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readr (version 0.2.0)

read_log: Read common/combined log file.

Description

This is a fairly standard format for log files - it uses both quotes and square brackets for quoting, and there may be literal quotes embedded in a quoted string. The dash, "-", is used for missing values.

Usage

read_log(file, col_names = FALSE, col_types = NULL, skip = 0, n_max = -1, progress = interactive())

Arguments

file
Either a path to a file, a connection, or literal data (either a single string or a raw vector).

Files ending in .gz, .bz2, .xz, or .zip will be automatically uncompressed. Files starting with http://, https://, ftp://, or ftps:// will be automatically downloaded. Remote gz files can also be automatically downloaded & decompressed.

Literal data is most useful for examples and tests. It must contain at least one new line to be recognised as data (instead of a path).

col_names
Either TRUE, FALSE or a character vector of column names.

If TRUE, the first row of the input will be used as the column names, and will not be included in the data frame. If FALSE, column names will be generated automatically: X1, X2, X3 etc.

If col_names is a character vector, the values will be used as the names of the columns, and the first row of the input will be read into the first row of the output data frame.

col_types
One of NULL, a cols, specification of a string. See vignette("column-types") for more details.

If NULL, all column types will be imputed from the first 1000 rows on the input. This is convenient (and fast), but not robust. If the imputation fails, you'll need to supply the correct types yourself.

If a column specification created by cols, it must contain one "collector" for each column. If you only want to read a subset of the columns, use cols_only.

Alternatively, you can use a compact string representation where each character represents one column: c = character, i = integer, n = number, d = double, l = logical, D = date, T = date time, t = time, ? = guess, or _/- to skip the column.

skip
Number of lines to skip before reading data.
n_max
Maximum number of records to read.
progress
Display a progress bar? By default it will only display in an interactive session. The display is updated every 50,000 values and will only display if estimated reading time is 5 seconds or more.

Examples

Run this code
read_log(system.file("extdata/example.log", package = "readr"))

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