nhapply: Main Neighbour Apply Function
In Tobiaspk/RPackage_nhapply: Apply Functions on Cell Neighbourhoods

Description Usage Arguments

View source: R/nhapply_master.R

Apply functions on neighbourhood of pixels

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nhapply(mat, FUN, restriction = "TRUE", weights = 1, density = FALSE,
  neighb_type = 1, width = 1, include.own = FALSE, custom_neighb,
  FUN_advanced, transition = TRUE, force = FALSE)

`mat`	is an input matrix to apply a function on
`FUN`	is a function, that is applied on the neighbourhood of each point of a matrix. Optimised functions are: "mean", "sum", "max", "min", "maxCount", "maxCountValue" (which value occurs most often). It is possible to add a customised function like function(x) ... which must return a single value.
`restriction`	restricts the input matrix according to some condition as string. For example nhapply(mat, sum, restriction = "mat > 9").
`weights`	is a vector of weights that is used when summing up a neighbourhood. Vector length must be the same as points in neighbourhood.
`density`	if True, weights vector is scale to 0 - 1
`neighb_type`	specifies the type of surrounding: Type 1 is square-shaped ("Moore-Neighbourhood") Type 2 is cross-shaped ("Von-Neumann-Neighbourhood") Type 3 is diamond-shape
`width`	specifies how many neighbour pixels horizontally and vertically from center pixel should be included
`include.own`	tells, if the value of the center pixel should be included
`custom_neighb`	can be a matrix with 2 columns describing the x- and y-coordinates of the pixels to use or it can be a square matrix with odd number of rows and columns describing the neighbourhood and weights of each neighbour-pixel (0 means not using!)
`FUN_advanced`	can be used for more custom use-cases. The advanced function is applied on an open matrix where each column represents a point in a matrix and the rows its neighbourhood. Output should be a vector of same length as the number of pixels in the input matrix.
`transition`	if FALSE, matrix end at the sides, if TRUE, neighbourhood includes pixel from other side.
`force`	if your custom function outputs a different number of values than the number of points of the input matrix, force will force the program to apply the function. Do not use it, seriously, don't!