# as_surv()


Convert an event-time vector to a [Surv](Surv.md#greenwood.Surv) response.


Usage

``` python
as_surv(x)
```


The type of the result depends on the status codes present, ignoring missing elements:

- only `"e"` and `"r"`: a right-censored response, with status `1` for events.
- only `"e"` and `"l"`: a left-censored response, with status `1` for events.
- any other combination: an interval response, with R's codes `0` (right), `1` (exact), `2` (left), and `3` (interval).

Missing elements are missing in the result.


## Parameters


`x: Any`  
An [EventTime](EventTime.md#greenwood.EventTime) vector.


## Returns


`Surv`  
The response.


## Raises


`TypeError`  
If `x` isn't an [EventTime](EventTime.md#greenwood.EventTime) vector.


## Examples


``` python
import greenwood as gw

x = gw.event_time(
    time=[7, 5, 3, 2],
    status=["e", "r", "l", "i"],
    time_max=[None, None, None, 4],
)
gw.as_surv(x).to_frame(format="polars")
```


shape: (4, 3)

| time1 | time2 | status |
|-------|-------|--------|
| f64   | f64   | f64    |
| 7.0   | 1.0   | 1.0    |
| 5.0   | 1.0   | 0.0    |
| 3.0   | 1.0   | 2.0    |
| 2.0   | 4.0   | 3.0    |


Exact and right-censored values give a right-censored response:


``` python
gw.as_surv(gw.event_time(time=[7, 5], status=["e", "r"]))
```


    Surv(type=right, n=2, events=1)