{"id":3601,"date":"2022-03-18T11:29:37","date_gmt":"2022-03-18T03:29:37","guid":{"rendered":"https:\/\/egonlin.com\/?p=3601"},"modified":"2022-03-18T11:29:37","modified_gmt":"2022-03-18T03:29:37","slug":"%e7%ac%ac%e4%b8%80%e8%8a%82%ef%bc%9anumpy","status":"publish","type":"post","link":"https:\/\/egonlin.com\/?p=3601","title":{"rendered":"\u7b2c\u4e00\u8282\uff1aNumpy"},"content":{"rendered":"<h1>Numpy<\/h1>\n<ul>\n<li>\u4ec0\u4e48\u662fnumpy<\/li>\n<li>\u4e3a\u4ec0\u4e48\u8981\u7528numpy<\/li>\n<li>\u600e\u4e48\u7528numpy\n<ul>\n<li>\u4e3a\u4ec0\u4e48\u8981\u7528ndarray<\/li>\n<li>ndarray-\u521b\u5efa<\/li>\n<li>\u591a\u7ef4\u6570\u7ec4\u5217\u8868<\/li>\n<li>\u5e38\u7528\u5c5e\u6027<\/li>\n<li>\u6570\u636e\u7c7b\u578b<\/li>\n<li>\u5411\u91cf\u5316\u6570\u5b66\u8fd0\u7b97<\/li>\n<li>\u7d22\u5f15\u548c\u5207\u7247<\/li>\n<\/ul>\n<\/li>\n<li>\u901a\u7528\u51fd\u6570\n<ul>\n<li>\u6570\u5b66\u7edf\u8ba1\u65b9\u6cd5<\/li>\n<li>\u968f\u673a\u6570<\/li>\n<\/ul>\n<\/li>\n<li>\u603b\u7ed3<\/li>\n<\/ul>\n<h2>1\u3001\u4ec0\u4e48\u662fNumpy<\/h2>\n<p>\u200b   NumPy\u662f\u4e00\u4e2a\u529f\u80fd\u5f3a\u5927\u7684Python\u5e93\uff0c\u4e3b\u8981\u7528\u4e8e\u5bf9\u591a\u7ef4\u6570\u7ec4\u6267\u884c\u8ba1\u7b97\u3002NumPy\u8fd9\u4e2a\u8bcd\u6765\u6e90\u4e8e\u4e24\u4e2a\u5355\u8bcd&#8211; Numerical\u548cPython\u3002<br \/>\n\u200b   \u5b83\u662f Python \u751f\u6001\u7cfb\u7edf\u4e2d\u6570\u636e\u5206\u6790\u3001\u673a\u5668\u5b66\u4e60\u548c\u79d1\u5b66\u8ba1\u7b97\u7684\u4e3b\u529b\u519b\u3002\u5b83\u6781\u5927\u5730\u7b80\u5316\u4e86\u5411\u91cf\u548c\u77e9\u9635\u7684\u64cd\u4f5c\u5904\u7406\u3002Python \u6570\u636e\u79d1\u5b66\u76f8\u5173\u7684\u4e00\u4e9b\u4e3b\u8981\u8f6f\u4ef6\u5305\uff08\u5982 scikit-learn\u3001SciPy\u3001pandas \u548c tensorflow\uff09\u90fd\u4ee5 NumPy \u4f5c\u4e3a\u5176\u67b6\u6784\u7684\u57fa\u7840\u90e8\u5206\u3002\u9664\u4e86\u80fd\u5bf9\u6570\u503c\u6570\u636e\u8fdb\u884c\u5207\u7247\uff08slice\uff09\u548c\u5207\u5757\uff08dice\uff09\u4e4b\u5916\uff0c\u4f7f\u7528 NumPy \u8fd8\u80fd\u4e3a\u5904\u7406\u548c\u8c03\u8bd5\u4e0a\u8ff0\u5e93\u4e2d\u7684\u9ad8\u7ea7\u5b9e\u4f8b\u5e26\u6765\u6781\u5927\u4fbf\u5229\u7ec4\u3002\u5b83\u5c06\u5e38\u7528\u7684\u6570\u5b66\u51fd\u6570\u90fd\u652f\u6301\u5411\u91cf\u5316\u8fd0\u7b97\uff0c\u4f7f\u5f97\u8fd9\u4e9b\u6570\u5b66\u51fd\u6570\u80fd\u591f\u76f4\u63a5\u5bf9\u6570\u7ec4\u8fdb\u884c\u64cd\u4f5c\uff0c\u5c06\u672c\u6765\u9700\u8981\u5728Python\u7ea7\u522b\u8fdb\u884c\u7684\u5faa\u73af\uff0c\u653e\u5230C\u8bed\u8a00\u7684\u8fd0\u7b97\u4e2d\uff0c\u660e\u663e\u5730\u63d0\u9ad8\u4e86\u7a0b\u5e8f\u7684\u8fd0\u7b97\u901f\u5ea6\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy1.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy1.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h2>2\u3001\u4e3a\u4ec0\u4e48\u8981\u7528Numpy<\/h2>\n<p>\u200b   NumPy\u662fPython\u4e2d\u7684\u4e00\u4e2a\u8fd0\u7b97\u901f\u5ea6\u975e\u5e38\u5feb\u7684\u4e00\u4e2a\u6570\u5b66\u5e93\uff0c\u5b83\u975e\u5e38\u91cd\u89c6\u6570\u7ec4\u3002\u5b83\u5141\u8bb8\u4f60\u5728Python\u4e2d\u8fdb\u884c\u5411\u91cf\u548c\u77e9\u9635\u8ba1\u7b97\uff0c\u5e76\u4e14\u7531\u4e8e\u8bb8\u591a\u5e95\u5c42\u51fd\u6570\u5b9e\u9645\u4e0a\u662f\u7528C\u7f16\u5199\u7684\uff0c\u56e0\u6b64\u4f60\u53ef\u4ee5\u4f53\u9a8c\u5728\u539f\u751fPython\u4e2d\u6c38\u8fdc\u65e0\u6cd5\u4f53\u9a8c\u5230\u7684\u901f\u5ea6\u3002<\/p>\n<pre><code class=\"language-python\">import numpy as np\nimport time\n\n# \u7528python\u81ea\u5e26\u65b9\u6cd5\u5904\u7406\ndef func(values):\n    result = []\n    for v in values:\n        result.append(v * v)\n    return result\ndata = range(10000)\n%timeit func(data)\n\u8fd0\u884c\u7ed3\u679c\uff1a\n1.07 ms \u00b1 20.5 \u00b5s per loop (mean \u00b1 std. dev. of 7 runs, 1000 loops each)\n\n# \u7528numpy\u4e2d\u7684\u65b9\u6cd5\u5904\u7406\narr = np.arange(0,10000)\n%timeit arr ** arr\n\u8fd0\u884c\u7ed3\u679c\uff1a\n397 \u00b5s \u00b1 32.5 \u00b5s per loop (mean \u00b1 std. dev. of 7 runs, 1000 loops each)<\/code><\/pre>\n<p>\u200b   NumPy\u7edd\u5bf9\u662f\u79d1\u5b66Python\u6210\u529f\u7684\u5173\u952e\u4e4b\u4e00\uff0c\u5982\u679c\u4f60\u60f3\u8981\u8fdb\u5165Python\u4e2d\u7684\u6570\u636e\u79d1\u5b66\u6216\u673a\u5668\u5b66\u4e60\uff0c\u4f60\u5c31\u8981\u5fc5\u987b\u5b66\u4e60\u5b83\u3002\u4ece\u6700\u540e\u7684\u6267\u884c\u7ed3\u679c\u6765\u770bnumpy\u7684\u5904\u7406\u901f\u5ea6\u8981\u6bd4python\u7684\u5904\u7406\u901f\u5ea6\u5feb\u4e0a\u5341\u51e0\u500d\uff0c\u5f53\u7136\u8fd9\u53ea\u662f\u5b83\u7684\u5176\u4e2d\u4e00\u9879\u4f18\u52bf\uff0c\u4e0b\u9762\u5c31\u901a\u8fc7\u4e00\u4e9b\u5177\u4f53\u7684\u64cd\u4f5c\u6765\u770b\u4e00\u770bnumpy\u7684\u7528\u6cd5\u4e0e\u4f18\u52bf\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy2.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy2.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h2>3\u3001\u600e\u4e48\u7528Numpy<\/h2>\n<p>\u5b89\u88c5\u65b9\u6cd5\uff1a<\/p>\n<blockquote>\n<p>pip install numpy<\/p>\n<\/blockquote>\n<p>\u5f15\u7528\u65b9\u5f0f\uff1a<\/p>\n<blockquote>\n<p>import numpy as np<\/p>\n<\/blockquote>\n<p>\u8fd9\u662f\u5b98\u65b9\u8ba4\u8bc1\u7684\u5bfc\u5165\u65b9\u5f0f\uff0c\u53ef\u80fd\u4f1a\u6709\u4eba\u8bf4\u4e3a\u4ec0\u4e48\u4e0d\u7528<code>from numpy import *<\/code>,\u662f\u56e0\u4e3a\u5728numpy\u5f53\u4e2d\u6709\u4e00\u4e9b\u65b9\u6cd5\u4e0ePython\u4e2d\u81ea\u5e26\u7684\u4e00\u4e9b\u65b9\u6cd5\uff0c\u4f8b\u5982<code>max<\/code>\u3001<code>min<\/code>\u7b49\u51b2\u7a81\uff0c\u4e3a\u4e86\u907f\u514d\u8fd9\u4e9b\u9ebb\u70e6\u5927\u5bb6\u5c31\u7ea6\u5b9a\u4fd7\u6210\u7684\u90fd\u4f7f\u7528\u8fd9\u79cd\u65b9\u6cd5\u3002<\/p>\n<p>Numpy\u7684\u6838\u5fc3\u7279\u5f81\u5c31\u662fN-\u7ef4\u6570\u7ec4\u5bf9\u2014\u2014ndarray.<\/p>\n<h3>3.1\u3001\u4e3a\u4ec0\u4e48\u8981\u7528ndarray?