countytimezones (version 1.0.0)

calc_local_time: Calculate local time from UTC for US counties

Description

This function inputs date-time values in Coordinated Universal Time (UTC; also known as Zulu Time), along with a vector with county Federal Information Processing Standard (FIPS) codes, and calculates the local date-time as well as the local date based on th UTC date-time.

Usage

calc_local_time(date_time, fips, include_tz = TRUE)

Arguments

date_time

The vector of the date-time of each observation in Coordinated Universal Time (UTC). This vector can either have a POSIXct class or be a character string, with date-time given as four-digit year, two-digit month, two-digit day, two-digit hour, and two-digit minutes (with hours based on a 24-hour system). Examples of acceptable formats include, for the example of 1:00 PM Jan. 2 1999, "199901021300", "1999-01-02 13:00", and "1999/01/02 13:00".

fips

A character vector giving the 5-digit FIPS code of the county associated with each observation. This can be either a string of length 1, if all observations come from the same county, or a vector as long as the date_time vector, if different observations come from different counties.

include_tz

A TRUE / FALSE value specifying whether to include a column with the local time zone (local_tz) in the final output.

Value

This function returns a dataframe with columns for local date-time, local date, and, if specified, local time zone.

Details

This function inputs date-time values in Coordinated Universal Time (UTC; also known as Zulu Time), as well as a single value or vector of FIPS code(s) for the county associated with each observation. It returns a dataframe with columns for local date-time, local date, and, if specified, local time zone.

Examples

calc_local_time(date_time = "1999-01-01 08:00", fips = "36061")

ex_datetime <- c("1999-01-01 08:00", "1999-01-01 09:00",
                 "1999-01-01 10:00")
calc_local_time(date_time = ex_datetime, fips = "36061")

ex_datetime <- c("1999-01-01 08:00", "1999-01-01 09:00",
                 "1999-01-01 10:00")
ex_fips <- c("36061", "17031", "06037")
calc_local_time(date_time = ex_datetime, fips = ex_fips)