{"id":2208,"date":"2023-07-23T06:23:05","date_gmt":"2023-07-23T06:23:05","guid":{"rendered":"https:\/\/statorials.org\/cn\/numpy-%e6%9f%a5%e6%89%be%e5%80%bc%e7%b4%a2%e5%bc%95\/"},"modified":"2023-07-23T06:23:05","modified_gmt":"2023-07-23T06:23:05","slug":"numpy-%e6%9f%a5%e6%89%be%e5%80%bc%e7%b4%a2%e5%bc%95","status":"publish","type":"post","link":"https:\/\/statorials.org\/cn\/numpy-%e6%9f%a5%e6%89%be%e5%80%bc%e7%b4%a2%e5%bc%95\/","title":{"rendered":"\u5982\u4f55\u5728 numpy \u6570\u7ec4\u4e2d\u67e5\u627e\u503c\u7d22\u5f15\uff08\u9644\u793a\u4f8b\uff09"},"content":{"rendered":"

<\/p>\n

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\u53ef\u4ee5\u4f7f\u7528\u4ee5\u4e0b\u65b9\u6cd5\u6765\u67e5\u627e NumPy \u6570\u7ec4\u4e2d\u7279\u5b9a\u503c\u7684\u7d22\u5f15\u4f4d\u7f6e\uff1a<\/span><\/p>\n

\u65b9\u6cd5\u4e00\uff1a\u67e5\u627e\u6240\u6709\u4ef7\u503c\u6307\u6570\u4f4d\u7f6e<\/strong><\/span><\/p>\n

 n.p. where<\/span> (x== value<\/span> )\n<\/strong><\/pre>\n
\u65b9\u6cd5\u4e8c\uff1a\u67e5\u627e\u7b2c\u4e00\u4e2a\u503c\u7d22\u5f15\u4f4d\u7f6e<\/strong><\/span><\/p>\n
 n.p. where<\/span> (x== value<\/span> )[0][0]<\/strong><\/pre>\n
\u65b9\u6cd5\u4e09\uff1a\u67e5\u627e\u591a\u4e2a\u503c\u7684\u7b2c\u4e00\u4e2a\u7d22\u5f15\u4f4d\u7f6e<\/strong><\/span><\/p>\n
 #define values of interest\n<\/span>vals = np. array<\/span> ([ value1<\/span> , value2<\/span> , value3<\/span> ])\n\n#find index location of first occurrence of each value of interest\n<\/span>exit = np. argsort<\/span> (x)\ngo out[np. searchsorted<\/span> (x, vals, sorter=sorter)]<\/strong><\/pre>\n
\u4ee5\u4e0b\u793a\u4f8b\u5c55\u793a\u4e86\u5982\u4f55\u5728\u5b9e\u8df5\u4e2d\u4f7f\u7528\u6bcf\u79cd\u65b9\u6cd5\u3002<\/span><\/p>\n
\u65b9\u6cd5\u4e00\uff1a\u67e5\u627e\u6240\u6709\u4ef7\u503c\u6307\u6570\u4f4d\u7f6e<\/strong><\/span><\/h3>\n
\u4ee5\u4e0b\u4ee3\u7801\u663e\u793a\u5982\u4f55\u5728 NumPy \u6570\u7ec4\u4e2d\u67e5\u627e\u7b49\u4e8e\u67d0\u4e2a\u503c\u7684\u6bcf\u4e2a\u7d22\u5f15\u4f4d\u7f6e\uff1a<\/span><\/p>\n
 import<\/span> numpy as<\/span> np\n\n#define array of values<\/span>\nx = np. array<\/span> ([4, 7, 7, 7, 8, 8, 8])\n\n#find all index positions where x is equal to 8<\/span>\nn.p. where<\/span> (x== 8<\/span> )\n\n(array([4, 5, 6]),)\n<\/span><\/span><\/strong><\/pre>\n
\u4ece\u7ed3\u679c\u4e2d\u6211\u4eec\u53ef\u4ee5\u770b\u5230\u7d22\u5f15\u4f4d\u7f6e 4\u30015 \u548c 6 \u90fd\u7b49\u4e8e\u503c8<\/strong> \u3002<\/span><\/p>\n
\u65b9\u6cd5\u4e8c\uff1a\u67e5\u627e\u7b2c\u4e00\u4e2a\u503c\u7d22\u5f15\u4f4d\u7f6e<\/strong><\/span><\/h3>\n
\u4ee5\u4e0b\u4ee3\u7801\u663e\u793a\u5982\u4f55\u5728 NumPy \u6570\u7ec4\u4e2d\u67e5\u627e\u7b49\u4e8e\u67d0\u4e2a\u503c\u7684\u7b2c\u4e00\u4e2a\u7d22\u5f15\u4f4d\u7f6e\uff1a<\/span><\/p>\n
 import<\/span> numpy as<\/span> np\n\n#define array of values\n<\/span>x = np. array<\/span> ([4, 7, 7, 7, 8, 8, 8])\n\n#find first index position where x is equal to 8\n<\/span>n.p. where<\/span> (x== 8<\/span> )[0][0]\n\n4\n<\/span><\/span><\/strong><\/pre>\n
\u4ece\u7ed3\u679c\u4e2d\u6211\u4eec\u53ef\u4ee5\u770b\u5230\uff0c\u503c8<\/strong>\u9996\u5148\u51fa\u73b0\u5728\u7d22\u5f15\u4f4d\u7f6e4\u5904\u3002<\/span><\/p>\n
\u65b9\u6cd5\u4e09\uff1a\u67e5\u627e\u591a\u4e2a\u503c\u7684\u7b2c\u4e00\u4e2a\u7d22\u5f15\u4f4d\u7f6e<\/strong><\/span><\/h3>\n
\u4ee5\u4e0b\u4ee3\u7801\u5c55\u793a\u4e86\u5982\u4f55\u67e5\u627e NumPy \u6570\u7ec4\u4e2d\u591a\u4e2a\u503c\u7684\u7b2c\u4e00\u4e2a\u7d22\u5f15\u4f4d\u7f6e\uff1a<\/span><\/p>\n
 import<\/span> numpy as<\/span> np\n\n#define array of values\n<\/span>x = np. array<\/span> ([4, 7, 7, 7, 8, 8, 8])\n\n#define values of interest\n<\/span>vals = np. array<\/span> ([4, 7, 8])\n\n#find index location of first occurrence of each value of interest\n<\/span>exit = np. argsort<\/span> (x)\ngo out[np. searchsorted<\/span> (x, vals, sorter=sorter)]\n\narray([0, 1, 4])\n<\/span><\/span><\/strong><\/pre>\n
\u4ece\u7ed3\u679c\u6211\u4eec\u53ef\u4ee5\u770b\u51fa\uff1a<\/span><\/p>\n