simulation.utils.urdf.core module

Class definitions of core building blocks of the package.

Summary

Classes:

Attribute	Basic class that will be converted into a xml attribute.
Axis
Origin
XmlObject	Base class for all urdf xml objects.

Reference

class Attribute(val: str, name: Optional[str] = None)

Bases: str

Basic class that will be converted into a xml attribute.

Important: Within a subclass of XmlObject an attribute can be defined by simply annotating a class variable with py:class:Attribute!

Example

>>> from dataclasses import dataclass
>>> from urdf.core import XmlObject, Attribute
>>> @dataclass
... class Example(XmlObject):
...     TAG = "example"
...     name: Attribute
...     value1: str
...     value2: float = None
>>> ex = Example("example_name",value1="I'm an example.")

The code block defines a simple example class that results in the xml string:

<example name="example_name">
  <value1>I'm an example.</value1>
</example>

Parameters

• val – Attribute value.

• name – Optionally the name of the can be provided. By default the name of the Attribute instance defines the name of the resulting xml attribute.

class XmlObject

Bases: object

Base class for all urdf xml objects.

TAG = None

_get_val(val: Any) → str

Convert a value to a string that is included into the xml.

create_xml(root_el: Optional[xml.etree.ElementTree.Element] = None) → xml.etree.ElementTree.Element

Convert this instance into a xml element.

• If the class of this instance does not define a tag, new xml elements from this instance are appended to the root_el. Otherwise, a sub element is created and returned.

• Additionally to all instance attributes, a dictionary parameters can be used to define sub elements.

• A Attribute type annotation for any of the object`s attributes, will result in a xml attribute.

Parameters

root_el – Optional element that is used a parent xml element when provided.

save(file_path: str)

Save this instance as a xml string to a file.

Parameters

file_path – Location to store the xml.

_origin_default_list()

class Origin(xyz: simulation.utils.urdf.core.Attribute = <factory>, rpy: simulation.utils.urdf.core.Attribute = <factory>)

Bases: simulation.utils.urdf.core.XmlObject

TAG = 'origin'

xyz: simulation.utils.urdf.core.Attribute

rpy: simulation.utils.urdf.core.Attribute

classmethod from_vector(vector: simulation.utils.geometry.vector.Vector)

classmethod from_list(lst: List[float])

class Axis(xyz: simulation.utils.urdf.core.Attribute = <factory>)

Bases: simulation.utils.urdf.core.XmlObject

TAG = 'axis'

xyz: simulation.utils.urdf.core.Attribute