# snntsmarginallongitude: Marginal density function for the longitude of the SNNTS... In CircNNTSR: Statistical Analysis of Circular Data using Nonnegative Trigonometric Sums (NNTS) Models

## Description

Marginal density function for the longitude of the SNNTS model for spherical data

## Usage

 `1` ```snntsmarginallongitude(data, cpars = 1, M = c(0,0)) ```

## Arguments

 `data` Vector of angles in radians, with one row for each data point. The data must be between zero and 2*pi `cpars` Vector of complex numbers of dimension prod(M+1). The first element is a real and positive number. The first M+1 elements correspond to longitude, and the next M+1 elements correspond to latitude. The sum of the squared moduli of the c parameters must be equal to one. `M` Vector with number of components in the SNNTS for each dimension

## Value

The function returns the density function evaluated for the data

## Note

The parameters cpars used by this function are the transformed parameters of the SNNTS density function, which lie on the surface of the unit hypersphere

## Author(s)

Juan Jose Fernandez-Duran and Maria Mercedes Gregorio-Dominguez

## References

Fernandez-Duran J. J. y Gregorio Dominguez, M. M. (2008) Spherical Distributions Based on Nonnegative Trigonometric Sums, Working Paper, Statistics Department, ITAM, DE-C08.6

## Examples

 ```1 2 3 4 5 6 7``` ``` set.seed(200) data(Datab6fisher_ready) data<-Datab6fisher_ready M<-c(1,2) cest<-snntsmanifoldnewtonestimation(data, M,iter=150) long<-snntsmarginallongitude(seq(0,2*pi,.1),cest\$cestimates[,3],M) plot(seq(0,2*pi,.1),long,type="l") ```

CircNNTSR documentation built on Feb. 18, 2020, 9:15 a.m.