# dsimpriorppt: Prior projected Polya tree distribution In PPTcirc: Projected Polya Tree for Circular Data

## Description

Simulates paths of prior projected Polya tree distributions centered around a projected normal distribution.

## Usage

 ```1 2``` ```dsimpriorppt(nsim = 5, mm = 4,mu = c(0, 0), sig = 1, ll = 100, aa = 1, delta = 1.1, units = "radians") ```

## Arguments

 `nsim` integer indicating the number of simulations. `mm` integer indicating the number of finite levels of the Polya tree. `mu` mean vector of the projected bivariate normal distribution. `sig` standard deviation of the projected bivariate normal distribution. We advise to always use sig = 1. `ll` number of equally spaced points at which the projected distribution will be evaluated. `aa` alpha. Precision parameter of the Polya tree. `delta` controls of the speed at which the variances of the branching probabilities move down in the tree, rho(m)=m^delta. `units` units of the support: "radians", "degrees" or "hours".

## Value

An object with class priorppt.circ whose underlying structure is a list containing the following components:

 `x` points where the density is evaluated. `ppt.sims` simulated density paths of the prior projected Polya tree. `stats` descriptive statistics: mean direction and concentration of each simulated density.

## References

Nieto-Barajas, L.E. & Nunez-Antonio, G. (2019). Projected Polya tree. https://arxiv.org/pdf/1902.06020.pdf

`priorppt.plot`, `priorppt.summary`
 ```1 2 3``` ```z <- dsimpriorppt(mu = c(5,5), nsim = 5, units = "radians") priorppt.plot(z, plot.type = "line") summary(z\$stats) ```