weibullFit {WeibullFit}

Weibull-fitting function

Description

This functions calculates the shape, scale and location parameters for the weibull distribution to the input data and save the plots.

Usage

weibullFit(dataFrame, primaryGroup = "parcela",
  secondaryGroup = "idadearred", restrValue, pValue = "dap",
  leftTrunc = 5, folder = NA, limit = 1e+05,
  selectedFunctions = NULL, amp = 2, pmaxIT = 20, verbose = FALSE)

Arguments

dataFrame

the input data frame containing the independent, continuous variable.

primaryGroup

the name(String) of the primary grouping column of the data frame.

secondaryGroup

the name(String) of the secondary grouping column of the data frame.

restrValue

the restriction value choosen to be applied to the secondary group column.

pValue

the name(String) of the independent, continuos variable to be analyzed.

leftTrunc

An integer, defining the value for the weibull's function truncation.

folder

the pathname of the folder where the plots will be saved.

limit

A positive integer determining the maximum number of rows from the data frame (grouped by the primary group column) to be analyzed.

selectedFunctions

A character vector determining which weibull function to be applied. Can be any of the following: w2, w2te, w2td, w2tetd, w3, w3te, w3td, w3tetd

amp

The continuous variable class width to be accounted for the calculations.

pmaxIT

A positive integer, the maximum number of iterations used by the algorithm to try to get the weibull function parameters, for each primary group.

verbose

Logical, determines if the function prints more detailed results on the console.

Details

This function first extracts a subset of the input data frame using the restrValue parameter applied to the secondary group column. Then, it calculates the weibull function scale, shape and location parameters using the maximum-likelyhood method. Finally, it plots the results (as .wmf, .csv and .jpeg) inside the folder given by the Folder parameter.

Value

A data frame object containing the best results for shape, location and scale parameters.

Examples

functions <- c("w2", "w3")
best <- weibullFit(restrValue = 60, dataFrame = TreesDBH,
selectedFunctions = functions, amp = 2, pmaxIT = 1, limit = 1)