<\/h3>\n<p>\u200b   numpy\u6240\u6709\u7684\u64cd\u4f5c\u90fd\u662f\u56f4\u7ed5\u7740\u6570\u7ec4\u5c55\u5f00\u7684\uff0c\u8fd9\u4e2a\u6570\u7ec4\u7684\u540d\u5b57\u5c31\u53eb\u505a<code>ndarray<\/code>,\u5728\u5b66\u4e60ndarray\u6570\u7ec4\u4e4b\u524d\u80af\u5b9a\u6709\u4eba\u4f1a\u8bf4\u8fd9\u4e2a\u4e1c\u897f\u548cPython\u4e2d\u7684\u5217\u8868\u5dee\u4e0d\u591a\u554a\uff0c\u4e3a\u4ec0\u4e48\u4e0d\u7528\u5217\u8868\u5462\uff0c\u5217\u8868\u8fd8\u8981\u65b9\u4fbf\u4e9b\u3002\u5176\u5b9e\u5217\u8868list\u672c\u8eab\u662f\u4e3a\u4e86\u5904\u7406\u66f4\u5e7f\u6cdb\u3001\u66f4\u901a\u7528\u7684\u76ee\u7684\u800c\u6784\u5efa\u7684\uff0c\u5176\u5b9e\u4ece\u8fd9\u4e00\u65b9\u9762\u6765\u770bndarray\u5bf9\u4e8e\u5904\u7406\u8fd9\u4e2a\u6570\u7ec4\u7c7b\u578b\u7ed3\u6784\u7684\u6570\u636e\u4f1a\u66f4\u52a0\u65b9\u4fbf\u3002<\/p>\n<p>\u63a5\u4e0b\u6765\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u5177\u4f53\u7684\u5b9e\u4f8b\u6765\u5c55\u793a\u4e00\u4e0bndarray\u7684\u4f18\u52bf\u3002<br \/>\n\u73b0\u5728\u6709\u8fd9\u6837\u4e00\u4e2a\u9700\u6c42:<\/p>\n<pre><code>\u5df2\u77e5\u82e5\u5e72\u5bb6\u8de8\u56fd\u516c\u53f8\u7684\u5e02\u503c\uff08\u7f8e\u5143\uff09\uff0c\u5c06\u5176\u6362\u7b97\u4e3a\u4eba\u6c11\u5e01<\/code><\/pre>\n<p>\u6309\u7167Python\u5f53\u4e2d\u7684\u65b9\u6cd5<br \/>\n\u7b2c\u4e00\u79cd\uff1a\u662f\u5c06\u6240\u6709\u7684\u7f8e\u5143\u901a\u8fc7for\u5faa\u73af\u4f9d\u6b21\u8fed\u4ee3\u51fa\u6765\uff0c\u7136\u540e\u7528\u6bcf\u4e2a\u516c\u53f8\u7684\u5e02\u503c\u4e58\u4ee5\u6c47\u7387<br \/>\n\u7b2c\u4e8c\u79cd\uff1a\u901a\u8fc7map\u65b9\u6cd5\u548clambda\u51fd\u6570\u6620\u5c04<\/p>\n<p>\u8fd9\u4e9b\u65b9\u6cd5\u76f8\u5bf9\u6765\u8bf4\u4e5f\u633a\u597d\u7528\u7684\uff0c\u4f46\u662f\u518d\u6765\u770b\u901a\u8fc7ndarray\u5bf9\u8c61\u662f\u5982\u4f55\u8ba1\u7b97\u7684<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy1-2.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy1-2.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u901a\u8fc7ndarray\u8fd9\u4e2a\u591a\u7ef4\u6570\u7ec4\u5bf9\u8c61\u53ef\u4ee5\u8ba9\u8fd9\u4e9b\u6279\u91cf\u8ba1\u7b97\u53d8\u5f97\u66f4\u52a0\u7b80\u5355\uff0c\u5f53\u7136\u8fd9\u53ea\u5b83\u5176\u4e2d\u4e00\u79cd\u4f18\u52bf\uff0c\u63a5\u4e0b\u6765\u5c31\u901a\u8fc7\u5177\u4f53\u7684\u64cd\u4f5c\u6765\u53d1\u73b0\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy3.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy3.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>3.2\u3001ndarray-\u521b\u5efa<\/h3>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: center;\">\u65b9\u6cd5<\/th>\n<th style=\"text-align: center;\">\u63cf\u8ff0<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: center;\">array()<\/td>\n<td style=\"text-align: center;\">\u5c06\u5217\u8868\u8f6c\u6362\u4e3a\u6570\u7ec4\uff0c\u53ef\u9009\u62e9\u663e\u5f0f\u6307\u5b9adtype<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">arange()<\/td>\n<td style=\"text-align: center;\">range\u7684numpy\u7248\uff0c\u652f\u6301\u6d6e\u70b9\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">linspace()<\/td>\n<td style=\"text-align: center;\">\u7c7b\u4f3carange()\uff0c\u7b2c\u4e09\u4e2a\u53c2\u6570\u4e3a\u6570\u7ec4\u957f\u5ea6<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">zeros()<\/td>\n<td style=\"text-align: center;\">\u6839\u636e\u6307\u5b9a\u5f62\u72b6\u548cdtype\u521b\u5efa\u51680\u6570\u7ec4<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">ones()<\/td>\n<td style=\"text-align: center;\">\u6839\u636e\u6307\u5b9a\u5f62\u72b6\u548cdtype\u521b\u5efa\u51681\u6570\u7ec4<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">empty()<\/td>\n<td style=\"text-align: center;\">\u6839\u636e\u6307\u5b9a\u5f62\u72b6\u548cdtype\u521b\u5efa\u7a7a\u6570\u7ec4\uff08\u968f\u673a\u503c\uff09<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">eye()<\/td>\n<td style=\"text-align: center;\">\u6839\u636e\u6307\u5b9a\u8fb9\u957f\u548cdtype\u521b\u5efa\u5355\u4f4d\u77e9\u9635<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u521b\u5efa.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u521b\u5efa.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<pre><code class=\"language-python\">\n1\u3001arange():\nnp.arange(1.2,10,0.4)\n\u6267\u884c\u7ed3\u679c\uff1a\narray([1.2, 1.6, 2. , 2.4, 2.8, 3.2, 3.6, 4. , 4.4, 4.8, 5.2, 5.6, 6. ,\n       6.4, 6.8, 7.2, 7.6, 8. , 8.4, 8.8, 9.2, 9.6])\n# \u5728\u8fdb\u884c\u6570\u636e\u5206\u6790\u7684\u65f6\u5019\u901a\u5e38\u6211\u4eec\u9047\u5230\u5c0f\u6570\u7684\u673a\u4f1a\u8fdc\u8fdc\u5927\u4e8e\u9047\u5230\u6574\u6570\u7684\u673a\u4f1a\uff0c\u8fd9\u4e2a\u65b9\u6cd5\u4e0ePython\u5185\u7f6e\u7684range\u7684\u4f7f\u7528\u65b9\u6cd5\u4e00\u6837\n-----------------------------------------------------------------\n2\u3001linspace()\nnp.linspace(1,10,20)\n\u6267\u884c\u7ed3\u679c\uff1a\narray([ 1.        ,  1.47368421,  1.94736842,  2.42105263,  2.89473684,\n        3.36842105,  3.84210526,  4.31578947,  4.78947368,  5.26315789,\n        5.73684211,  6.21052632,  6.68421053,  7.15789474,  7.63157895,\n        8.10526316,  8.57894737,  9.05263158,  9.52631579, 10.        ])\n# \u8fd9\u4e2a\u65b9\u6cd5\u4e0earange\u6709\u4e00\u4e9b\u533a\u522b\uff0carange\u662f\u987e\u5934\u4e0d\u987e\u5c3e\uff0c\u800c\u8fd9\u4e2a\u65b9\u6cd5\u662f\u987e\u5934\u53c8\u987e\u5c3e\uff0c\u57281\u523010\u4e4b\u95f4\u751f\u6210\u7684\u4e8c\u5341\u4e2a\u6570\u6bcf\u4e2a\u6570\u5b57\u4e4b\u95f4\u7684\u8ddd\u79bb\u76f8\u7b49\u7684\uff0c\u524d\u540e\u4e24\u4e2a\u6570\u505a\u51cf\u6cd5\u80af\u5b9a\u76f8\u7b49\n----------------------------------------------------------------\n3\u3001zeros()\nnp.zeros((3,4))\n\u6267\u884c\u7ed3\u679c\uff1a\narray([[0., 0., 0., 0.],\n       [0., 0., 0., 0.],\n       [0., 0., 0., 0.]])\n# \u4f1a\u75280\u751f\u6210\u4e09\u884c\u56db\u5217\u7684\u4e00\u4e2a\u591a\u7ef4\u6570\u7ec4\n---------------------------------------------------------------------\n4\u3001ones()\nnp.ones((3,4))\n\u6267\u884c\u7ed3\u679c\uff1a\narray([[1., 1., 1., 1.],\n       [1., 1., 1., 1.],\n       [1., 1., 1., 1.]])\n# \u4f1a\u75281\u751f\u6210\u4e09\u884c\u56db\u5217\u7684\u4e00\u4e2a\u591a\u7ef4\u6570\u7ec4\n------------------------------------------------------------------------\n5\u3001empty()\nnp.empty(10)\n\u6267\u884c\u7ed3\u679c\uff1a\narray([1., 1., 1., 1., 1., 1., 1., 1., 1., 1.])\n# \u8fd9\u4e2a\u65b9\u6cd5\u53ea\u7533\u8bf7\u5185\u5b58\uff0c\u4e0d\u7ed9\u5b83\u8d4b\u503c\n-----------------------------------------------------------------------\n6\u3001eye()\nnp.eye(5)\n\u6267\u884c\u7ed3\u679c\uff1a\narray([[1., 0., 0., 0., 0.],\n       [0., 1., 0., 0., 0.],\n       [0., 0., 1., 0., 0.],\n       [0., 0., 0., 1., 0.],\n       [0., 0., 0., 0., 1.]])\n# \u5bf9\u89d2\u77e9\u9635<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy4.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy4.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>3.3\u3001ndarray\u662f\u4e00\u4e2a\u591a\u7ef4\u6570\u7ec4\u5217\u8868<\/h3>\n<p>\u63a5\u4e0b\u6765\u5c31\u591a\u7ef4\u6570\u7ec4\u4e3e\u4e2a\u4f8b\u5b50\uff1a<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='\u914d\u56fe\/numpy2.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"\u914d\u56fe\/numpy2.