Slice¶
Extract a range/slice of elements from a column of texts or lists.
Using start
, stop
and step
to define a range of indices, the corresponding range of elements is extracted
from each text or list in the input column.
Note: indices start at 0, and a stop
of 3 means elements up to but not including the element at index 3
will be extracted. In particular this means simply specifying "stop": 3
(setting or leaving start
at its
default of 0), will extract 3 elements in total.
Usage¶
The following are the step's expected inputs and outputs and their specific types.
slice(input: text|list, {"param": value}) -> (output: column)
where the object {"param": value}
is optional in most cases and if present may contain any of the parameters described in the
corresponding section below.
Inputs¶
input: column:text|list
A column containing texts or lists to extract a range of characters or elements from.
Outputs¶
output: column
Contains the extracted slices. The type depends on the out_type
parameter, and needs to be consistent with the transformation.
Parameters¶
start: integer | null
Index of the first element to be extracted from each string or list in the input column.
stop: integer | null
Index at which to stop including elements from the list. The element at the stop
index will not be included. As an example, "start": 0, "stop": 3
will include all elements up to but not including the element at index 3, thus extracting a
total of 3 elements.
step: integer | null = 1
Step size used to move from start
to stop
index. E.g., if "step": 2
, only every second element from the range [start
, stop
] is returned.
out_type: string
Select types using their name.
Must be one of:
"category"
,
"date"
,
"number"
,
"boolean"
,
"url"
,
"sex"
,
"text"
,
"list[number]"
,
"list[category]"
,
"list[url]"
,
"list[boolean]"
,
"list[date]"