Convert characters to dates

Usage

date_convert(
  data,
  cols,
  error_tolerance,
  timeframe = NULL,
  orders,
  modern_excel
)

Arguments

data

A data frame or linelist

cols

date column name(s)

error_tolerance

A number between 0 and 1 indicating the proportion of entries which cannot be identified as dates to be tolerated; if this proportion is exceeded, the original vector is returned, and a message is issued; defaults to 0.4 (40 percent).

timeframe

A vector of 2 values of type date. If provided, date values that do not fall within this timeframe will be set to NA.

orders

The date codes for fine-grained parsing of dates. This allows for parsing of mixed dates. If a list is supplied, that list will be used for successive tries in parsing. Default orders are:

list(
  world_named_months = c("Ybd", "dby"),
  world_digit_months = c("dmy", "Ymd"),
  US_formats         = c("Omdy", "YOmd")
)

modern_excel

When parsing dates from excel, some dates are stored as integers. Modern versions of Excel represent dates as the number of days since 1900-01-01, but pre-2011 Excel for OSX have the origin set at 1904-01-01. If this parameter is TRUE (default), then this assumes that all numeric values represent dates from either a Windows version of Excel or a 2011 or later version of Excel for OSX. Set this parameter to FALSE if the data came from an OSX version of Excel before 2011.

Value

A data frame where the specified columns have been converted into Date.