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"numpy2\" \/><\/div><\/p>\n<p>\u200b   \u4e3a\u4e86\u521b\u5efa\u4e00\u4e2a2\u7ef4\u6570\u7ec4\uff0c\u6211\u4eec\u662f\u4f20\u9012\u4e86\u4e00\u4e2a\u5217\u8868\u7684\u5217\u8868\u7ed9\u8fd9\u4e2aarray()\u51fd\u6570\u3002\u5982\u679c\u6211\u4eec\u60f3\u8981\u7684\u662f\u4e00\u4e2a\u4e09\u7ef4\u6570\u7ec4\uff0c\u6211\u4eec\u5c31\u5fc5\u987b\u8981\u4e00\u4e2a\u5217\u8868\u7684\u5217\u8868\u7684\u5217\u8868\uff08\u4e5f\u5c31\u662f\u4e09\u5c42\u5217\u8868\uff09\uff0c\u4ee5\u6b64\u7c7b\u63a8\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u591a\u7ef4\u6570\u7ec4.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u591a\u7ef4\u6570\u7ec4.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u5f88\u591a\u60c5\u51b5\u4e0b\uff0c\u5904\u7406\u4e00\u4e2a\u65b0\u7684\u7ef4\u5ea6\u53ea\u9700\u8981\u5728numpy\u51fd\u6570\u7684\u53c2\u6570\u4e2d\u6dfb\u52a0\u4e00\u4e2a\u9017\u53f7<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u591a\u7ef4\u6570\u7ec4\u7528\u6cd5.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u591a\u7ef4\u6570\u7ec4\u7528\u6cd5.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u6709\u7684\u4eba\u53ef\u80fd\u4f1a\u8bf4\u4e86\uff0c\u8fd9\u4e2a\u6570\u7ec4\u8ddfPython\u4e2d\u7684\u5217\u8868\u5f88\u50cf\u554a\uff0c\u5b83\u548c\u5217\u8868\u6709\u4ec0\u4e48\u533a\u522b\u5462\uff1f<\/p>\n<pre><code class=\"language-python\">&#039;&#039;&#039;\n    \u5728python\u4e2d\u5217\u8868\u662f\u53ef\u4ee5\u5b58\u4efb\u610f\u7c7b\u578b\u7684\u503c\u7684\uff0c\u4f46\u662f\u5728\u6570\u7ec4\u5f53\u4e2d\u7684\u5143\u7d20\u5fc5\u987b\u7c7b\u578b\u5fc5\u987b\u76f8\u540c\u3002\u8fd9\u662f\u56e0\u4e3a\u5217\u8868\u4e2d\u5b58\u7684\u53ea\u662f\u6bcf\u4e2a\u5143\u7d20\u7684\u5730\u5740\uff0c\u4e0d\u7ba1\u8fd0\u884c\u591a\u5c11\u6b21\uff0c\u503c\u7684\u4f4d\u7f6e\u662f\u4e0d\u4f1a\u6539\u53d8\u7684\uff0c\u4e0d\u9700\u8981\u5728\u610f\u6570\u636e\u7684\u7c7b\u578b\uff1b\u800c\u5728ndarray\u5f53\u4e2d\u5b58\u7684\u662f\u5177\u4f53\u7684\u503c\uff0c\u6bcf\u4e00\u6b21\u6267\u884c\u90fd\u662f\u91cd\u65b0\u5b58\u653e\u3002\n&#039;&#039;&#039;\nl1 = [&#039;1&#039;,&#039;2&#039;,4]\nna = np.array(l1)\nprint(f&quot;ndarry:{id(na[0])}&quot;)\nprint(f&quot;list:{id(l1[0])}&quot;)\n\n> ndarry:2140960887632\n  list:2140897577592\n&quot;&quot;&quot;\n\u901a\u8fc7\u591a\u6b21\u6267\u884c\u5176\u5b9e\u5c31\u53ef\u4ee5\u53d1\u73b0\uff0cndarray\u6570\u7ec4\u7684id\u503c\u4e00\u76f4\u5728\u4e0d\u505c\u7684\u6362\uff0c\u800clist\u7684id\u503c\u59cb\u7ec8\u4fdd\u6301\u4e0d\u53d8\n&quot;&quot;&quot;<\/code><\/pre>\n<ul>\n<li>\u6570\u7ec4\u5bf9\u8c61\u5185\u7684\u5143\u7d20\u7c7b\u578b\u5fc5\u987b\u76f8\u540c<\/li>\n<li>\u6570\u7ec4\u5927\u5c0f\u4e0d\u53ef\u4fee\u6539<\/li>\n<\/ul>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy5.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy5.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>3.4\u3001\u5e38\u7528\u5c5e\u6027<\/h3>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: center;\">\u5c5e\u6027<\/th>\n<th style=\"text-align: center;\">\u63cf\u8ff0<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: center;\">T<\/td>\n<td style=\"text-align: center;\">\u6570\u7ec4\u7684\u8f6c\u7f6e\uff08\u5bf9\u9ad8\u7ef4\u6570\u7ec4\u800c\u8a00\uff09<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">dtype<\/td>\n<td style=\"text-align: center;\">\u6570\u7ec4\u5143\u7d20\u7684\u6570\u636e\u7c7b\u578b<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">size<\/td>\n<td style=\"text-align: center;\">\u6570\u7ec4\u5143\u7d20\u7684\u4e2a\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">ndim<\/td>\n<td style=\"text-align: center;\">\u6570\u7ec4\u7684\u7ef4\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">shape<\/td>\n<td style=\"text-align: center;\">\u6570\u7ec4\u7684\u7ef4\u5ea6\u5927\u5c0f\uff08\u4ee5\u5143\u7ec4\u5f62\u5f0f\uff09<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">itemsize<\/td>\n<td style=\"text-align: center;\">\u6bcf\u4e2a\u9879\u5360\u7528\u7684\u5b57\u8282\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">nbytes<\/td>\n<td style=\"text-align: center;\">\u6570\u7ec4\u4e2d\u7684\u6240\u6709\u6570\u636e\u6d88\u8017\u6389\u7684\u5b57\u8282\u6570<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<pre><code class=\"language-python\"># T:\u8f6c\u7f6e \u8f6c\u7f6e\u662f\u4e00\u79cd\u7279\u6b8a\u7684\u6570\u636e\u91cd\u7ec4\u5f62\u5f0f\uff0c\u53ef\u4ee5\u8fd4\u56de\u5e95\u5c42\u6570\u636e\u7684\u89c6\u56fe\u800c\u4e0d\u9700\u8981\u590d\u5236\u4efb\u4f55\u5185\u5bb9\u3002\n# \u901a\u4fd7\u70b9\u8bf4\uff0c\u8f6c\u7f6e\u5c31\u662f\u5c06\u6570\u636e\u65cb\u8f6c90\u5ea6\uff0c\u884c\u53d8\u6210\u5217\uff0c\u5217\u53d8\u6210\u884c\u3002\n\nli1 = [\n    [1,2,3],\n    [4,5,6]\n] \na = np.array(li1)\na.T\n\u6267\u884c\u7ed3\u679c\uff1a\narray([[1, 4],\n       [2, 5],\n       [3, 6]])<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='\u914d\u56fe\/np\u8f6c\u7f6e.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"\u914d\u56fe\/np\u8f6c\u7f6e.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"np\u8f6c\u7f6e\" \/><\/div><\/p>\n<pre><code class=\"language-python\">\n# dtype\uff1a\u8fd4\u56de\u5f53\u524d\u6570\u636e\u7684\u6570\u636e\u7c7b\u578b\narr = np.arange(10)\narr.dtype\n\u6267\u884c\u7ed3\u679c\uff1a\ndtype(&#039;int32&#039;)\n\n# size\uff1a\u8fd4\u56de\u5f53\u524d\u6570\u7ec4\u5185\u5b58\u5728\u7684\u5143\u7d20\u4e2a\u6570\nl1 = [[[1,2,3],\n       [4,5,6]],\n     [[7,8,9],\n     [1,5,9]\n     ]]\narr1 = np.array(l1)\narr1.size\n\u6267\u884c\u7ed3\u679c\uff1a\n12\n\n# ndim\uff1a\u8fd4\u56de\u5f53\u524d\u6570\u7ec4\u7ef4\u5ea6\nl1 = [[[1,2,3],\n       [4,5,6]],\n     [[7,8,9],\n     [1,5,9]\n     ]]\narr1 = np.array(l1)\narr1.ndim\n\u6267\u884c\u7ed3\u679c\uff1a\n3\n\n# shape\uff1a\u8fd4\u56de\u6570\u7ec4\u7ef4\u5ea6\u5927\u5c0f\nl1 = [[[1,2,3,4],\n       [4,5,6,5],\n      [6,8,3,6]],\n     [[7,8,9,7],\n     [1,5,9,7],\n      [4,6,8,4]\n     ]]\narr1 = np.array(l1)\narr1.shape\n\u6267\u884c\u7ed3\u679c\uff1a\n(2, 3, 4)\n&quot;&quot;&quot;\n\u6700\u7ec8\u4e09\u4e2a\u53c2\u6570\u4ee3\u8868\u7684\u542b\u4e49\u4f9d\u6b21\u4e3a\uff1a\u4e8c\u7ef4\u7ef4\u5ea6\uff0c\u4e09\u7ef4\u7ef4\u5ea6\uff0c\u6bcf\u4e2a\u6570\u7ec4\u5185\u6570\u636e\u5927\u5c0f\n\n\u8981\u6ce8\u610f\u8fd9\u4e9b\u6570\u7ec4\u5fc5\u987b\u8981\u662f\u76f8\u540c\u5927\u5c0f\u624d\u53ef\u4ee5\n&quot;&quot;&quot;<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy6.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy6.