CalculatePopChange {capm} | R Documentation |

## Population change.

### Description

Calculate the change in population size between two times. When only one time is specified, the population size at that time is returned.

### Usage

```
CalculatePopChange(model.out = NULL, variable = NULL, t1 = NULL,
t2 = NULL, ratio = TRUE)
```

### Arguments

`model.out` |
output from one of the following functions or a |

`variable` |
string with the name of the the output variable for which the change are to be calculated (see the variable argument for |

`t1` |
value specifying the first time. |

`t2` |
value specifying the second time. |

`ratio` |
logical. When |

### Value

Value representing the ratio (if `ratio`

is `TRUE`

) or the difference (if `ratio`

is `FALSE`

) between population size at time t2 and t1. If only one time is specified, the value is the population size at that time.

### References

Baquero, O. S., Marconcin, S., Rocha, A., & Garcia, R. D. C. M. (2018). Companion animal demography and population management in Pinhais, Brazil. Preventive Veterinary Medicine.

http://oswaldosantos.github.io/capm

### Examples

```
## IASA model
## Parameters and intial conditions.
data(dogs)
dogs_iasa <- GetDataIASA(dogs,
destination.label = "Pinhais",
total.estimate = 50444)
# Solve for point estimates.
solve_iasa_pt <- SolveIASA(pars = dogs_iasa$pars,
init = dogs_iasa$init,
time = 0:15,
alpha.owned = TRUE,
method = 'rk4')
# Calculate the population change (ratio) between times 0 and 15.
CalculatePopChange(solve_iasa_pt, variable = 'N1', t2 = 15, t1 = 0)
# Calculate the population change (difference) between times 0 and 15.
CalculatePopChange(solve_iasa_pt, variable = 'N1', t2 = 15,
t1 = 0, ratio = FALSE)
# Calculate the population zises at time 15.
CalculatePopChange(solve_iasa_pt, variable = 'N1', t2 = 15)
```

*capm*version 0.14.0 Index]