{"id":189,"date":"2019-03-27T13:24:28","date_gmt":"2019-03-27T05:24:28","guid":{"rendered":"http:\/\/fankasy.xyz\/?p=189"},"modified":"2019-03-27T13:32:35","modified_gmt":"2019-03-27T05:32:35","slug":"%e8%ae%a1%e7%ae%97%e6%9c%ba%e7%bb%84%e6%88%90%e5%8e%9f%e7%90%86-%e6%b5%ae%e7%82%b9%e6%95%b0%e8%a1%a8%e7%a4%ba","status":"publish","type":"post","link":"http:\/\/fankasy.xyz\/index.php\/2019\/03\/27\/%e8%ae%a1%e7%ae%97%e6%9c%ba%e7%bb%84%e6%88%90%e5%8e%9f%e7%90%86-%e6%b5%ae%e7%82%b9%e6%95%b0%e8%a1%a8%e7%a4%ba\/","title":{"rendered":"\u8ba1\u7b97\u673a\u7ec4\u6210\u539f\u7406–\u6d6e\u70b9\u6570\u8868\u793a"},"content":{"rendered":"

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\u540c\u6837\u7684\u6570\u503c\u53ef\u4ee5\u6709\u591a\u79cd\u6d6e\u70b9\u6570\u8868\u8fbe\u65b9\u5f0f\uff0c\u6bd4\u5982 101.11 \u53ef\u4ee5\u8868\u8fbe\u4e3a 10.111 \u00d7 10^1\uff0c0.10111 \u00d7 10^3 \u6216\u8005 1.0111 \u00d7 10^2\u3002\u56e0\u4e3a\u8fd9\u79cd\u591a\u6837\u6027\uff0c\u6709\u5fc5\u8981\u5bf9\u5176\u52a0\u4ee5\u89c4\u8303\u5316\u4ee5\u8fbe\u5230\u7edf\u4e00\u8868\u8fbe\u7684\u76ee\u6807\u3002\u505a\u51fa\u7684\u89c4\u5b9a\u5373\u662f\u6574\u6570\u4f4d\u4ec5\u4fdd\u7559\u4e00\u4e2a\u6570\u5b57\uff0c\u540c\u65f6\u56e0\u4e3a\u8fd9\u4e2a\u6570\u5b57\u4e00\u5b9a\u662f1\uff08\u4e0d\u662f1\u8bf4\u660e\u5c0f\u6570\u70b9\u79fb\u8fc7\u5934\u4e86\uff09\uff0c\u4e5f\u53ef\u4ee5\u7701\u7565\u6389\u3002\u663e\u7136\uff0c\u5c3e\u6570\u8d8a\u957f\u7cbe\u5ea6\u548c\u8868\u793a\u8303\u56f4\u5c31\u8d8a\u9ad8\u3002\u8d85\u51fa\u8303\u56f4\u65f6\u4f1a\u4ea7\u751f\u6ea2\u51fa\uff08Flow\uff09\uff0c\u4e00\u822c\u79f0\u5927\u4e8e\u7edd\u5bf9\u503c\u6700\u5927\u7684\u6570\u636e\u4e3a\u4e0a\u6ea2\uff0c\u5c0f\u4e8e\u7edd\u5bf9\u503c\u6700\u5c0f\u7684\u6570\u636e\u4e3a\u4e0b\u6ea2\uff0c\u5206\u522b\u4f1a\u88ab\u8ba4\u5b9a\u4e3a\u65e0\u7a77\u548c\u96f6\u3002<\/p>\n
\u3000\u3000IEEE754\u6807\u51c6\u89c4\u5b9a\u4e00\u4e2a\u5b9e\u6570V\u53ef\u4ee5\u7528:\u3000\u3000V\uff1d(\uff0d1)s\u00d7M\u00d72^E\u7684\u5f62\u5f0f\u8868\u793a\uff0c\u8bf4\u660e\u5982\u4e0b\uff1a\r\n\u3000\u3000(1)\u7b26\u53f7s(sign)\u51b3\u5b9a\u5b9e\u6570\u662f\u6b63\u6570(s\uff1d0)\u8fd8\u662f\u8d1f\u6570(s\uff1d1)\uff0c\u5bf9\u6570\u503c0\u7684\u7b26\u53f7\u4f4d\u7279\u6b8a\u5904\u7406\u3002\r\n\u3000\u3000(2)\u6709\u6548\u6570\u5b57M\u662f\u4e8c\u8fdb\u5236\u5c0f\u6570\uff0cM\u7684\u53d6\u503c\u8303\u56f4\u57281\u2264M\uff1c2\u62160\u2264M\uff1c1\u3002\r\n\u3000\u3000(3)\u6307\u6570E\uff08exponent\uff09\u662f\u7528\u79fb\u7801\u8868\u793a\u76842\u7684\u5e42\uff0c\u5b83\u7684\u4f5c\u7528\u662f\u5bf9\u6d6e\u70b9\u6570\u52a0\u6743\u3002<\/pre>\n
