stat.kurt: Measure kurtosis from cumulative distribution data

In dtavern/grainsizeR: Extract And Analyze Grain Size Distributions

Description

Measure kurtosis from cumulative distribution data

Usage

stat.kurt(sieve_size, cumu, units = "phi", method = "all")

Arguments

sieve_size	vector of sieve sizes related to input cumulative distribution
cumu	cumulative distribution pertaining to sieve sizes
units	sieve size units "phi" = phi scale, "mm" = milimeter scale
method	Method to calculate kurtosis. Arithmetic methods: "fw" = Folk and Ward, 1957. This method is typically used for phi units and is fairly standard; "inm" = Inman, 1952. For phi scale and focuses on tails of distribution; "tra" = Trask, 1932. For metric (mm) data. Geometric methods: "sqrt" = Square root method for geometric approach in metric units;"log" = log transform metric data. Geometric approach. "all" = compute all methods into a data frame.

Value

a numeric value or dataframe according to method chosen

Source

see Bunte and Abt (2001) for examples and equations. Bunte, Kristin, and Steven R. Abt. "Sampling surface and subsurface particle-size distributions in wadable gravel-and cobble-bed streams for analyses in sediment transport, hydraulics, and streambed monitoring." (2001).

dtavern/grainsizeR documentation built on May 15, 2019, 4:53 p.m.