Latitude or Longitude Attribute for Coords
latlon.Rdlatlon()<- adds the attribute "latlon" to objects of class
"coords", or modifies an existing "latlon" attribute.
Arguments
- cd
object of class
"coords".- value
a
logicalvector of length1orlength(cd).
Details
Attribute "latlon" is a logical vector of length 1 or length(cd)
for which TRUE values represent latitude and FALSE values represent longitude.
Setting this attribute to any other length will result in an error. A logical vector of
length 1L signifies that values are all latitude if TRUE, or all longitude if
FALSE.
This attribute is used in formatting printed output and also by
validate(). Indeed, the values of cd are revalidated every time
attribute "latlon" is added or changed.
See also
"coords".
Examples
## Continuing example from `coords()`...
## Create "coords" object in degrees and minutes
as_coords(dm, fmt = 2)
#> Nelson's Column 51°30.4659′ (N/E)
#> Ostravice 49°32.7726′ (N/E)
#> Tally Ho 48°06.4339′ (N/E)
#> Washington Monument 38°53.3696′ (N/E)
#> Null Island 0°00.0000′ (N/E)
#> Tristan da Cunha 37°06.7044′ (S/W)
#> Mawson Peak 53°06.2869′ (S/W)
#> Silvio Pettirossi International Airport 25°14.4093′ (S/W)
#> Nelson's Column 0°07.6754′ (S/W)
#> Ostravice 18°23.9137′ (N/E)
#> Tally Ho 122°46.7203′ (S/W)
#> Washington Monument 77°02.1145′ (S/W)
#> Null Island 0°00.0000′ (N/E)
#> Tristan da Cunha 12°17.3178′ (S/W)
#> Mawson Peak 73°31.0370′ (N/E)
#> Silvio Pettirossi International Airport 57°31.1536′ (S/W)
## Set "latlon" attribute to FALSE, length 1; all values are longitude
latlon(dm) <- FALSE
dm
#> Nelson's Column 51°30.4659′ E
#> Ostravice 49°32.7726′ E
#> Tally Ho 48°06.4339′ E
#> Washington Monument 38°53.3696′ E
#> Null Island 0°00.0000′ E
#> Tristan da Cunha 37°06.7044′ W
#> Mawson Peak 53°06.2869′ W
#> Silvio Pettirossi International Airport 25°14.4093′ W
#> Nelson's Column 0°07.6754′ W
#> Ostravice 18°23.9137′ E
#> Tally Ho 122°46.7203′ W
#> Washington Monument 77°02.1145′ W
#> Null Island 0°00.0000′ E
#> Tristan da Cunha 12°17.3178′ W
#> Mawson Peak 73°31.0370′ E
#> Silvio Pettirossi International Airport 57°31.1536′ W
## Set "latlon" attribute to TRUE (n=8) and FALSE (n=8)
## i.e., 8 each of latitude and longitude
latlon(dm) <- rep(c(TRUE, FALSE), each = 8)
dm
#> Nelson's Column 51°30.4659′ N
#> Ostravice 49°32.7726′ N
#> Tally Ho 48°06.4339′ N
#> Washington Monument 38°53.3696′ N
#> Null Island 0°00.0000′ N
#> Tristan da Cunha 37°06.7044′ S
#> Mawson Peak 53°06.2869′ S
#> Silvio Pettirossi International Airport 25°14.4093′ S
#> Nelson's Column 0°07.6754′ W
#> Ostravice 18°23.9137′ E
#> Tally Ho 122°46.7203′ W
#> Washington Monument 77°02.1145′ W
#> Null Island 0°00.0000′ E
#> Tristan da Cunha 12°17.3178′ W
#> Mawson Peak 73°31.0370′ E
#> Silvio Pettirossi International Airport 57°31.1536′ W
## Reversing latitude and longitude results in an invalid latitude,
## throwing a warning
latlon(dm) <- rep(c(FALSE, TRUE), each = 8)
#> Warning: Validation failed!
dm
#> Warning: Formatting invalid coords!
#> Nelson's Column 51°30.4659′ E
#> Ostravice 49°32.7726′ E
#> Tally Ho 48°06.4339′ E
#> Washington Monument 38°53.3696′ E
#> Null Island 0°00.0000′ E
#> Tristan da Cunha 37°06.7044′ W
#> Mawson Peak 53°06.2869′ W
#> Silvio Pettirossi International Airport 25°14.4093′ W
#> Nelson's Column 0°07.6754′ S
#> Ostravice 18°23.9137′ N
#> Tally Ho 122°46.7203′ S
#> Washington Monument 77°02.1145′ S
#> Null Island 0°00.0000′ N
#> Tristan da Cunha 12°17.3178′ S
#> Mawson Peak 73°31.0370′ N
#> Silvio Pettirossi International Airport 57°31.1536′ S
rm(dm)