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By default, it is False and the scalar-last order is used." } ] }, { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "The mapping from quaternions to rotations is two-to-one, i.e. quaternions " }, { "__type": "InlineCode", "__tag": 4051, "value": "q" }, { "__type": "Text", "__tag": 4046, "value": " and " }, { "__type": "InlineCode", "__tag": 4051, "value": "-q" }, { "__type": "Text", "__tag": 4046, "value": ", where " }, { "__type": "InlineCode", "__tag": 4051, "value": "-q" }, { "__type": "Text", "__tag": 4046, "value": " simply reverses the sign of each component, represent the same spatial rotation." } ] } ], "title": [], "level": 0, "target": null }, "Other Parameters": { "__type": "Section", "__tag": 4015, "children": [], "title": [], "level": 0, "target": null } }, "_ordered_sections": [ "Summary", "Extended Summary", "Parameters", "Attributes", "Methods", "Returns", "Yields", "Receives", "Other Parameters", "Raises", "Warns", "Warnings", "Notes" ], "item_file": "/scipy/spatial/transform/_rotation.py", "item_line": 961, "item_type": "function", "aliases": [ "scipy.spatial.transform.Rotation.as_quat" ], "example_section_data": { "__type": "Section", "__tag": 4015, "children": [ { "__type": "Code", "__tag": 4050, "value": "from scipy.spatial.transform import Rotation as R\nimport numpy as np\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\nA rotation can be represented as a quaternion with either scalar-last\n(default) or scalar-first component order.\nThis is shown for a single rotation:\n\n" }, { "__type": "Code", "__tag": 4050, "value": "r = R.from_matrix(np.eye(3))\nr.as_quat()\nr.as_quat(scalar_first=True)\n", "execution_status": "success" }, { "__type": "Text", "__tag": 4046, "value": "\nThe resulting shape of the quaternion is always the shape of the Rotation\nobject with an added last dimension of size 4. 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