# piecewise_xy

From IBMPopSim v0.3.0
by Daphnc3 Giorgi

##### Piecewise real function of two variables.

Given the vectors `(breaks[1],...,breaks[n])`

and the list of `IBMPopSim`

compatible
functions `funs = (f[0],f[1],...,f[n])`

(one value more!), `piecewise_xy(breaks, funs)`

returns
the function
$$f(x,y) = f_0(x) {1}_{y\le breaks[1]}+\sum_{k=1}^{n-1} f_k(x) {1}_{[breaks_{k}, breaks_{k+1})}(y) + f_n(x){1}_{y \ge breaks[n]}$$

##### Usage

`piecewise_xy(breaks, funs)`

##### Arguments

- breaks
Numeric vector giving the breaks of functions given in

`funs`

. Must be sorted with unique values.- funs
List of functions.

##### Details

A C++ version of this function is available. See `vignette('IBMPopSim_cpp')`

for more details.

##### Value

Piecewise bivariate function built with the given intervals and functions.

##### Examples

```
# NOT RUN {
time_dep_function <- piecewise_xy(c(5),
list(gompertz(0.1, 0.005), gompertz(0.08, 0.005)))
time_dep_function(0, 65) # death intensity at time 0 and age 65.
# }
```

*Documentation reproduced from package IBMPopSim, version 0.3.0, License: MIT + file LICENSE*

### Community examples

Looks like there are no examples yet.