sim.data {denpro} R Documentation

## Generates data for illustrative purposes

### Description

Returns a random sample from some distributions, to illustrate some visulization tools. Returns also the density (as a piecewise constant function) for some examples, or the distribution function.

### Usage

```sim.data(n = NULL, seed = 1, N = NULL, type = "mulmod",
M = NULL, sig = NULL, p = NULL, d = NULL,
cova = NULL, marginal = NULL, t = NULL, df = NULL, distr = FALSE,
noisedim = 1, sig1 = 0.5, sig2 = 1.5, diff = 0.1, dist = 4)
```

### Arguments

 `n` positive integer; size of the sample to be generated `seed` real number; seed for the random number generator. `N` 2*1 vector of positive integers; the size of the grid where the piecewise constant function is evaluated `type` "mixt", "mulmod", "fox", "tetra3d", "penta4d", "cross", "gauss", "student", "gumbel", "1d2modal", or "claw". `M` mixnum*d-matrix; rows of M are means of the Gaussians in the mixture. We have a mixture of "mixnum" Gaussians, whose dimension is d. `sig` mixnum*d-matrix; rows of sig are the diagonals of the covariance matrices of the mixtures. `p` mixnum-vector; weights for the members of the mixture. The sum of elements of "p" is 1. `d` positive integer; dimension of the vectors of the sample to be generated, need to be given only when type="mixt" and d=1 `cova` Covariance matrix for the Gauss or Student copulas `marginal` NULL, "gauss", or "student"; this parameter is used to give the marginal distribution for the Gauss or Student copulas; if marginal=NULL, then the uniform marginals are used `t` if marginal="student", gives the degrees of freedom `df` degrees of freedom for the Student copula `distr` internal (implemented for "1d2modal") TRUE, if one wants the distribution function instead of the density function `noisedim` the number of noise dimension in the projection pursuit example ("fssk") `sig1` standard deviation for "cross" and "diff1d" `sig2` second standard deviation for "cross" `diff` parameter for "diff1d"; the difference between the Gaussians in the 1D mixture `dist` a positive real number; gives the distance between the mixture centers in the 4D mixture of Gaussians "penta4d"

### Details

When type="mixt", generates data from a mixture of Gaussians. When type="mulmod", the density is 3-modal. When type="fox", the density has multimodal level sets.

### Value

If "n" is not NULL, then the function returns a n*d-data matrix or a n*2-data matrix, if "N" is not NULL, then the function returns a piecewise constant function on the grid of size N[1]*N[2], if the both are NULL, then the function returns the mean, covariance, and the weights of the mixture components

Jussi Klemela

### Examples

```d<-2
mixnum<-3
M<-matrix(0,mixnum,d)
M[1,]<-c(0,0)
M[2,]<-c(4,0)
M[3,]<-c(0,4)
sig<-matrix(1,mixnum,d)
p0<-1/mixnum
p<-p0*rep(1,mixnum)
n<-100
dendat<-sim.data(type="mixt",n=n,M=M,sig=sig,p=p,seed=1)
plot(dendat)

dendat<-sim.data(n=100)
plot(dendat)

N<-c(20,20)
pcf<-sim.data(N=N)
dp<-draw.pcf(pcf,pnum=c(30,30))
contour(dp\$x,dp\$y,dp\$z,drawlabels=FALSE)

sim.data()

type="fox"
dendat<-sim.data(n=100,type=type)
plot(dendat)

pcf<-sim.data(N=N,type=type)
dp<-draw.pcf(pcf,pnum=c(30,30))
contour(dp\$x,dp\$y,dp\$z,drawlabels=FALSE)

```

[Package denpro version 0.9.0 Index]