{
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  "_content": {
    "Notes": {
      "__type": "Section",
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      "children": [
        {
          "__type": "Paragraph",
          "__tag": 4045,
          "children": [
            {
              "__type": "Text",
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              "value": "Wu's method draws anti-aliased circle. This implementation doesn't use lookup table optimization."
            }
          ]
        },
        {
          "__type": "Paragraph",
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          "children": [
            {
              "__type": "Text",
              "__tag": 4046,
              "value": "Use the function "
            },
            {
              "__type": "InlineCode",
              "__tag": 4051,
              "value": "draw.set_color"
            },
            {
              "__type": "Text",
              "__tag": 4046,
              "value": " to apply "
            },
            {
              "__type": "InlineCode",
              "__tag": 4051,
              "value": "circle_perimeter_aa"
            },
            {
              "__type": "Text",
              "__tag": 4046,
              "value": " results to color images."
            }
          ]
        }
      ],
      "title": [],
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    "Warns": {
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    },
    "Raises": {
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    "Yields": {
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    },
    "Methods": {
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    },
    "Returns": {
      "__type": "Section",
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      "children": [
        {
          "__type": "Parameters",
          "__tag": 4026,
          "children": [
            {
              "__type": "DocParam",
              "__tag": 4016,
              "name": "rr, cc, val",
              "annotation": "(N,) ndarray (int, int, float)",
              "desc": [
                {
                  "__type": "Paragraph",
                  "__tag": 4045,
                  "children": [
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": "Indices of pixels ("
                    },
                    {
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                      "__tag": 4002,
                      "value": "rr",
                      "reference": {
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                        "__tag": 4000,
                        "module": null,
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                        "kind": "local",
                        "path": "rr"
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                      "value": ", "
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                    {
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                      "value": "cc",
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                    {
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                      "value": ") and intensity values ("
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                    {
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                      "value": "). "
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                      "value": "img[rr, cc] = val"
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    "Summary": {
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      "children": [
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          "__type": "Paragraph",
          "__tag": 4045,
          "children": [
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              "value": "Generate anti-aliased circle perimeter coordinates."
            }
          ]
        }
      ],
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      "level": 0,
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    },
    "Receives": {
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    },
    "Attributes": {
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    "Parameters": {
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              "name": "r, c",
              "annotation": "int",
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                  "children": [
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                      "value": "Centre coordinate of circle."
                    }
                  ]
                }
              ]
            },
            {
              "__type": "DocParam",
              "__tag": 4016,
              "name": "radius",
              "annotation": "int",
              "desc": [
                {
                  "__type": "Paragraph",
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                  "children": [
                    {
                      "__type": "Text",
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                      "value": "Radius of circle."
                    }
                  ]
                }
              ]
            },
            {
              "__type": "DocParam",
              "__tag": 4016,
              "name": "shape",
              "annotation": "tuple, optional",
              "desc": [
                {
                  "__type": "Paragraph",
                  "__tag": 4045,
                  "children": [
                    {
                      "__type": "Text",
                      "__tag": 4046,
                      "value": "Image shape which is used to determine the maximum extent of output pixel coordinates. This is useful for circles that exceed the image size. If None, the full extent of the circle is used.  Must be at least length 2. Only the first two values are used to determine the extent of the input image."
                    }
                  ]
                }
              ]
            }
          ]
        }
      ],
      "title": [],
      "level": 0,
      "target": null
    },
    "Extended Summary": {
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    },
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    }
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    "Methods",
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    "Warnings"
  ],
  "item_file": "/dev/scikit-image/src/skimage/draw/draw.py",
  "item_line": 585,
  "item_type": "function",
  "aliases": [
    "skimage.draw.circle_perimeter_aa"
  ],
  "example_section_data": {
    "__type": "Section",
    "__tag": 4015,
    "children": [
      {
        "__type": "Code",
        "__tag": 4050,
        "value": "from skimage.draw import circle_perimeter_aa\nimg = np.zeros((10, 10), dtype=np.uint8)\nrr, cc, val = circle_perimeter_aa(4, 4, 3)\nimg[rr, cc] = val * 255\nimg\n",
        "execution_status": "success"
      },
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        "__type": "Text",
        "__tag": 4046,
        "value": "\n"
      },
      {
        "__type": "Code",
        "__tag": 4050,
        "value": "from skimage import data, draw\nimage = data.chelsea()\nrr, cc, val = draw.circle_perimeter_aa(r=100, c=100, radius=75)\ndraw.set_color(image, (rr, cc), [1, 0, 0], alpha=val)\n",
        "execution_status": "success"
      }
    ],
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    "target": null
  },
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        "annotation": {
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        },
        "kind": "POSITIONAL_OR_KEYWORD",
        "default": {
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        }
      },
      {
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        "name": "c",
        "annotation": {
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        },
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        "default": {
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        }
      },
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        "name": "radius",
        "annotation": {
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        },
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        }
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      {
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        "default": "None"
      }
    ],
    "return_annotation": {
      "__type": "Empty",
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    },
    "target_name": "circle_perimeter_aa"
  },
  "references": [
    ".. [1] X. Wu, \"An efficient antialiasing technique\", In ACM SIGGRAPH",
    "       Computer Graphics, 25 (1991) 143-152."
  ],
  "qa": "skimage.draw.draw:circle_perimeter_aa",
  "arbitrary": [],
  "local_refs": [
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}