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>3.5\u3001\u6570\u636e\u7c7b\u578b<\/h3>\n<ul>\n<li>dtype<\/li>\n<\/ul>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: center;\">\u7c7b\u578b<\/th>\n<th style=\"text-align: center;\">\u63cf\u8ff0<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: center;\">\u5e03\u5c14\u578b<\/td>\n<td style=\"text-align: center;\">bool_<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">\u6574\u578b<\/td>\n<td style=\"text-align: center;\">int_ int8 int16 int32 int 64<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">\u65e0\u7b26\u53f7\u6574\u578b<\/td>\n<td style=\"text-align: center;\">uint8 uint16 uint32 uint64<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">\u6d6e\u70b9\u578b<\/td>\n<td style=\"text-align: center;\">float_ float16 float32 float64<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<pre><code class=\"language-python\">\u6574\u578b\uff1a\nint32\u53ea\u80fd\u8868\u793a(-2**31\uff0c2**31-1),\u56e0\u4e3a\u5b83\u53ea\u670932\u4e2a\u4f4d\uff0c\u53ea\u80fd\u8868\u793a2**32\u4e2a\u6570\n\n\u65e0\u7b26\u53f7\u6574\u578b\uff1a\n\u53ea\u80fd\u7528\u6765\u5b58\u6b63\u6570\uff0c\u4e0d\u80fd\u7528\u6765\u5b58\u8d1f\u6570\n\n&quot;&quot;&quot;\n\u8865\u5145\uff1a\nastype()\u65b9\u6cd5\u53ef\u4ee5\u4fee\u6539\u6570\u7ec4\u7684\u6570\u636e\u7c7b\u578b\n\u793a\u4f8b\uff1a \ndata.astype(np.float)\n&quot;&quot;&quot;<\/code><\/pre>\n<h3>3.6\u3001\u5411\u91cf\u5316\u6570\u5b66\u8fd0\u7b97<\/h3>\n<ul>\n<li>\u6570\u7ec4\u548c\u6807\u91cf(\u6570\u5b57)\u4e4b\u95f4\u8fd0\u7b97<\/li>\n<\/ul>\n<pre><code class=\"language-python\">li1 = [\n    [1,2,3],\n    [4,5,6] \n] \na = np.array(li1)\na * 2\n\u8fd0\u884c\u7ed3\u679c:\narray([[ 2,  4,  6],\n       [ 8, 10, 12]])<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u6570\u7ec4\u4e0e\u6807\u91cf.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u6570\u7ec4\u4e0e\u6807\u91cf.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u4e0e\u6807\u91cf\u4e4b\u95f4\u8fdb\u884c\u5411\u91cf\u5316\u8fd0\u7b97\uff0c\u591a\u7ef4\u6570\u7ec4\u4e0e\u4e00\u7ef4\u6570\u7ec4\u6ca1\u6709\u4efb\u4f55\u533a\u522b\uff0c\u90fd\u4f1a\u5c06\u4f60\u8981\u8fd0\u7b97\u7684\u6570\u5b57\u6620\u5c04\u5230\u6570\u7ec4\u4e2d\u7684\u6bcf\u4e00\u4e2a\u5143\u7d20\u4e0a\u8fdb\u884c\u8fd0\u7b97<\/p>\n<ul>\n<li>\u540c\u6837\u5927\u5c0f\u6570\u7ec4\u4e4b\u95f4\u7684\u8fd0\u7b97<\/li>\n<\/ul>\n<pre><code class=\"language-python\"># l2\u6570\u7ec4\nl2 = [\n    [1,2,3],\n    [4,5,6]\n]\na = np.array(l2)\n\n# l3\u6570\u7ec4\nl3 = [\n    [7,8,9],\n    [10,11,12]\n]\nb = np.array(l3)\n\na + b  # \u8ba1\u7b97\n\n\u6267\u884c\u7ed3\u679c\uff1a\narray([[ 8, 10, 12],\n       [14, 16, 18]])<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u6570\u7ec4\u4e0e\u6570\u7ec4.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u6570\u7ec4\u4e0e\u6570\u7ec4.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u6570\u7ec4\u4e0e\u6570\u7ec4\u4e4b\u95f4\u7684\u5411\u91cf\u5316\u8fd0\u7b97\uff0c\u4e24\u4e2a\u8fd0\u7b97\u7684\u6570\u7ec4\u5fc5\u987b\u76f8\u540c\u5927\u5c0f\uff0c\u5426\u5219\u4f1a\u62a5\u9519<\/p>\n<h3>3.7\u3001\u7d22\u5f15\u548c\u5207\u7247<\/h3>\n<ul>\n<li>\u7d22\u5f15<\/li>\n<\/ul>\n<p>\u4e00\u7ef4\u7d22\u5f15\u4f7f\u7528\u4e0epython\u672c\u8eab\u7684\u5217\u8868\u6ca1\u6709\u4efb\u4f55\u533a\u522b\uff0c\u6240\u4ee5\u63a5\u4e0b\u6765\u4e3b\u8981\u9488\u5bf9\u5927\u7684\u662f\u591a\u7ef4\u6570\u7ec4<\/p>\n<pre><code class=\"language-python\"># np\u91cd\u5851\narr = np.arange(30).reshape(5,6) # \u540e\u9762\u7684\u53c2\u65706\u53ef\u4ee5\u6539\u4e3a-1\uff0c\u76f8\u5f53\u4e8e\u5360\u4f4d\u7b26\uff0c\u7cfb\u7edf\u53ef\u4ee5\u81ea\u52a8\u5e2e\u5fd9\u7b97\u51e0\u5217<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='\u914d\u56fe\/np\u91cd\u5851.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"\u914d\u56fe\/np\u91cd\u5851.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"np\u91cd\u5851\" \/><\/div><\/p>\n<pre><code class=\"language-python\"># \u5c06\u4e8c\u7ef4\u53d8\u4e00\u7ef4\narr.reshape(30)\n\n# \u7d22\u5f15\u4f7f\u7528\u65b9\u6cd5\narray([[ 0,  1,  2,  3,  4,  5],\n       [ 6,  7,  8,  9, 10, 11],\n       [12, 13, 14, 15, 16, 17],\n       [18, 19, 20, 21, 22, 23],\n       [24, 25, 26, 27, 28, 29]])\n\n\u73b0\u5728\u6709\u8fd9\u6837\u4e00\u7ec4\u6570\u636e\uff0c\u9700\u6c42\uff1a\u627e\u523020\n\n\u5217\u8868\u5199\u6cd5\uff1aarr[3][2]\n\u6570\u7ec4\u5199\u6cd5\uff1aarr[3,2]  # \u4e2d\u95f4\u901a\u8fc7\u9017\u53f7\u9694\u5f00\u5c31\u53ef\u4ee5\u4e86<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u7d22\u5f15.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u7d22\u5f15.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<ul>\n<li>\u5207\u7247<\/li>\n<\/ul>\n<pre><code class=\"language-python\">arr\u6570\u7ec4\narray([[ 0,  1,  2,  3,  4,  5],\n       [ 6,  7,  8,  9, 10, 11],\n       [12, 13, 14, 15, 16, 17],\n       [18, 19, 20, 21, 22, 23],\n       [24, 25, 26, 27, 28, 29]])\n\narr[0,1:4]  # &gt;&gt;array([1, 2, 3])\narr[1:4,0]  # &gt;&gt;array([ 6, 12, 18])\narr[::2,::2] # &gt;&gt;array([[ 0,  2,  4],\n             #           [12, 14, 16],\n             #           [24, 26, 28]])\narr[:,1]  # &gt;&gt;array([ 1,  7, 13, 19, 25])<\/code><\/pre>\n<p>\u5207\u7247\u4e0d\u4f1a\u62f7\u8d1d\uff0c\u76f4\u63a5\u4f7f\u7528\u7684\u539f\u89c6\u56fe\uff0c\u5982\u679c\u786c\u8981\u62f7\u8d1d\uff0c\u9700\u8981\u5728\u540e\u9762\u52a0.copy()\u65b9\u6cd5<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy\u5207\u7247.png'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy\u5207\u7247.png\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u6700\u540e\u4f1a\u53d1\u73b0\u4fee\u6539\u5207\u7247\u540e\u7684\u6570\u636e\u5f71\u54cd\u7684\u4f9d\u7136\u662f\u539f\u6570\u636e\u3002\u6709\u7684\u4eba\u53ef\u80fd\u5bf9\u4e00\u70b9\u673a\u5236\u6709\u4e00\u4e9b\u4e0d\u7406\u89e3\u7684\u5730\u65b9\uff0c\u50cfPython\u4e2d\u5185\u7f6e\u7684\u90fd\u6709\u8d4b\u503c\u7684\u673a\u5236\uff0c\u800cNumpy\u53bb\u6ca1\u6709\uff0c\u5176\u5b9e\u662f\u56e0\u4e3aNumPy\u7684\u8bbe\u8ba1\u76ee\u7684\u662f\u5904\u7406\u5927\u6570\u636e\uff0c\u6240\u4ee5\u4f60\u53ef\u4ee5\u60f3\u8c61\u4e00\u4e0b\uff0c\u5047\u5982NumPy\u575a\u6301\u8981\u5c06\u6570\u636e\u590d\u5236\u6765\u590d\u5236\u53bb\u7684\u8bdd\u4f1a\u4ea7\u751f\u4f55\u7b49\u7684\u6027\u80fd\u548c\u5185\u5b58\u95ee\u9898\u3002<\/p>\n<ul>\n<li>\u5e03\u5c14\u578b\u7d22\u5f15<\/li>\n<\/ul>\n<p>\u73b0\u5728\u6709\u8fd9\u6837\u4e00\u4e2a\u9700\u6c42\uff1a\u7ed9\u4e00\u4e2a\u6570\u7ec4\uff0c\u9009\u51fa\u6570\u7ec4\u79cd\u6240\u6709\u5927\u4e8e5\u7684\u6570\u3002<\/p>\n<pre><code class=\"language-python\">li = [random.randint(1,10) for _ in range(30)]\na = np.array(li)\na[a&gt;5]\n\u6267\u884c\u7ed3\u679c\uff1a\narray([10,  7,  7,  9,  7,  9, 10,  9,  6,  8,  7,  6])\n----------------------------------------------\n\u539f\u7406:\na&gt;5\u4f1a\u5bf9a\u4e2d\u7684\u6bcf\u4e00\u4e2a\u5143\u7d20\u8fdb\u884c\u5224\u65ad\uff0c\u8fd4\u56de\u4e00\u4e2a\u5e03\u5c14\u6570\u7ec4\na &gt; 5\u7684\u8fd0\u884c\u7ed3\u679c\uff1a\narray([False,  True, False,  True,  True, False,  True, False, False,\n       False, False, False, False, False, False,  True, False,  True,\n       False, False,  True,  True,  True,  True,  True, False, False,\n       False, False,  True])\n----------------------------------------------\n\u5e03\u5c14\u578b\u7d22\u5f15\uff1a\u5c06\u540c\u6837\u5927\u5c0f\u7684\u5e03\u5c14\u6570\u7ec4\u4f20\u8fdb\u7d22\u5f15\uff0c\u4f1a\u8fd4\u56de\u4e00\u4e2a\u6709True\u5bf9\u5e94\u4f4d\u7f6e\u7684\u5143\u7d20\u7684\u6570\u7ec4<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy7.