Operators acting on trajectories to extract or replace parts.

# S3 method for trajectory
[(x, i)
# S3 method for trajectory
[[(x, i)
# S3 method for trajectory
[(x, i) <- value
# S3 method for trajectory
[[(x, i) <- value

## Arguments

x |
the trajectory object. |

i |
indices specifying elements to extract. Indices are `numeric` or `character`
or `logical` vectors or empty (missing) or `NULL` .
Numeric values are coerced to integer as by `as.integer` (and hence truncated towards
zero). Negative integers indicate elemets/slices to leave out the selection.
Character vectors will be matched to the names of the activities in the trajectory as by
`%in%` .
Logical vectors indicate elements/slices to select. Such vectors are recycled if necessary to
match the corresponding extent.
An empty index will return the whole trajectory.
An index value of `NULL` is treated as if it were `integer(0)` . |

value |
another trajectory object. |

## Value

Returns a new trajectory object.

## See also

`length.trajectory`

, `get_n_activities`

, `join`

.