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class altair.ConditionalParameterValueDefstringExprRef(param=Undefined, value=Undefined, empty=Undefined, **kwds)#

ConditionalParameterValueDefstringExprRef schema wrapper

paramstr, ParameterName

Filter using a parameter name.

valuestr, dict, ExprRef

A constant value in visual domain (e.g., "red" / "#0099ff" / gradient definition for color, values between 0 to 1 for opacity).


For selection parameters, the predicate of empty selections returns true by default. Override this behavior, by setting this property empty: false.

__init__(param=Undefined, value=Undefined, empty=Undefined, **kwds)#


__init__([param, value, empty])

copy([deep, ignore])

Return a copy of the object

from_dict(dct[, validate, _wrapper_classes])

Construct class from a dictionary representation

from_json(json_string[, validate])

Instantiate the object from a valid JSON string


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