ecol.death.sim {animation} R Documentation

## A simulation of the death of two species with certain probabilities

### Description

Suppose there are two plant species in a field: A and B. One of them will die at each time and a new plant will grow in the place where the old plant died; the species of the new plant depends on the proportions of two species: the larger the proportion is, the greater the probability for this species to come up will be.

### Usage

```ecol.death.sim(nr = 10, nc = 10, num.sp = c(50, 50), col.sp = c(1, 2), pch.sp = c(1,
2), col.die = 1, pch.die = 4, cex = 3, ...)
```

### Arguments

 `nr, nc` number of rows and columns of the field (plants grow on a `nr` x `nc` grid) `num.sp` number of two plants respectively `col.sp, pch.sp` colors and point symbols of the two species respectively `col.die, pch.die, cex` the color, point symbol and magnification to annotate the plant which dies (symbol default to be an ‘X’) `...` other arguments passed to `plot` to set up the plot

### Value

a vector (factor) containing 1's and 2's, denoting the plants finally survived

### Note

`2 * ani.options('nmax')` image frames will actually be produced.

Yihui Xie

### References

This animation is motivated by a question raised from Jing Jiao, a student in biology, to show the evolution of two species.

The original post is in the forum of the “Capital of Statistics”: http://cos.name/cn/topic/14093 (in Chinese)

### Examples

```
oopt = ani.options(nmax = ifelse(interactive(), 50, 2), interval = 0.3)
par(ann = FALSE, mar = rep(0, 4))
ecol.death.sim()

## large scale simulation
ani.options(nmax = ifelse(interactive(), 1000, 2), interval = 0.02)
ecol.death.sim(col.sp = c(8, 2), pch.sp = c(20, 17))

ani.options(oopt)

```

[Package animation version 2.5 Index]