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy7.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u5e03\u5c14\u578b\u7d22\u5f15\u662fnumpy\u5f53\u4e2d\u7684\u4e00\u4e2a\u975e\u5e38\u5e38\u7528\u7684\u7528\u6cd5\uff0c\u901a\u8fc7\u5e03\u5c14\u578b\u7d22\u5f15\u53d6\u503c\u65b9\u4fbf\u53c8\u5feb\u6377\u3002<\/p>\n<h2>4\u3001\u901a\u7528\u51fd\u6570<\/h2>\n<blockquote>\n<p>\u80fd\u5bf9\u6570\u7ec4\u4e2d\u6240\u6709\u5143\u7d20\u540c\u65f6\u8fdb\u884c\u8fd0\u7b97\u7684\u51fd\u6570\u5c31\u662f\u901a\u7528\u51fd\u6570<\/p>\n<\/blockquote>\n<h3>4.1\u3001\u5e38\u89c1\u901a\u7528\u51fd\u6570<\/h3>\n<p>\u80fd\u591f\u63a5\u53d7\u4e00\u4e2a\u6570\u7ec4\u7684\u53eb\u505a\u4e00\u5143\u51fd\u6570\uff0c\u63a5\u53d7\u4e24\u4e2a\u6570\u7ec4\u7684\u53eb\u4e8c\u5143\u51fd\u6570\uff0c\u7ed3\u679c\u8fd4\u56de\u7684\u4e5f\u662f\u4e00\u4e2a\u6570\u7ec4<\/p>\n<ul>\n<li>\u4e00\u5143\u51fd\u6570\uff1a<\/li>\n<\/ul>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: center;\">\u51fd\u6570<\/th>\n<th style=\"text-align: center;\">\u529f\u80fd<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: center;\">abs\u3001fabs<\/td>\n<td style=\"text-align: center;\">\u5206\u522b\u662f\u8ba1\u7b97\u6574\u6570\u548c\u6d6e\u70b9\u6570\u7684\u7edd\u5bf9\u503c<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">sqrt<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u5404\u5143\u7d20\u7684\u5e73\u65b9\u6839<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">square<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u5404\u5143\u7d20\u7684\u5e73\u65b9<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">exp<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u5404\u5143\u7d20\u7684\u6307\u6570e**x<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">log<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u81ea\u7136\u5bf9\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">sign<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u5404\u5143\u7d20\u7684\u6b63\u8d1f\u53f7<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">ceil<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u5404\u5143\u7d20\u7684ceiling\u503c<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">floor<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u5404\u5143\u7d20floor\u503c\uff0c\u5373\u5c0f\u4e8e\u7b49\u4e8e\u8be5\u503c\u7684\u6700\u5927\u6574\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">rint<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u5404\u5143\u7d20\u7684\u503c\u56db\u820d\u4e94\u5165\u5230\u6700\u63a5\u8fd1\u7684\u6574\u6570\uff0c\u4fdd\u7559dtype<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">modf<\/td>\n<td style=\"text-align: center;\">\u5c06\u6570\u7ec4\u7684\u5c0f\u6570\u90e8\u5206\u548c\u6574\u6570\u90e8\u5206\u4ee5\u4e24\u4e2a\u72ec\u7acb\u6570\u7ec4\u7684\u5f62\u5f0f\u8fd4\u56de\uff0c\u4e0ePython\u7684divmod\u65b9\u6cd5\u7c7b\u4f3c<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">isnan<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u5404\u5143\u7d20\u7684\u6b63\u8d1f\u53f7<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">isinf<\/td>\n<td style=\"text-align: center;\">\u8868\u793a\u90a3\u4e9b\u5143\u7d20\u662f\u65e0\u7a77\u7684\u5e03\u5c14\u578b\u6570\u7ec4<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">cos\uff0csin\uff0ctan<\/td>\n<td style=\"text-align: center;\">\u666e\u901a\u578b\u548c\u53cc\u66f2\u578b\u4e09\u89d2\u51fd\u6570<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p>\u4ee5\u4e0b\u7b80\u5355\u6f14\u793a\u5e38\u7528\u7684\u51e0\u4e2a\u4e00\u5143\u51fd\u6570\uff1a<\/p>\n<pre><code class=\"language-python\"># \u8ba1\u7b97\u6574\u6570\u7edd\u5bf9\u503c\narr = np.random.randint(-10,10,20)\nnp.abs(arr)\n> array([9, 7, 3, 1, 5, 8, 7, 9, 4, 2, 7, 3, 4, 6, 6, 9, 2, 5, 8, 1])\n-------------------------------------------------------------------------------\n# \u8ba1\u7b97\u6d6e\u70b9\u6570\u7edd\u5bf9\u503c\narr = np.random.randn(2,5)\nnp.fabs(arr)\n> array([[0.09892302, 0.06200835, 1.0324653 , 1.58089607, 0.44506652],\n       [0.34897694, 1.04843539, 0.83976969, 0.4731551 , 0.92229931]])\n------------------------------------------------------------------------------\n# \u8ba1\u7b97\u5404\u5143\u7d20\u7684\u5e73\u65b9\u6839\narr = np.arange(10)\nnp.sqrt(arr)\n> array([0.        , 1.        , 1.41421356, 1.73205081, 2.        ,\n       2.23606798, 2.44948974, 2.64575131, 2.82842712, 3.        ])<\/code><\/pre>\n<ul>\n<li>\u4e8c\u5143\u51fd\u6570\uff1a<\/li>\n<\/ul>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: center;\">\u51fd\u6570<\/th>\n<th style=\"text-align: center;\">\u529f\u80fd<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: center;\">add<\/td>\n<td style=\"text-align: center;\">\u5c06\u6570\u7ec4\u4e2d\u5bf9\u5e94\u7684\u5143\u7d20\u76f8\u52a0<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">subtract<\/td>\n<td style=\"text-align: center;\">\u4ece\u7b2c\u4e00\u4e2a\u6570\u7ec4\u4e2d\u51cf\u53bb\u7b2c\u4e8c\u4e2a\u6570\u7ec4\u4e2d\u7684\u5143\u7d20<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">multiply<\/td>\n<td style=\"text-align: center;\">\u6570\u7ec4\u5143\u7d20\u76f8\u4e58<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">divide\u3001floor_divide<\/td>\n<td style=\"text-align: center;\">\u9664\u6cd5\u6216\u5411\u4e0b\u5706\u6574\u9664\u6cd5\uff08\u820d\u5f03\u4f59\u6570\uff09<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">power<\/td>\n<td style=\"text-align: