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Combine Separate Date and Time Columns into One Timestamp

Source: R/combine_datetime.R
combine_datetime.Rd

Many datasets store date and time in separate columns. This function merges them into a single POSIXct column ready for fill_time_gaps(). The date format is detected automatically.

Usage

combine_datetime(
  data,
  date_col = "date",
  time_col = "time",
  new_col = "datetime",
  date_format = NULL,
  time_type = c("hour", "hhmm", "string"),
  tz = "UTC",
  drop_cols = TRUE,
  verbose = TRUE
)

Arguments

data

A data.frame.

date_col

Character. Name of the date column. Supports many formats automatically:

  • "2024-01-31" or "2024/01/31"

  • "31-01-2024" or "31/01/2024"

  • "01-31-2024" or "01/31/2024"

  • "31.01.2024" or "2024.01.31"

  • "31 Jan 2024" or "January 31, 2024"

  • "20240131" (compact)

time_col

Character. Name of the time/hour column.

new_col

Character. Name of the new combined column. Default "datetime".

date_format

Character. Override auto-detection with a strptime format string. Leave NULL (default) to auto-detect.

time_type

Character. How the time column is stored:

  • "hour" - integer 0-23, e.g. 8, 14

  • "hhmm" - integer HHMM, e.g. 830, 1430

  • "string" - character "HH:MM" or "HH:MM:SS"

tz

Character. Timezone. Default "UTC".

drop_cols

Logical. If TRUE (default), remove date_col and time_col after combining.

verbose

Logical (default TRUE).

Value

The original data.frame with a new POSIXct column prepended (and optionally the source columns removed).

Examples

# Hour stored as integer
df <- data.frame(
  date = c("2024-01-01", "2024-01-01", "2024-01-01"),
  hour = c(8L, 9L, 11L),
  temp = c(25.1, 25.4, 26.2)
)
df2 <- combine_datetime(df, date_col = "date", time_col = "hour",
                        time_type = "hour")
#> 
#> ============================================================
#>   STEP : Combine Date + Time into One Column
#> ============================================================
#> 
#>   Date column : date  (format: %Y-%m-%d [auto])
#>   New column  : datetime  (tz: UTC)
#>   Sample      : 2024-01-01 08:00:00
#> 
#>   >> Next: fill_time_gaps()
#> 
df2$datetime
#> [1] "2024-01-01 08:00:00 UTC" "2024-01-01 09:00:00 UTC"
#> [3] "2024-01-01 11:00:00 UTC"

# Time stored as "HH:MM" string
df3 <- data.frame(
  date = c("01/01/2024", "01/01/2024"),
  time = c("08:30", "09:00"),
  val  = c(10, 12)
)
df4 <- combine_datetime(df3, date_col = "date", time_col = "time",
                        time_type = "string")
#> 
#> ============================================================
#>   STEP : Combine Date + Time into One Column
#> ============================================================
#> 
#>   Date column : date  (format: %Y/%m/%d [auto])
#>   New column  : datetime  (tz: UTC)
#>   Sample      : 1-01-20 08:30:00
#> 
#>   >> Next: fill_time_gaps()
#>