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\u975e\u89c4\u8303\u6570\u662f\u5565\uff1f\u5c31\u662f\u5f53\u6211\u4eec\u9047\u5230\u4e86\u7279\u522b\u5c0f\u7684\u6570\u5b57\uff0c\u5c0f\u5230\u6307\u6570\u7528\u5b8c\u4e86\u90fd\u8868\u793a\u4e0d\u51fa\u6765\u3002 \u6bd4\u59820.0001 \u00d7 2-125\uff0c\u8868\u8fbe\u4e3a\u89c4\u8303\u6d6e\u70b9\u6570\u5219\u4e3a 1.0 \u00d7 2-129\uff0c\u8d85\u8fc7\u4e862^-126\u7684\u9650\u5236\u3002\u4e3a\u4e86\u89e3\u51b3\u6b64\u7c7b\u95ee\u9898\uff0cIEEE \u6807\u51c6\u4e2d\u5f15\u5165\u4e86\u975e\u89c4\u8303\u6d6e\u70b9\u6570\u3002\u89c4\u5b9a\u5f53\u6d6e\u70b9\u6570\u7684\u6307\u6570\u4e3a\u5141\u8bb8\u7684\u6700\u5c0f\u6307\u6570\u503c\uff0c\u5c3e\u6570\u4e0d\u5fc5\u662f\u89c4\u8303\u5316\u7684\u3002\u6bd4\u5982\u4e0a\u9762\u4f8b\u5b50\u4e2d\u7684\u5dee\u503c\u53ef\u4ee5\u8868\u8fbe\u4e3a\u975e\u89c4\u8303\u7684\u6d6e\u70b9\u6570 0.001 \u00d7 2-126\u3002<\/p>\n
\u5f88\u591a\u5c0f\u6570\u6839\u672c\u65e0\u6cd5\u5728\u4e8c\u8fdb\u5236\u8ba1\u7b97\u673a\u4e2d\u7cbe\u786e\u8868\u793a\uff08\u6bd4\u5982\u6700\u7b80\u5355\u7684 0.1\uff09\u7531\u4e8e\u6d6e\u70b9\u6570\u5c3e\u6570\u57df\u7684\u4f4d\u6570\u662f\u6709\u9650\u7684\uff0c\u4e3a\u6b64\uff0c\u6d6e\u70b9\u6570\u7684\u5904\u7406\u529e\u6cd5\u662f\u6301\u7eed\u8be5\u8fc7\u7a0b\u76f4\u5230\u7531\u6b64\u5f97\u5230\u7684\u5c3e\u6570\u8db3\u4ee5\u586b\u6ee1\u5c3e\u6570\u57df\uff0c\u4e4b\u540e\u5bf9\u591a\u4f59\u7684\u4f4d\u8fdb\u884c\u820d\u5165\u3002\u4e8b\u5b9e\u4e0a\uff0c\u53ea\u6709\u5f88\u5c11\u4e00\u90e8\u5206\u5341\u8fdb\u5236\u5c0f\u6570\u5177\u6709\u7cbe\u786e\u7684\u4e8c\u8fdb\u5236\u6d6e\u70b9\u6570\u8868\u8fbe\u3002\u518d\u52a0\u4e0a\u6d6e\u70b9\u6570\u8fd0\u7b97\u8fc7\u7a0b\u4e2d\u7684\u8bef\u5dee\u7d2f\u79ef\uff0c\u7ed3\u679c\u662f\u5f88\u591a\u6211\u4eec\u770b\u6765\u975e\u5e38\u7b80\u5355\u7684\u5341\u8fdb\u5236\u8fd0\u7b97\u5728\u8ba1\u7b97\u673a\u4e0a\u5374\u5f80\u5f80\u51fa\u4eba\u610f\u6599\u3002\u8fd9\u5c31\u662f\u6700\u5e38\u89c1\u7684\u6d6e\u70b9\u8fd0\u7b97\u7684”\u4e0d\u51c6\u786e”\u95ee\u9898\u3002<\/p>\n
\u5bf9\u4e8e\u5355\u7cbe\u5ea6\u6570\uff0c\u7531\u4e8e\u6211\u4eec\u53ea\u6709 24 \u4f4d\u7684\u5c3e\u6570\uff08\u5176\u4e2d\u4e00\u4f4d\u9690\u85cf\uff09\uff0c\u6240\u4ee5\u53ef\u4ee5\u8868\u8fbe\u7684\u6700\u5927\u6307\u6570\u4e3a 2^24 – 1 = 16,777,215\u3002\uff08\u7279\u522b\u7684\uff0c16,777,216 \u662f\u5076\u6570\uff0c\u6240\u4ee5\u6211\u4eec\u53ef\u4ee5\u901a\u8fc7\u5c06\u5b83\u9664\u4ee5 2 \u5e76\u76f8\u5e94\u5730\u8c03\u6574\u6307\u6570\u6765\u4fdd\u5b58\u8fd9\u4e2a\u6570\uff0c\u8fd9\u6837 16,777,216 \u540c\u6837\u53ef\u4ee5\u88ab\u7cbe\u786e\u7684\u4fdd\u5b58\u3002\uff09\u56e0\u6b64\u4e00\u4e9b\u8d85\u8fc72^24\u7684int\u578b\u6570\u5c06\u65e0\u6cd5\u88ab\u8f6c\u6362\u6210float\u578b\uff08\u4f46\u5176\u5c3e\u90e8\u5168\u662f0\u65f6\u662f\u4f8b\u5916\uff09\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
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