center;\">\u5bf9\u7b2c\u4e00\u4e2a\u6570\u7ec4\u4e2d\u7684\u5143\u7d20A\uff0c\u6839\u636e\u7b2c\u4e8c\u4e2a\u6570\u7ec4\u4e2d\u7684\u76f8\u5e94\u5143\u7d20B\u8ba1\u7b97A**B<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">maximum\uff0cfmax<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u6700\u5927\u503c\uff0cfmax\u5ffd\u7565NAN<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">miximum\uff0cfmix<\/td>\n<td style=\"text-align: center;\">\u8ba1\u7b97\u6700\u5c0f\u503c\uff0cfmin\u5ffd\u7565NAN<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">mod<\/td>\n<td style=\"text-align: center;\">\u5143\u7d20\u7684\u6c42\u6a21\u8ba1\u7b97\uff08\u9664\u6cd5\u7684\u4f59\u6570\uff09<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<pre><code class=\"language-python\">arr = np.random.randint(0,10,5)\narr1 = np.random.randint(0,10,5)\narr,arr1\n> (array([0, 1, 8, 2, 6]), array([5, 4, 1, 7, 0]))\n-------------------------------------------------------------------------\n# add \u5c06\u6570\u7ec4\u4e2d\u5bf9\u5e94\u7684\u5143\u7d20\u76f8\u52a0\nnp.add(arr,arr1)\n> array([5, 5, 9, 9, 6])\n-------------------------------------------------------------------------\n# subtract \u4ece\u7b2c\u4e00\u4e2a\u6570\u7ec4\u4e2d\u51cf\u53bb\u7b2c\u4e8c\u4e2a\u6570\u7ec4\u4e2d\u7684\u5143\u7d20\nnp.subtract(arr,arr1)\n> array([-5, -3,  7, -5,  6])\n-------------------------------------------------------------------------\n# multiply \u6570\u7ec4\u5143\u7d20\u76f8\u4e58\nnp.multiply(arr,arr1)\n> array([ 0,  4,  8, 14,  0])\n-------------------------------------------------------------------------\n...<\/code><\/pre>\n<blockquote>\n<p>\u8865\u5145\u5185\u5bb9\uff1a\u6d6e\u70b9\u6570\u7279\u6b8a\u503c<\/p>\n<\/blockquote>\n<p>\u6d6e\u70b9\u6570\uff1afloat<br \/>\n\u6d6e\u70b9\u6570\u6709\u4e24\u4e2a\u7279\u6b8a\u503c\uff1a<\/p>\n<pre><code class=\"language-python\">1\u3001nan(Not a Number):\u4e0d\u7b49\u4e8e\u4efb\u4f55\u6d6e\u70b9\u6570\uff08nan != nan\uff09\n---------------------------------------------\n2\u3001inf(infinity):\u6bd4\u4efb\u4f55\u6d6e\u70b9\u6570\u90fd\u5927\n---------------------------------------------<\/code><\/pre>\n<ul>\n<li>Numpy\u4e2d\u521b\u5efa\u7279\u6b8a\u503c\uff1anp.nan\u3001np.inf<\/li>\n<li>\u6570\u636e\u5206\u6790\u4e2d\uff0cnan\u5e38\u88ab\u7528\u4f5c\u8868\u793a\u6570\u636e\u7f3a\u5931\u503c<\/li>\n<\/ul>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy8.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy8.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u4ee5\u4e0a\u51fd\u6570\u4f7f\u7528\u975e\u5e38\u65b9\u4fbf\uff0c\u4f7f\u7528\u8fd9\u4e9b\u65b9\u6cd5\u53ef\u4ee5\u8ba9\u6570\u636e\u5206\u6790\u7684\u64cd\u4f5c\u66f4\u52a0\u4fbf\u6377\u3002<\/p>\n<h3>4.2\u3001\u6570\u5b66\u7edf\u8ba1\u65b9\u6cd5<\/h3>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: center;\">\u51fd\u6570<\/th>\n<th style=\"text-align: center;\">\u529f\u80fd<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: center;\">sum<\/td>\n<td style=\"text-align: center;\">\u6c42\u548c<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">cumsum<\/td>\n<td style=\"text-align: center;\">\u6c42\u524d\u7f00\u548c<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">mean<\/td>\n<td style=\"text-align: center;\">\u6c42\u5e73\u5747\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">std<\/td>\n<td style=\"text-align: center;\">\u6c42\u6807\u51c6\u5dee<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">var<\/td>\n<td style=\"text-align: center;\">\u6c42\u65b9\u5dee<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">min<\/td>\n<td style=\"text-align: center;\">\u6c42\u6700\u5c0f\u503c<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">max<\/td>\n<td style=\"text-align: center;\">\u6c42\u6700\u5927\u503c<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">argmin<\/td>\n<td style=\"text-align: center;\">\u6c42\u6700\u5c0f\u503c\u7d22\u5f15<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">argmax<\/td>\n<td style=\"text-align: center;\">\u6c42\u6700\u5927\u503c\u7d22\u5f15<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<pre><code class=\"language-python\">arr = np.random.randint(0,10,10)\narr\n> array([2, 9, 6, 5, 4, 2, 9, 8, 0, 5])\n-------------------------------------------------------------------------\n# sum \u6c42\u548c\nnp.sum(arr)\n> 50\n-------------------------------------------------------------------------\n# cumsum \u6c42\u524d\u7f00\u548c\nnp.cumsum(arr)\narray([ 2, 11, 17, 22, 26, 28, 37, 45, 45, 50], dtype=int32) # \u4f9d\u6b21\u7d2f\u52a0\n-------------------------------------------------------------------------\n# mean \u6c42\u5e73\u5747\u6570\nnp.mean(arr)\n> 5.0\n-------------------------------------------------------------------------\n# \u7531\u4e8e\u6b64\u6863\u5185\u5bb9\u592a\u8fc7\u7b80\u5355\uff0c\u540e\u7eed\u5c31\u4e0d\u4e00\u4e00\u5c55\u793a\u4e86\n...<\/code><\/pre>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy9.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy9.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h3>4.3\u3001\u968f\u673a\u6570<\/h3>\n<p>\u6211\u4eec\u6709\u5b66\u8fc7python\u4e2d\u751f\u6210\u968f\u673a\u6570\u7684\u6a21\u5757random\uff0c\u5728numpy\u4e2d\u4e5f\u6709\u4e00\u4e2a\u968f\u673a\u6570\u751f\u6210\u51fd\u6570\uff0c\u5b83\u5728<strong><code>np.random<\/code><\/strong>\u7684\u5b50\u5305\u5f53\u4e2d\u3002\u5728Python\u81ea\u5e26\u7684random\u5f53\u4e2d\u53ea\u80fd\u751f\u6210\u4e00\u4e9b\u7b80\u5355\u3001\u57fa\u7840\u7684\u968f\u673a\u6570\uff0c\u800c\u5728np.random\u5f53\u4e2d\u662f\u53ef\u4ee5\u751f\u6210\u4e00\u4e9b\u9ad8\u7ea7\u7684\u968f\u673a\u6570\u7684\u3002np.random\u8981\u6bd4Python\u81ea\u5e26\u7684random\u5305\u66f4\u52a0\u7075\u6d3b\u3002<\/p>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: center;\">\u51fd\u6570<\/th>\n<th style=\"text-align: center;\">\u529f\u80fd<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: center;\">rand<\/td>\n<td style=\"text-align: center;\">\u8fd4\u56de\u7ed9\u5b9a\u7ef4\u5ea6\u7684\u968f\u673a\u6570\u7ec4\uff080\u52301\u4e4b\u95f4\u7684\u6570\uff09<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">randn<\/td>\n<td style=\"text-align: center;\">\u8fd4\u56de<strong>\u7ed9\u5b9a\u7ef4\u5ea6<\/strong>\u7684\u968f\u673a\u6570\u7ec4<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">randint<\/td>\n<td style=\"text-align: center;\">\u8fd4\u56de\u7ed9\u5b9a\u533a\u95f4\u7684\u968f\u673a\u6574\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">choice<\/td>\n<td style=\"text-align: center;\">\u7ed9\u5b9a\u7684\u4e00\u7ef4\u6570\u7ec4\u4e2d\u968f\u673a\u9009\u62e9<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">shuffle<\/td>\n<td style=\"text-align: