![\"1.M*2^E\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094941-6a9d373510e10.png\")
——–>\u8fd9\u53ea\u662f\u903b\u8f91\u5f0f，\u5b9e\u9645\u5b58\u50a8\u4e0d\u540c)<\/span><\/li>\n\u603b\u4f4d\u6570：1+8+23 = 32bit<\/p>\n
64 \u4f4d double（\u53cc\u7cbe\u5ea6）：<\/p>\n
\u5173\u952e\u77e5\u8bc6\u70b9<\/p>\n
- \n
- float：23 \u4f4d\u5c3e\u6570，\u6362\u7b97\u5341\u8fdb\u5236\u5927\u7ea6 6~7 \u4f4d\u6709\u6548\u6570\u5b57<\/li>\n
- double：52 \u4f4d\u5c3e\u6570，\u5927\u7ea6 15~16 \u4f4d\u6709\u6548\u6570\u5b57<\/li>\n<\/ul>\n
\u8fd9\u5c31\u89e3\u91ca\u4e86\u4f60\u4e0a\u4e00\u9898：\u6570\u503c\u53d8\u5927\u4e4b\u540e，float \u5c3e\u90e8\u5c0f\u6570\u4e22\u5931\u7cbe\u5ea6\u3002<\/p>\n
- \u2757\u5341\u8fdb\u5236\u5c0f\u6570，\u5f88\u591a\u4e0d\u80fd\u7528\u4e8c\u8fdb\u5236\u6d6e\u70b9\u6570\u7cbe\u786e\u8868\u8fbe \u4f8b\u59820.1，\u5185\u5b58\u91cc\u9762\u662f\u65e0\u9650\u5faa\u73af\u4e8c\u8fdb\u5236\u5c0f\u6570，\u53ea\u80fd\u8fd1\u4f3c\u4fdd\u5b58，\u5b58\u5728\u5fae\u5c0f\u8bef\u5dee\u3002<\/li>\n
c<\/p>\n
#include <cstdio>
\nint main(void)
\n{
\n float f = 0.1f;
\n if(f == 0.1)
\n {
\n printf("\u76f8\u7b49");
\n }
\n else
\n {
\n printf("\u4e0d\u76f8\u7b49");
\n }
\n return 0;
\n}<\/p>\n\u8fd9\u6bb5\u4ee3\u7801\u8fd0\u884c\u8f93\u51fa：\u4e0d\u76f8\u7b49，0.1 float \u548c 0.1 (double) \u8fd1\u4f3c\u503c\u4e0d\u4e00\u6837\u3002<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094941-6a9d373519356.png\")
<\/p>\n
\n\u601d\u8003\u9898<\/p>\n
- float \u4e00\u5171 32bit，\u7b26\u53f7\u4f4d\u5360 1bit，\u9636\u7801\u5360\u591a\u5c11 bit？\u5c3e\u6570\u5360\u591a\u5c11 bit？<\/li>\n
- float \u7684\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57\u5927\u7ea6\u662f\u591a\u5c11\u4f4d？double \u5462？<\/li>\n
- \u5224\u65ad：0.1\u53ef\u4ee5\u5728 float \u4e2d\u88ab\u5b8c\u5168\u7cbe\u786e\u5b58\u50a8（\u5bf9 \/ \u9519）<\/li>\n
：<\/span><\/p>\n
1.8 23<\/span><\/p>\n
2.6~7 <\/span><\/p>\n
3.\u9519<\/span><\/p>\n
\u6574\u6570\u4f4d\u4e3a\u4ec0\u4e48\u4e0d\u662f1\u5c31\u662f0?\u4e3a\u4ec0\u4e48\u53ef\u4ee5\u9690\u85cf\u6574\u6570\u4f4d\u7f6e？<\/span><\/p>\n
：<\/span><\/p>\n
\u6279\u6539<\/p>\n
- float \u9636\u78018bit，\u5c3e\u657023bit \u2714（\u7b26\u53f7\u4f4d 1bit）<\/li>\n
- float：6\u20117 \u4f4d\u6709\u6548\u6570\u5b57；double：15\u201116 \u4f4d \u2714<\/li>\n
- \u9519 \u2714，0.1 \u662f\u5341\u8fdb\u5236\u5c0f\u6570，\u4e8c\u8fdb\u5236\u4e0b\u662f\u65e0\u9650\u5faa\u73af\u5c0f\u6570，\u53ea\u80fd\u8fd1\u4f3c\u5b58\u50a8\u3002<\/li>\n
