geographiclib (version 0.4.1)

dms_decode: Convert between degrees and DMS (degrees, minutes, seconds) representation

Description

Parse strings representing degrees, minutes, and seconds and return the angle in degrees. Format an angle in degrees as degrees, minutes, and seconds strings.

Usage

dms_decode(x)
dms_decode_latlon(dmsa, dmsb, longfirst = FALSE)
dms_decode_angle(x)
dms_decode_azimuth(x)
dms_encode(x, prec = 5L, component = NULL, indicator = "none", sep = "")
dms_split(x, seconds = FALSE)
dms_combine(d, m = 0, s = 0)

Value

• dms_decode(): Data frame with columns angle (degrees) and indicator (0=NONE, 1=LATITUDE, 2=LONGITUDE)

• dms_decode_latlon(): Data frame with columns lat and lon (degrees)

• dms_decode_angle(): Numeric vector of angles in degrees

• dms_decode_azimuth(): Numeric vector of azimuths in degrees (range -180 to 180)

• dms_encode(): Character vector of DMS strings

• dms_split(): Data frame with columns d, m, and optionally s

• dms_combine(): Numeric vector of angles in degrees

Arguments

x

Character vector of DMS strings to parse, or numeric vector of angles in degrees to encode.

dmsa, dmsb

Character vectors of DMS strings for latitude/longitude parsing.

longfirst

Logical; if TRUE, assume longitude is given before latitude when no hemisphere designators are present.

prec

Integer precision for output strings. For dms_encode() this is the number of digits after the decimal point for the trailing component. For automatic encoding, prec < 2 gives degrees, prec 2-3 gives minutes, prec >= 4 gives seconds.

component

Character indicating the trailing unit: "degree", "minute", or "second".

indicator

Character indicating formatting: "none" (signed result), "latitude" (trailing N/S), "longitude" (trailing E/W), "azimuth" (0-360, no sign), or "number" (plain number).

sep

Character to use as DMS separator instead of d, ', ". Use ":" for colon-separated output.

seconds

Logical; if TRUE, split into degrees, minutes, and seconds. If FALSE (default), split into degrees and minutes only.

d, m, s

Numeric vectors of degrees, minutes, and seconds.

Details

Input Formats

The dms_decode() function accepts various input formats:

• Degrees, minutes, seconds: "40d26'47\"N", "40°26'47\"N"

• Degrees and minutes: "40d26.783'N", "40:26.783N"

• Decimal degrees: "40.446N", "-40.446"

• Colon-separated: "40:26:47", "-74:0:21.5"

Hemisphere designators (N, S, E, W) can appear at the beginning or end. Many Unicode symbols are supported for degrees, minutes, and seconds. See the GeographicLib DMS documentation for the full list of accepted symbols.

Precision and Components

For dms_encode(), the prec parameter controls decimal places in the trailing component:

• prec = 0: whole degrees/minutes/seconds

• prec = 1: one decimal place

• prec = 2: two decimal places, etc.

For automatic component selection:

• prec < 2: output in degrees

• prec = 2, 3: output in degrees and minutes

• prec >= 4: output in degrees, minutes, and seconds

See Also

geocoords_parse() for parsing complete coordinate strings

Examples

# Parse DMS strings
dms_decode("40d26'47\"N")
dms_decode(c("40:26:47", "-74:0:21.5", "51d30'N"))

# Parse latitude/longitude pairs
dms_decode_latlon("40d26'47\"N", "74d0'21.5\"W")

# Parse angles (no hemisphere designator)
dms_decode_angle(c("45:30:0", "123d45'6\""))

# Parse azimuths (E/W allowed)
dms_decode_azimuth(c("45:30:0", "90W", "45E"))

# Encode to DMS strings
dms_encode(40.446, indicator = "latitude")
dms_encode(-74.006, indicator = "longitude")
dms_encode(c(40.446, -74.006), prec = 2)

# With colon separator
dms_encode(40.446, sep = ":")

# Split angle into components
dms_split(40.446)
dms_split(c(40.446, -74.006), seconds = TRUE)

# Combine components to decimal degrees
dms_combine(40, 26, 47)
dms_combine(d = c(40, -74), m = c(26, 0), s = c(47, 21.5))