Enum vega_lite_4::StandardType
source · pub enum StandardType {
Nominal,
Ordinal,
Quantitative,
Temporal,
}
Expand description
The type of measurement ("quantitative"
, "temporal"
, "ordinal"
, or "nominal"
) for
the encoded field or constant value (datum
). It can also be a "geojson"
type for
encoding ‘geoshape’.
Vega-Lite automatically infers data types in many cases as discussed below. However, type
is required for a field if: (1) the field is not nominal and the field encoding has no
specified aggregate
(except argmin
and argmax
), bin
, scale type, custom sort
order, nor timeUnit
or (2) if you wish to use an ordinal scale for a field with bin
or timeUnit
.
Default value:
-
For a data
field
,"nominal"
is the default data type unless the field encoding hasaggregate
,channel
,bin
, scale type,sort
, ortimeUnit
that satisfies the following criteria: -"quantitative"
is the default type if (1) the encoded field containsbin
oraggregate
except"argmin"
and"argmax"
, (2) the encoding channel islatitude
orlongitude
channel or (3) if the specified scale type is a quantitative scale. -"temporal"
is the default type if (1) the encoded field containstimeUnit
or (2) the specified scale type is a time or utc scale -ordinal""
is the default type if (1) the encoded field contains a customsort
order, (2) the specified scale type is an ordinal/point/band scale, or (3) the encoding channel isorder
. -
For a constant value in data domain (
datum
): -"quantitative"
if the datum is a number -"nominal"
if the datum is a string -"temporal"
if the datum is a date time object
Note: - Data type
describes the semantics of the data rather than the primitive
data types (number, string, etc.). The same primitive data type can have different types
of measurement. For example, numeric data can represent quantitative, ordinal, or nominal
data. - Data values for a temporal field can be either a date-time string (e.g.,
"2015-03-07 12:32:17"
, "17:01"
, "2015-03-16"
. "2015"
) or a timestamp number
(e.g., 1552199579097
). - When using with
bin
, the type
property can be
either "quantitative"
(for using a linear bin scale) or "ordinal"
(for using an
ordinal bin scale). - When
using with timeUnit
, the type
property can be either "temporal"
(default, for using a temporal scale) or "ordinal"
(for using an ordinal scale).
- When using with
aggregate
, thetype
property refers to the post-aggregation data type. For example, we can calculate countdistinct
of a categorical field"cat"
using{"aggregate": "distinct", "field": "cat"}
. The"type"
of the aggregate output is"quantitative"
. - Secondary channels (e.g.,x2
,y2
,xError
,yError
) do not havetype
as they must have exactly the same type as their primary channels (e.g.,x
,y
).
See also: type
documentation.
Variants§
Trait Implementations§
source§impl Clone for StandardType
impl Clone for StandardType
source§fn clone(&self) -> StandardType
fn clone(&self) -> StandardType
1.0.0 · source§fn clone_from(&mut self, source: &Self)
fn clone_from(&mut self, source: &Self)
source
. Read more