Create a mooring-release object

Create a mooring-release object, either by looking up a known object from the database, or by defining a new type. Area is formulated as length*width, for consistency with Dewey's Matlab code.

release(
  model = "EG&G 723a",
  buoyancy = NULL,
  height = NULL,
  area = NULL,
  CD = NULL,
  source = NULL,
  originalName = NULL
)

Arguments

model

character value indicating the type of release. There are three possibilities for model. (1) If this is "?", then the function returns a vector of permitted character values. (2) If this is "?X", where X is a set of characters, then findElement() is called to do a fuzzy search, with the search argument set to "release". (3) If it is recognized, i.e. if that type is stored in data(mooringElements), then the that stored value is used, and all other arguments to this function are ignored. (4) Otherwise, a new release object is created, using values specified in the other arguments (all of which must be supplied).

buoyancy

numeric value indicating buoyancy. For wire elements, this is buoyancy per length, expressed in kg/m. For other elements, it is buoyancy, expressed in kg. Note that buoyancy is ignored if model is recognized.

height

numeric value for the height (in m) of the element. This value is used in the computation of the mooring geometry. In some cases, as e.g. in Dewey-derived data that have "diameter" tabulated as zero, it is also used in the computation of the area of the element, as height*width. Note that height is ignored if model is recognized.

area

a numerical value indicating the horizontal instrument area in \(m^2\).

CD

numeric value (unitless) for the drag coefficient. Note that CD is ignored if model is recognized.

source

character value indicating the source of the data.

originalName

character value indicating the original model name.

Value

release returns an object of the "mooringElement" class and "release" subclass.

See also

Other functions that create mooring elements: anchor(), chain(), connector(), float(), instrument(), misc(), wire()

Author

Dan Kelley

Examples

library(mooring)
# List known wire types
release("?")
#>  [1] "CDMS AR"                    "Dble Mesotech501"          
#>  [3] "EG&G 723a"                  "EG&G 723a with tension bar"
#>  [5] "EG&G 8242"                  "InterOcean1090ED"          
#>  [7] "Mesotech AR"                "Oceano AR191"              
#>  [9] "Oceano AR2500"              "Oceano AR261"              
#> [11] "Oceano RT-121"              "Oceano RT-161"             
#> [13] "benthos 865a"               "benthos 965a"              
#> [15] "benthos 966a and 866a"      "double 8242"               
#> [17] "double AR-191"              "double AR/EG&G"            
#> [19] "double RT-161"              "vr2w with float collar"