The methods of density estimation in a stereonet.
Usage
exponential_kamb(cos_dist, sigma = 3)
linear_inverse_kamb(cos_dist, sigma = 3)
square_inverse_kamb(cos_dist, sigma = 3)
kamb_count(cos_dist, sigma = 3)
schmidt_count(cos_dist, sigma = NULL)Arguments
- cos_dist
cosine distances
- sigma
(optional) numeric. The number of standard deviations defining the expected number of standard deviations by which a random sample from a uniform distribution of points would be expected to vary from being evenly distributed across the hemisphere. This controls the size of the counting circle, and therefore the degree of smoothing. Higher sigmas will lead to more smoothing of the resulting density distribution. This parameter only applies to Kamb-based methods. Defaults to 3.
Details
exponential_kamb(): Kamb with exponential smoothing
A modified Kamb method using exponential smoothing (ref1). Units are
in numbers of standard deviations by which the density estimate
differs from uniform.
linear_inverse_kamb(): Kamb with linear smoothing
A modified Kamb method using linear smoothing (ref1). Units are in
numbers of standard deviations by which the density estimate differs from uniform.
square_inverse_kamb(): Kamb with squared smoothing
A modified Kamb method using squared smoothing (ref1). Units are in
numbers of standard deviations by which the density estimate differs from uniform.
kamb_count(): Kamb with no smoothing
Kamb's method (ref2) with no smoothing. Units are in numbers of standard
deviations by which the density estimate differs from uniform.
schmidt_count(): 1% counts. The traditional "Schmidt" (a.k.a. 1%) method.
Counts points within a counting circle comprising 1% of the total area of the
hemisphere. Does not take into account sample size. Units are in points per 1% area.
References
Vollmer, 1995. C Program for Automatic Contouring of Spherical Orientation Data Using a Modified Kamb Method. Computers & Geosciences, Vol. 21, No. 1, pp. 31–49.
Kamb, 1959. Ice Petrofabric Observations from Blue Glacier, Washington, in Relation to Theory and Experiment. Journal of Geophysical Research, Vol. 64, No. 11, pp. 1891–1909.