These are the currently available `evaluator`

-functions for `tfd`

-objects,
which control how the entries are inter-/extrapolated to previously unseen
`arg`

-values. They all are merely wrappers around `zoo::na.fill()`

,
`zoo::na.approx()`

, etc... Note that these are not meant to be called directly --
they are internal functions used by `tf_evaluate.tfd()`

to do its thing.

The list:

`tf_approx_linear`

for linear interpolation without extrapolation (i.e.,
`zoo::na.approx()`

with `na.rm = FALSE`

) -- this is the default,

`tf_approx_spline`

for cubic spline interpolation, (i.e., `zoo::na.spline()`

with `na.rm = FALSE`

),

`tf_approx_none`

in order to not inter-/extrapolate ever (i.e., `zoo::na.fill()`

with `fill = NA`

)

`tf_approx_fill_extend`

for linear interpolation and constant extrapolation
(i.e., `zoo::na.fill()`

with `fill = "extend"`

)

`tf_approx_locf`

for "last observation carried forward" (i.e.,
`zoo::na.locf()`

with `na.rm = FALSE`

and

`tf_approx_nocb`

for "next observation carried backward" (i.e.,
`zoo::na.locf()`

with `na.rm = FALSE, fromLast = TRUE`

).

For implementing your own, see source code of `tidyfun:::zoo_wrapper`

.

tf_approx_linear(x, arg, evaluations)
tf_approx_spline(x, arg, evaluations)
tf_approx_none(x, arg, evaluations)
tf_approx_fill_extend(x, arg, evaluations)
tf_approx_locf(x, arg, evaluations)
tf_approx_nocb(x, arg, evaluations)

## Arguments

x |
new arg values to tf_approximate the function for |

arg |
the `arg` values of the `evaluations` |

evaluations |
the function's values at `arg` |

## See also