= R readr =

The `readr` package provides [[R/FileIO|file I/O]] functions.

<<TableOfContents>>

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== Installation ==

`readr` is commonly used through [[R/Tidyverse|Tidyverse]].

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== Usage ==

||'''Data Format'''||'''Ingress Example'''                        ||'''Outgress Example'''                  ||
||Native R         ||`read_rds("data.rds")`                       ||`write_rds(df, "data.rds")`             ||
||Comma-delimited  ||`read_csv("data.csv")`                       ||`write_csv(df, "data.csv")`             ||
||Tab-delimited    ||`read_tsv("data.tsv")`                       ||`write_tsv(df, "data.tsv")`             ||
||Any delimiter    ||`read_delim("data.txt", delim="|")`          ||`write_delim(df, "data.txt", delim="|")`||
||Fixed width      ||`read_fwf("data.txt", fwf_widths(c(2,2,NA)))`||N/A                                     ||

These functions (aside from the native R ones) all take these arguments:
 * If `col_names` is a [[R/DataTypes#Numeric|logical]], it toggles whether the first row is read as a header.
 * If `col_names` is a [[R/DataTypes#Compositions|vector]], the variables are named accordingly.
 * `skip` causes the parser to skip some number of rows.
 * `n_max` causes the parser to stop after some number of rows.
 * `guess_max` is the number of rows to parse before determining the storage type. To parse all data before type casting, try `guess_max = Inf`.
 * `col_select` subsets the columns to store. It should be specified like `col_select = c(1,2,3)`. Something like `col_select = c(foo, bar, baz)` can be used if there is header information.



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CategoryRicottone