center;\">\u539f\u5217\u8868\u4e0a\u5c06\u5143\u7d20\u6253\u4e71\uff08\u4e0erandom.shuffle\u76f8\u540c\uff09<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">uniform<\/td>\n<td style=\"text-align: center;\">\u7ed9\u5b9a\u5f62\u72b6\u4ea7\u751f\u968f\u673a\u6570\u7ec4<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">seed<\/td>\n<td style=\"text-align: center;\">\u8bbe\u5b9a\u968f\u673a\u79cd\u5b50\uff08\u4f7f\u76f8\u540c\u53c2\u6570\u751f\u6210\u7684\u968f\u673a\u6570\u76f8\u540c\uff09<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">standard_normal<\/td>\n<td style=\"text-align: center;\">\u751f\u6210\u6b63\u6001\u5206\u5e03\u7684\u968f\u673a\u6837\u672c\u6570<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<pre><code class=\"language-python\"># rand \u8fd4\u56de\u7ed9\u5b9a\u7ef4\u5ea6\u7684\u968f\u673a\u6570\u7ec4\nnp.random.rand(2,2,2)\n> array([[[0.37992696, 0.18115096],\n        [0.78854551, 0.05684808]],\n\n       [[0.69699724, 0.7786954 ],\n        [0.77740756, 0.25942256]]])\n-------------------------------------------------------------------------\n# randn \u8fd4\u56de\u7ed9\u5b9a\u7ef4\u5ea6\u7684\u968f\u673a\u6570\u7ec4\nnp.random.randn(2,4)\n> array([[ 0.76676877,  0.21752554,  2.08444169,  1.51347609],\n       [-2.10082473,  1.00607292, -1.03711487, -1.80526763]])\n-------------------------------------------------------------------------\n# randint \u8fd4\u56de\u7ed9\u5b9a\u533a\u95f4\u7684\u968f\u673a\u6574\u6570\nnp.random.randint(0,20)\n> 15\n-------------------------------------------------------------------------\n# chocie \u7ed9\u5b9a\u7684\u4e00\u7ef4\u6570\u7ec4\u4e2d\u968f\u673a\u9009\u62e9\nnp.random.choice(9,3)  # # \u4ecenp.range(9)\u4e2d\uff0c\uff08\u9ed8\u8ba4)\u6709\u653e\u56de\u5730\u7b49\u6982\u7387\u9009\u62e9\u4e09\u4e2a\u6570\n> array([5, 8, 2])\nnp.random.choice(9,3,replace=False)  # \u65e0\u653e\u56de\u5730\u9009\u62e9\n> array([1, 2, 0])\n------------------------------------------------------------------------\n# shuffle \u539f\u5217\u8868\u4e0a\u5c06\u5143\u7d20\u6253\u4e71\uff08\u4e0erandom.shuffle\u76f8\u540c\uff09\narr = np.arange(10)\nnp.random.shuffle(arr)\narr\n> array([4, 5, 0, 3, 7, 8, 9, 1, 2, 6])\n------------------------------------------------------------------------\n# uniform \u7ed9\u5b9a\u5f62\u72b6\u4ea7\u751f\u968f\u673a\u6570\u7ec4\nnp.random.uniform(0,1,[3,3,3])\n> array([[[0.80239474, 0.37170323, 0.5134832 ],\n        [0.42046889, 0.40245839, 0.0812019 ],\n        [0.8788738 , 0.48545176, 0.73723353]],\n\n       [[0.79057724, 0.80644632, 0.65966656],\n        [0.43833643, 0.53994887, 0.46762885],\n        [0.44472436, 0.08944074, 0.34148912]],\n\n       [[0.7042795 , 0.58397044, 0.13061102],\n        [0.22925123, 0.97745023, 0.14823085],\n        [0.6960559 , 0.07936633, 0.91221842]]])\n------------------------------------------------------------------------\n# seed \u8bbe\u5b9a\u968f\u673a\u79cd\u5b50\uff08\u4f7f\u76f8\u540c\u53c2\u6570\u751f\u6210\u7684\u968f\u673a\u6570\u76f8\u540c\uff09\nnp.random.seed(0)  # \u5f53seed(0)\u65f6\u751f\u6210\u4ee5\u4e0b\u968f\u673a\u6570\u7ec4\nnp.random.rand(5)\n> array([0.5488135 , 0.71518937, 0.60276338, 0.54488318, 0.4236548 ])\nnp.random.seed(2)  # send(5)\u65f6\u751f\u6210\u4ee5\u4e0b\u968f\u673a\u6570\u7ec4\nnp.random.rand(5)\n> array([0.5488135 , 0.71518937, 0.60276338, 0.54488318, 0.4236548 ])\nnp.random.seed(0)  # \u518d\u6b21\u4f7f\u7528send(0)\u4f1a\u53d1\u73b0\u8fd4\u56de\u6700\u5f00\u59cb\u7684\u968f\u673a\u6570\u7ec4\nnp.random.rand(5)\n> array([0.5488135 , 0.71518937, 0.60276338, 0.54488318, 0.4236548 ])\n------------------------------------------------------------------------\n# standard_normal \u751f\u6210\u6b63\u6001\u5206\u5e03\u7684\u968f\u673a\u6837\u672c\u6570\nnp.random.standard_normal([2,10])\n> array([[-0.17937969, -0.69277058,  1.13782687, -0.16915725, -0.76391367,\n        -0.4980731 , -0.36289111,  0.26396031, -0.62964191, -0.4722584 ],\n       [-1.51336104,  1.10762468,  0.17623875, -0.94035354,  0.92959433,\n        -1.06279492, -0.88640627,  1.92134696, -0.45978052, -1.08903444]])<\/code><\/pre>\n<blockquote>\n<p>np.random\u548cPython\u539f\u751f\u7684random\u7684\u533a\u522b\uff1a<\/p>\n<\/blockquote>\n<table>\n<thead>\n<tr>\n<th style=\"text-align: center;\">\u6bd4\u8f83\u5185\u5bb9<\/th>\n<th style=\"text-align: center;\"><strong>random<\/strong><\/th>\n<th style=\"text-align: center;\">np.random<\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td style=\"text-align: center;\">\u8f93\u5165\u7c7b\u578b<\/td>\n<td style=\"text-align: center;\">\u975e\u7a7a\u7684\u5217\u8868\u7c7b\u578b\uff08\u5305\u62ec\u5217\u8868\u3001\u5b57\u7b26\u4e32\u548c\u5143\u7ec4\uff09<\/td>\n<td style=\"text-align: center;\">\u975e\u7a7a\u7684\u5217\u8868\u7c7b\u578b\uff08\u5305\u62ec\u5217\u8868\u3001\u5b57\u7b26\u4e32\u548c\u5143\u7ec4\uff09+ numpy.array\u7c7b\u578b<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">\u8f93\u51fa\u7ef4\u5ea6<\/td>\n<td style=\"text-align: center;\">\u4e00\u4e2a\u6570\u6216\u4e00\u4e2alist\uff08\u591a\u4e2a\u6570\uff09<\/td>\n<td style=\"text-align: center;\">\u53ef\u6307\u5b9a\u590d\u6742\u7684size<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">\u6307\u5b9a(a,b)\u8303\u56f4<\/td>\n<td style=\"text-align: center;\">\u53ef\u4ee5<\/td>\n<td style=\"text-align: center;\">\u6574\u6570\u53ef\u6307\u5b9a\uff0c\u6d6e\u70b9\u6570\u4e0d\u884c\uff0c\u9700\u81ea\u884c\u8f6c\u6362<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">\u6279\u91cf\u8f93\u51fa<\/td>\n<td style=\"text-align: center;\">\u4e0d\u53ef<\/td>\n<td style=\"text-align: center;\">\u53ef\u3002\u901a\u8fc7\u6307\u5b9asize\u53c2\u6570<\/td>\n<\/tr>\n<tr>\n<td style=\"text-align: center;\">\u7279\u5b9a\u5206\u5e03<\/td>\n<td style=\"text-align: center;\">\u6db5\u76d6\u4e86\u5e38\u7528\u7684\u51e0\u4e2a\u5206\u5e03; \u53ea\u80fd\u5355\u4e2a\u8f93\u51fa<\/td>\n<td style=\"text-align: center;\">\u51e0\u4e4e\u6db5\u76d6\u4e86\u6240\u6709\u5206\u5e03\uff1b\u53ef\u6279\u91cf\u8f93\u51fa<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy10.gif'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/numpy10.gif\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u53ea\u8981\u80fd\u628a\u4ee5\u4e0a\u6240\u6709\u7684\u5185\u5bb9\u638c\u63e1\uff0c\u6570\u636e\u5206\u6790\u8fd9\u95e8\u529f\u592b\u4f60\u5c31\u7b97\u662f\u6253\u901a\u4e86\u4efb\u7763\u4e8c\u8109\u4e86\uff0c\u5b66\u8d77\u6765\u8f7b\u677e\u53c8\u6109\u5feb\u3002<\/p>\n<h2>5\u3001\u6570\u636e\u8868\u793a<\/h2>\n<p>\u6240\u6709\u9700\u8981\u5904\u7406\u548c\u6784\u5efa\u6a21\u578b\u6240\u9700\u7684\u6570\u636e\u7c7b\u578b\uff08\u7535\u5b50\u8868\u683c\u3001\u56fe\u50cf\u3001\u97f3\u9891\u7b49\uff09\uff0c\u5176\u4e2d\u5f88\u591a\u90fd\u9002\u5408\u5728 n \u7ef4\u6570\u7ec4\u4e2d\u8868\u793a\uff1a<\/p>\n<blockquote>\n<p>\u8868\u683c\u548c\u7535\u5b50\u8868\u683c<\/p>\n<\/blockquote>\n<p>\u8868\u683c\u548c\u7535\u5b50\u8868\u683c\u662f\u4e8c\u7ef4\u77e9\u9635\u3002\u7535\u5b50\u8868\u683c\u4e2d\u7684\u6bcf\u4e2a\u5de5\u4f5c\u8868\u90fd\u53ef\u4ee5\u662f\u5b83\u81ea\u5df1\u7684\u53d8\u91cf\u3002python \u4e2d\u6700\u6d41\u884c\u7684\u62bd\u8c61\u662f pandas \u6570\u636e\u5e27\uff0c\u5b83\u5b9e\u9645\u4e0a\u4f7f\u7528\u4e86 NumPy \u5e76\u5728\u5176\u4e4b\u4e0a\u6784\u5efa\u3002<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u8868\u683c.