like CSV when loading a subset of the columns in a table. This package provides functions to read and write CTF data from R. |
| License: | MIT + file LICENSE |
| URL: | https://github.com/julianofhernandez/ctf |
| BugReports: | https://github.com/julianofhernandez/ctf |
| VignetteBuilder: | knitr |
| RoxygenNote: | 7.1.1 |
| NeedsCompilation: | no |
| Packaged: | 2021-07-06 23:21:57 UTC; fitzgerald |
| Author: | Clark Fitzgerald 
[aut, cre] |
| Repository: | CRAN |
| Date/Publication: | 2021-07-07 09:00:05 UTC |
Read CTF data
Description
Read external CTF data into the corresponding R data frame.
Usage
read.ctf(location, columns, nrows)
Arguments
location |
location of the CTF data, either a file path to a CTF metadata JSON file, or a directory containing a single CTF metadata JSON file. |
columns |
names of the columns to read. If missing, then read in all columns. |
nrows |
integer, the maximum number of rows to read in. If missing, then read in all rows. |
Value
data frame
See Also
write.ctf to write CTF
Examples
# An example CTF metadata file included in this package
d <- system.file("extdata", "vgsales", "vgsales-metadata.json", package = "ctf")
# Read all the rows and columns
vgsales <- read.ctf(d)
# Read 10 rows of two columns, Name and Rank
vgsales2 <- read.ctf(d, columns = c("Name", "Rank"), nrows = 10)
Write Data Frame To CTF
Description
Save a data frame using Column Text Format
Usage
write.ctf(x, datadir = name, name = deparse(substitute(x)), ...)
Arguments
x |
data frame to write |
datadir |
directory to write the metadata and CTF columns |
name |
table name |
... |
further arguments to |
Value
NULL, used for its side effect
See Also
read.ctf to read CTF, write.table.raw for the underlying functionality, and save for writing any R objects.
Examples
d <- file.path(tempdir(), "iris_ctf_data")
write.ctf(iris, d)
# Same object as iris, but carries around some extra metadata
iris2 <- read.ctf(d)
# This directory contains plain text files for each column in iris
list.files(d)
# Clean up
unlink(d, recursive = TRUE)