count_fields {readr}R Documentation

Count the number of fields in each line of a file

Description

This is useful for diagnosing problems with functions that fail to parse correctly.

Usage

count_fields(file, tokenizer, skip = 0, n_max = -1L)

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 and decompressed.

Literal data is most useful for examples and tests. To be recognised as a path, it must be wrapped with I(), be a string containing at least one new line, or be a vector containing at least one string with a new line.

Using a value of clipboard() will read from the system clipboard.

tokenizer

A tokenizer that specifies how to break the file up into fields, e.g., tokenizer_csv(), tokenizer_fwf()

skip

Number of lines to skip before reading data.

n_max

Optionally, maximum number of rows to count fields for.

Examples

count_fields(readr_example("mtcars.csv"), tokenizer_csv())

[Package readr version 2.0.2 Index]