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u8868\u683c.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<blockquote>\n<p>\u97f3\u9891\u548c\u65f6\u95f4\u5e8f\u5217<\/p>\n<\/blockquote>\n<p>\u97f3\u9891\u6587\u4ef6\u662f\u6837\u672c\u7684\u4e00\u7ef4\u6570\u7ec4\u3002\u6bcf\u4e2a\u6837\u672c\u90fd\u662f\u4e00\u4e2a\u6570\u5b57\uff0c\u4ee3\u8868\u97f3\u9891\u4fe1\u53f7\u7684\u4e00\u5c0f\u90e8\u5206\u3002CD \u8d28\u91cf\u7684\u97f3\u9891\u6bcf\u79d2\u5305\u542b 44,100 \u4e2a\u6837\u672c\uff0c\u6bcf\u4e2a\u6837\u672c\u662f-65535 \u5230 65536 \u4e4b\u95f4\u7684\u6574\u6570\u3002\u8fd9\u610f\u5473\u7740\u5982\u679c\u4f60\u6709\u4e00\u4e2a 10 \u79d2\u7684 CD \u8d28\u91cf WAVE \u6587\u4ef6\uff0c\u4f60\u53ef\u4ee5\u5c06\u5b83\u52a0\u8f7d\u5230\u957f\u5ea6\u4e3a 10 * 44,100 = 441,000 \u7684 NumPy \u6570\u7ec4\u4e2d\u3002\u5982\u679c\u60f3\u8981\u63d0\u53d6\u97f3\u9891\u7684\u7b2c\u4e00\u79d2\uff0c\u53ea\u9700\u5c06\u6587\u4ef6\u52a0\u8f7d\u5230 audio \u7684 NumPy \u6570\u7ec4\u4e2d\uff0c\u7136\u540e\u83b7\u53d6 audio[:44100]\u3002<\/p>\n<p>\u4ee5\u4e0b\u662f\u4e00\u6bb5\u97f3\u9891\u6587\u4ef6\uff1a<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u97f3\u9891.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u97f3\u9891.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u65f6\u95f4\u5e8f\u5217\u6570\u636e\u4e5f\u662f\u5982\u6b64\uff08\u5982\u80a1\u7968\u4ef7\u683c\u968f\u65f6\u95f4\u53d8\u5316\uff09\u3002<\/p>\n<blockquote>\n<p>\u56fe\u50cf<\/p>\n<\/blockquote>\n<p>\u56fe\u50cf\u662f\u5c3a\u5bf8\uff08\u9ad8\u5ea6 x \u5bbd\u5ea6\uff09\u7684\u50cf\u7d20\u77e9\u9635\u3002<\/p>\n<p>\u5982\u679c\u56fe\u50cf\u662f\u9ed1\u767d\uff08\u5373\u7070\u5ea6\uff09\u7684\uff0c\u5219\u6bcf\u4e2a\u50cf\u7d20\u90fd\u53ef\u4ee5\u7528\u5355\u4e2a\u6570\u5b57\u8868\u793a\uff08\u901a\u5e38\u5728 0\uff08\u9ed1\u8272\uff09\u548c 255\uff08\u767d\u8272\uff09\u4e4b\u95f4\uff09\u3002\u60f3\u8981\u88c1\u526a\u56fe\u50cf\u5de6\u4e0a\u89d2 10 x 10 \u7684\u50cf\u7d20\u5417\uff1f\u5728 NumPy \u5199\u5165\u5373\u53ef\u3002<\/p>\n<p>\u4e0b\u56fe\u662f\u4e00\u4e2a\u56fe\u50cf\u6587\u4ef6\u7684\u7247\u6bb5\uff1a<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u56fe\u50cf01.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u56fe\u50cf01.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<p>\u5982\u679c\u56fe\u50cf\u662f\u5f69\u8272\u7684\uff0c\u5219\u6bcf\u4e2a\u50cf\u7d20\u7531\u4e09\u4e2a\u6570\u5b57\u8868\u793a\u2014\u2014\u7ea2\u8272\u3001\u7eff\u8272\u548c\u84dd\u8272\u3002\u5728\u8fd9\u79cd\u60c5\u51b5\u4e0b\uff0c\u6211\u4eec\u9700\u8981\u4e00\u4e2a\u4e09\u7ef4\u6570\u7ec4\uff08\u56e0\u4e3a\u6bcf\u4e2a\u5355\u5143\u683c\u53ea\u80fd\u5305\u542b\u4e00\u4e2a\u6570\u5b57\uff09\u3002\u56e0\u6b64\u5f69\u8272\u56fe\u50cf\u7531\u5c3a\u5bf8\u4e3a\uff08\u9ad8 x \u5bbd x3\uff09\u7684 ndarray \u8868\u793a\uff1a<\/p>\n<p><div class='fancybox-wrapper lazyload-container-unload' data-fancybox='post-images' href='https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u56fe\u50cf02.jpg'><img class=\"lazyload lazyload-style-2\" src=\"data:image\/svg+xml;base64,PCEtLUFyZ29uTG9hZGluZy0tPgo8c3ZnIHdpZHRoPSIxIiBoZWlnaHQ9IjEiIHhtbG5zPSJodHRwOi8vd3d3LnczLm9yZy8yMDAwL3N2ZyIgc3Ryb2tlPSIjZmZmZmZmMDAiPjxnPjwvZz4KPC9zdmc+\"  data-original=\"https:\/\/egonlin.com\/wp-content\/uploads\/2022\/03\/np\u56fe\u50cf02.jpg\" src=\"data:image\/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAYAAAAfFcSJAAAAAXNSR0IArs4c6QAAAARnQU1BAACxjwv8YQUAAAAJcEhZcwAADsQAAA7EAZUrDhsAAAANSURBVBhXYzh8+PB\/AAffA0nNPuCLAAAAAElFTkSuQmCC\" alt=\"\" \/><\/div><\/p>\n<h2>6\u3001\u603b\u7ed3<\/h2>\n<p>\u4f7f\u7528numpy\uff0c\u53ef\u4ee5\u4e3a\u6211\u4eec\u63d0\u4f9b\u4e00\u7ec4\u4e30\u5bcc\u800c\u53c8\u7075\u6d3b\u7684\u6570\u636e\u7ed3\u6784\uff0c\u4ee5\u91d1\u878d\u7684\u89d2\u5ea6\u6765\u770b\u7684\u8bdd\u4e0b\u9762\u51e0\u79cd\u7c7b\u578b\u662f\u6700\u91cd\u8981\u7684\uff1a<\/p>\n<blockquote>\n<p>\u57fa\u672c\u6570\u636e\u7c7b\u578b<\/p>\n<\/blockquote>\n<p>\u200b   \u5728\u91d1\u878d\u91cf\u5316\u5f53\u4e2d\uff0c\u6574\u6570\u3001\u6d6e\u70b9\u6570\u548c\u5b57\u7b26\u4e32\u7ed9\u6211\u4eec\u63d0\u4f9b\u4e86\u539f\u5b50\u6570\u636e\u7c7b\u578b<\/p>\n<blockquote>\n<p>\u6807\u51c6\u6570\u636e\u7ed3\u6784<\/p>\n<\/blockquote>\n<p>\u200b   \u5143\u7ec4\u3001\u5217\u8868\u3001\u5b57\u5178\u548c\u96c6\u5408\uff0c\u8fd9\u4e9b\u5728\u91d1\u878d\u5f53\u4e2d\u6709\u8bb8\u591a\u5e94\u7528\u9886\u57df\uff0c\u5217\u8868\u901a\u5e38\u662f\u6700\u4e3a\u5e38\u7528\u7684<\/p>\n<blockquote>\n<p>\u6570\u7ec4<\/p>\n<\/blockquote>\n<p>\u200b   \u8bf4\u5230\u6570\u7ec4\u80af\u5b9a\u5c31\u662f\u4eca\u5929\u6240\u5b66\u4e60\u7684numpy\u4e2d\u7684ndarray\u6570\u7ec4\uff0c\u5b83\u5bf9\u4e8e\u6570\u636e\u7684\u5904\u7406\u6027\u80fd\u66f4\u9ad8\uff0c\u4ee3\u7801\u66f4\u7b80\u6d01\u3001\u65b9\u4fbf<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Numpy \u4ec0\u4e48\u662fnumpy \u4e3a\u4ec0\u4e48\u8981\u7528numpy \u600e\u4e48\u7528numpy \u4e3a\u4ec0\u4e48\u8981\u7528ndarray ndarray [&hellip;]<\/p>\n","protected":false},"author":3,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[313,310],"tags":[],"_links":{"self":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/3601"}],"collection":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/users\/3"}],"replies":[{"embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3601"}],"version-history":[{"count":0,"href":"https:\/\/egonlin.com\/index.php?rest_route=\/wp\/v2\/posts\/3601\/revisions"}],"wp:attachment":[{"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3601"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3601"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/egonlin.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3601"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}