altair.TopoDataFormat#
- class altair.TopoDataFormat(feature=Undefined, mesh=Undefined, parse=Undefined, type=Undefined, **kwds)#
TopoDataFormat schema wrapper.
- Parameters:
- featurestr
The name of the TopoJSON object set to convert to a GeoJSON feature collection. For example, in a map of the world, there may be an object set named
"countries"
. Using the feature property, we can extract this set and generate a GeoJSON feature object for each country.- meshstr
The name of the TopoJSON object set to convert to mesh. Similar to the
feature
option,mesh
extracts a named TopoJSON object set. Unlike thefeature
option, the corresponding geo data is returned as a single, unified mesh instance, not as individual GeoJSON features. Extracting a mesh is useful for more efficiently drawing borders or other geographic elements that you do not need to associate with specific regions such as individual countries, states or counties.- parsedict, None,
Parse
If set to
null
, disable type inference based on the spec and only use type inference based on the data. Alternatively, a parsing directive object can be provided for explicit data types. Each property of the object corresponds to a field name, and the value to the desired data type (one of"number"
,"boolean"
,"date"
, or null (do not parse the field)). For example,"parse": {"modified_on": "date"}
parses themodified_on
field in each input record a Date value.For
"date"
, we parse data based using JavaScript’s Date.parse(). For Specific date formats can be provided (e.g.,{foo: "date:'%m%d%Y'"}
), using the d3-time-format syntax. UTC date format parsing is supported similarly (e.g.,{foo: "utc:'%m%d%Y'"}
). See more about UTC time- typeLiteral[‘topojson’]
Type of input data:
"json"
,"csv"
,"tsv"
,"dsv"
.Default value: The default format type is determined by the extension of the file URL. If no extension is detected,
"json"
will be used by default.
- __init__(feature=Undefined, mesh=Undefined, parse=Undefined, type=Undefined, **kwds)#
Methods
__init__
([feature, mesh, parse, type])copy
([deep, ignore])Return a copy of the object.
from_dict
(dct[, validate])Construct class from a dictionary representation.
from_json
(json_string[, validate])Instantiate the object from a valid JSON string.
resolve_references
([schema])Resolve references in the context of this object's schema or root schema.
to_dict
([validate, ignore, context])Return a dictionary representation of the object.
to_json
([validate, indent, sort_keys, ...])Emit the JSON representation for this object as a string.
validate
(instance[, schema])Validate the instance against the class schema in the context of the rootschema.
validate_property
(name, value[, schema])Validate a property against property schema in the context of the rootschema.