{"published":"2019-07-28 00:00:00","title":"nan(\"is Not-a-Number\")","html":"<iframe src=\"https://hatenablog-parts.com/embed?url=https%3A%2F%2Fyohhoy.hatenadiary.jp%2Fentry%2F20190728%2Fp1\" title=\"nan(&quot;is Not-a-Number&quot;) - yohhoy\u306e\u65e5\u8a18\" class=\"embed-card embed-blogcard\" scrolling=\"no\" frameborder=\"0\" style=\"display: block; width: 100%; height: 190px; max-width: 500px; margin: 10px 0px;\"></iframe>","provider_url":"https://hatena.blog","author_name":"yohhoy","description":"\u30d7\u30ed\u30b0\u30e9\u30df\u30f3\u30b0\u8a00\u8a9eC/C++\u306b\u304a\u3051\u308b\u6d6e\u52d5\u5c0f\u6570\u70b9\u6570 NaN(Not-a-Number)*1 \u306b\u3064\u3044\u3066\u3002C/C++\u6a19\u6e96\u30e9\u30a4\u30d6\u30e9\u30ea\u306fquiet NaN*2\u3092\u8fd4\u3059nan\u95a2\u6570\u3092\u63d0\u4f9b\u3057\u3001\u540c\u95a2\u6570\u3067\u306f\u51e6\u7406\u7cfb\u5b9a\u7fa9(implementation-defined)\u306e\u30bf\u30b0\u6587\u5b57\u5217\u3092\u53d7\u3051\u53d6\u308b\u3002\u4e00\u822c\u7684\u306b\u306f\u7a7a\u6587\u5b57\u5217\"\"\u3092\u6307\u5b9a\u3059\u308b\u304c\u3001\u30e9\u30a4\u30d6\u30e9\u30ea\u4ed5\u69d8\u4e0a\u306f\u4efb\u610f\u306e\u6587\u5b57\u5217*3\u3092\u6307\u5b9a\u53ef\u80fd\u3002 // C #include <math.h> double d1 = nan(\"42\"); // OK double d2 = nan(\"wtf\"); // OK // C++ #include <cmath> double d1 = std::na\u2026","blog_title":"yohhoy\u306e\u65e5\u8a18","version":"1.0","blog_url":"https://yohhoy.hatenadiary.jp/","author_url":"https://blog.hatena.ne.jp/yohhoy/","height":"190","url":"https://yohhoy.hatenadiary.jp/entry/20190728/p1","type":"rich","image_url":null,"width":"100%","categories":["C","C++"],"provider_name":"Hatena Blog"}