{"id":591,"date":"2023-02-06T13:13:27","date_gmt":"2023-02-06T05:13:27","guid":{"rendered":"http:\/\/39.104.58.144\/?page_id=591"},"modified":"2023-02-15T09:26:27","modified_gmt":"2023-02-15T01:26:27","slug":"projective-variance-split","status":"publish","type":"page","link":"http:\/\/www.algmain.com\/index.php\/algorithm-article\/projective-variance-split\/","title":{"rendered":"\u6295\u5f71\u65b9\u5dee\u5206\u5272"},"content":{"rendered":"\n

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\n

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Kd\u6811\u7b97\u6cd5<\/h2>\n\n\n\n

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\"\"
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\n

AlgMain : \u4e00\u7ef4\u6295\u5f71\u65b9\u5dee\u5206\u5272<\/a>
AlgMain : \u4e8c\u7ef4\u6295\u5f71\u65b9\u5dee\u5206\u5272<\/a>
AlgMain : \u4e09\u7ef4\u6295\u5f71\u65b9\u5dee\u5206\u5272<\/a>
AlgMain : \u591a\u7ef4\u6295\u5f71\u65b9\u5dee\u5206\u5272<\/a><\/p>\n<\/blockquote>\n\n\n\n

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\u6295\u5f71\u65b9\u5dee\u5206\u5272\u7684\u7279\u70b9<\/h2>\n\n\n\n

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    \n
  • \u5e73\u79fb\u4e0d\u53d8\u6027<\/li>\n\n\n\n
  • \u65cb\u8f6c\u4e0d\u53d8\u6027<\/li>\n\n\n\n
  • \u7f29\u653e\u4e0d\u53d8\u6027<\/li>\n<\/ul>\n\n\n\n

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    \u6295\u5f71\u65b9\u5dee\u5206\u5272\u7684\u4f8b\u5b50<\/h2>\n\n\n\n

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    \"\"
    \u56fe4 \u4e8c\u7ef4\u70b9\u7fa4\u65b9\u5dee\u5206\u5272<\/figcaption><\/figure>\n\n\n\n

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    \"\"
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    \"\"
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    \u53c2\u8003\u4ee3\u7801(Matlab)<\/h2>\n\n\n
    \nfunction [xMean,yMean,beta,deviation] = MinVarianceSplit(xValues,yValues)\n    %\u9884\u5904\u7406\u68c0\u6d4b\n    count = length(xValues);\n    if count <= 0\n        fprintf('\u8f93\u5165\u7684\u6570\u7ec4\u6ca1\u6709\u5143\u7d20\uff01\\n');\n        return;\n    end\n    if count ~= length(yValues)\n        fprintf('\u8f93\u5165\u7684X\uff0cY\u6570\u7ec4\u957f\u5ea6\u4e0d\u4e00\u81f4\uff01\\n');\n        return;\n    end\n    %\u6c42X\uff0cY\u5e73\u5747\u503c\n    xMean = mean(xValues);\n    yMean = mean(yValues);\n    %\u5e73\u79fb\u6240\u6709\u70b9\u81f3\u4e2d\u5fc3\u70b9\u4f4d\u7f6e\n    xNewValues = xValues - xMean;\n    yNewValues = yValues - yMean;\n    %\u8ba1\u7b97\u51e0\u4e2a\u5e38\u7528\u6570\u503c\n    xyNewValue = xNewValues * yNewValues';\n    xxNewValue = xNewValues * xNewValues';\n    yyNewValue = yNewValues * yNewValues';\n    %\u8ba1\u7b97beta\u89d2\u5ea6\n    beta = atan(2 * xyNewValue \/ (xxNewValue - yyNewValue)) \/ 2;\n    %\u8ba1\u7b97\u4e8c\u9636\u5bfc\u6570\u5224\u522b\u5f0f\n    delta = - 2 * (xyNewValue * sin(2 * beta) + (xxNewValue - yyNewValue) * cos(2 * beta));\n    %\u68c0\u67e5\u5224\u522b\u5f0f\n    if delta < 0\n        %\u4e8c\u9636\u5bfc\u6570\u5c0f\u4e8e\u96f6\uff0c\u8bf4\u660e\u662f\u6781\u5927\u503c\n        %\u53e6\u5916\u4e00\u4e2a\u5782\u76f4\u65b9\u5411\u5c31\u662f\u6781\u5c0f\u503c\u65b9\u5411\n        beta = beta + pi \/ 2.0;\n    end\n    %\u68c0\u67e5\u8ba1\u7b97\u7ed3\u679c\n    %\u8c03\u6574\u8f93\u51fa\u65b9\u5411\u5728\uff080,pi\uff09\u533a\u95f4\u5185\n    if beta < 0\n        beta = beta + pi;\n    elseif beta > pi\n        beta = beta - pi;\n    end\n    %\u8ba1\u7b97\u6295\u5f71\u70b9\u4e4b\u95f4\u7684\u65b9\u5dee\u6570\u503c\n    deviation = sqrt((cos(2 * beta) * (xxNewValue - yyNewValue) + 2 * sin(2 * beta) * xyNewValue + (xxNewValue + yyNewValue)) \/ (2 * count));\nend\n<\/pre><\/div>","protected":false},"excerpt":{"rendered":"
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