{ "__type": "IngestedDoc", "__tag": 4010, "_content": { "Notes": { "__type": "Section", "__tag": 4015, "children": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "The ellipse equation " } ] }, { "__type": "Code", "__tag": 4050, "value": "((x * cos(alpha) + y * sin(alpha)) / x_radius) ** 2 +\n((x * sin(alpha) - y * cos(alpha)) / y_radius) ** 2 = 1", "execution_status": null }, { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Note that the positions of " }, { "__type": "InlineRole", "__tag": 4003, "value": "ellipse", "domain": null, "role": null, "inventory": null }, { "__type": "Text", "__tag": 4046, "value": " without specified " }, { "__type": "ParamRef", "__tag": 4071, "name": "shape" }, { "__type": "Text", "__tag": 4046, "value": " can have also, negative values, as this is correct on the plane. On the other hand using these ellipse positions for an image afterwards may lead to appearing on the other side of image, because " }, { "__type": "InlineCode", "__tag": 4051, "value": "image[-1, -1] = image[end-1, end-1]" } ] }, { "__type": "Code", "__tag": 4050, "value": ">>> rr, cc = ellipse(1, 2, 3, 6)\n>>> img = np.zeros((6, 12), dtype=np.uint8)\n>>> img[rr, cc] = 1\n>>> img\narray([[1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1],\n [1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1],\n [1, 1, 1, 1, 1, 1, 1, 1, 0, 1, 1, 1],\n [1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1],\n [0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0],\n [1, 1, 1, 1, 1, 1, 1, 0, 0, 0, 1, 1]], dtype=uint8)", "execution_status": null } ], "title": [], "level": 0, "target": null }, "Warns": { "__type": "Section", "__tag": 4015, "children": [], "title": [], "level": 0, "target": null }, "Raises": { "__type": "Section", "__tag": 4015, "children": [], "title": [], "level": 0, "target": null }, "Yields": { "__type": "Section", "__tag": 4015, "children": [], "title": [], "level": 0, "target": null }, "Methods": { "__type": "Section", "__tag": 4015, "children": [], "title": [], "level": 0, "target": null }, "Returns": { "__type": "Section", "__tag": 4015, "children": [ { "__type": "Parameters", "__tag": 4026, "children": [ { "__type": "DocParam", "__tag": 4016, "name": "rr, cc", "annotation": "ndarray of int", "desc": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Pixel coordinates of ellipse. May be used to directly index into an array, e.g. " }, { "__type": "InlineCode", "__tag": 4051, "value": "img[rr, cc] = 1" }, { "__type": "Text", "__tag": 4046, "value": "." } ] } ] } ] } ], "title": [], "level": 0, "target": null }, "Summary": { "__type": "Section", "__tag": 4015, "children": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Generate coordinates of pixels within ellipse." } ] } ], "title": [], "level": 0, "target": null }, "Receives": { "__type": "Section", "__tag": 4015, "children": [], "title": [], "level": 0, "target": null }, "Warnings": { "__type": "Section", "__tag": 4015, "children": [], "title": [], "level": 0, "target": null }, "Attributes": { "__type": "Section", "__tag": 4015, "children": [], "title": [], "level": 0, "target": null }, "Parameters": { "__type": "Section", "__tag": 4015, "children": [ { "__type": "Parameters", "__tag": 4026, "children": [ { "__type": "DocParam", "__tag": 4016, "name": "r, c", "annotation": "double", "desc": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Centre coordinate of ellipse." } ] } ] }, { "__type": "DocParam", "__tag": 4016, "name": "r_radius, c_radius", "annotation": "double", "desc": [ { "__type": "Paragraph", "__tag": 4045, "children": [ { "__type": "Text", "__tag": 4046, "value": "Minor and major semi-axes. 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