Description
Usage
Arguments
Details
Value
Author(s)
See Also
Examples
View source: R/sl.mhd.R
This function calculates the Modified Hausdorff Distance between two sea ice edges
 (A,B,cA=,cB=,kA=,kB=,R=1)

A 
A m x 2 array, containing the (lon,lat) coordinates of the m points forming the (first) edge.

B 
A n x 2 array, containing the (lon,lat) coordinates of the n points forming the (second) edge.

cA 
A p x 2 optional array, containing the (lon,lat) coordinates of the p points of the (first) landice interface between ice and land.

cB 
A q x 2 optional array, containing the (lon,lat) coordinates of the q points of the (second) landice interface between ice and land.

kA 
An optional integer that can vary between 1 and the number of points of the segment A (1<kA<m ). This represents the frequency with which the points in A are considered by the algorithm. As example, if kA=2 , every second point is taken into account for the computation of the MHD, neglecting half of them. This parameter can be useful to speed up the computations, expecially when segment A has a shorter spatial step compared to B. However it can affect the accuracy of the calculated MHD, so be careful when using it. DEFAULT > kA = 1

kB 
An optional integer that can vary between 1 and the number of points of the segment B (1<kA<n ). This represents the frequency with which the points in B are considered by the algorithm. As example, if kB=2 , every second point is taken into account for the computation of the MHD, neglecting half of them. This parameter can be useful to speed up the computations, expecially when segment B has a shorter spatial step compared to A. However it can affect the accuracy of the calculated MHD, so be careful when using it. DEFAULT > kB = 1

R 
Radius of the sphere. DEFAULT > R = 1 . If R = 1 , then R = 6373044 [m] , which is the mean quadratic radius.

To calculate the coordinates of the edge and of the landice interface please refer to the function sl.mhd.edge
. sl.mhd.edge
output is the natural imput for sl.mhd
. The distance employed to compute the MHD is the "great circle distance", given by sl.gc.dist
.
The MHD value in meters.
Lorenzo Zampieri
sl.mhd.edge
 MHD < (Edge1,Edge2,LandEdge1,LandEdge2,R=1)
## sl.mhd(Edge1,Edge2,LandEdge1,LandEdge2)
## Should result in double, which represent the MHD of the two edges in meters

helgegoessling/spheRlab documentation built on Sept. 29, 2017, 6:36 a.m.