Asserts if the given input matrix is a (discrete) survival probabilities matrix using Rcpp code. The following checks are performed:

All values are probabilities, i.e. \(S(t) \in [0,1]\)

Column names correspond to time-points and should therefore be coercable to

`numeric`

and increasingPer row/observation, the survival probabilities decrease non-strictly, i.e. \(S(t) \ge S(t+1)\)

## Arguments

- x
(

`matrix()`

)

A matrix of (predicted) survival probabilities. Rows are observations, columns are (increasing) time points.