\n\u4e3a\u4f55\u89c4\u683c\u5316\u6d6e\u70b9\u6570\u6574\u6570\u4f4d\u53ea\u80fd\u662f 1<\/h3>\n
IEEE\u2011754 \u89c4\u683c\u5316\u6d6e\u70b9\u6570，\u8981\u6c42\u4e8c\u8fdb\u5236\u79d1\u5b66\u8ba1\u6570\u6cd5\u5f3a\u5236\u5199\u6210：
![\"1.M*2^](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094942-6a9d373617b1b.png\")
<\/p>\n\u4e8c\u8fdb\u5236\u79d1\u5b66\u8ba1\u6570\u6cd5，\u5c0f\u6570\u70b9\u5de6\u8fb9\u53ea\u80fd\u662f 1，\u4e0d\u80fd\u662f 0，\u4e5f\u4e0d\u80fd\u662f 2\u3002<\/p>\n
\u4e8c\u8fdb\u5236\u6570\u5b57\u7279\u70b9<\/h4>\n
\u4e8c\u8fdb\u5236\u6bcf\u4e00\u4f4d\u53ea\u6709\u4e24\u79cd\u53d6\u503c：0\u30011\u3002<\/p>\n
- \n
- \u5982\u679c\u6574\u6570\u4f4d\u51990：0.101 \u00d7 2^3，\u8fd9\u4e2a\u53ef\u4ee5\u6539\u5199\u4e3a 1.01 \u00d7 2^2<\/li>\n<\/ul>\n
\u628a\u5c0f\u6570\u70b9\u5411\u53f3\u632a\u4e00\u4f4d，\u6307\u6570\u51cf 1，\u6574\u6570\u4f4d\u5c31\u53d8\u6210 1\u3002<\/p>\n
👉\u89c4\u683c\u5316\u7684\u5b9a\u4e49：\u628a\u6570\u5b57\u8c03\u6574\u6210\u300c\u6574\u6570\u90e8\u5206\u4e25\u683c\u7b49\u4e8e 1\u300d\u7684\u5f62\u5f0f\u3002 \u6240\u4ee5\u89c4\u683c\u5316\u6570\u6574\u6570\u4f4d\u6c38\u8fdc\u56fa\u5b9a\u4e3a1，\u4e0d\u4f1a\u51fa\u73b0 0\u30012 \u4e4b\u7c7b\u3002<\/p>\n
\u65e2\u7136\u6c38\u8fdc\u56fa\u5b9a\u662f1，\u8ba1\u7b97\u673a\u5c31\u4e0d\u9700\u8981\u628a\u8fd9\u4e2a 1 \u5b58\u5165\u5185\u5b58，\u76f4\u63a5\u7701\u7565，\u53ea\u5b58\u5c0f\u6570\u70b9\u540e\u9762 M\u3002 \u8fd9\u5c31\u662f\u90a3\u4e2a\u9690\u85cf\u4f4d 1\u7684\u6765\u6e90，\u51ed\u7a7a\u591a\u51fa\u6765\u4e00\u4f4d\u7cbe\u5ea6\u3002<\/p>\n
\n\u90a3\u4ec0\u4e48\u65f6\u5019\u6574\u6570\u4f4d\u53ef\u4ee5\u662f 0？<\/p>\n
\u53ea\u6709\u975e\u89c4\u683c\u5316\u6570（\u9636\u7801\u5168\u90e8 bit \u4e3a 0）\u3002 \u6b64\u65f6\u4e0d\u518d\u5f3a\u5236\u8981\u6c42\u6574\u6570\u4f4d\u4e3a 1<\/p>\n
\u683c\u5f0f\u53d8\u6210：
![\"0.M*2^{-126}\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094942-6a9d37361e455.png\")
<\/p>\n\u7528\u9014：\u8868\u793a\u65e0\u9650\u63a5\u8fd1 0 \u7684\u6781\u5c0f\u6570\u5b57\u3002<\/p>\n
\u7b80\u5355\u603b\u7ed3：<\/p>\n
- \u2705\u666e\u901a\u6b63\u5e38\u6d6e\u70b9\u6570（\u89c4\u683c\u5316）：\u6574\u6570\u4f4d\u56fa\u5b9a\u4e8c\u8fdb\u52361，\u9690\u85cf，\u4e0d\u5360\u5185\u5b58\u3002<\/li>\n
- \u2705\u9636\u7801\u5168 0（\u975e\u89c4\u683c\u5316）：\u6574\u6570\u4f4d\u662f0，\u4e0d\u518d\u9690\u85cf\u3002<\/li>\n
\u4e3e\u4e2a\u4f8b\u5b50<\/p>\n
\u5341\u8fdb\u5236 5.0<\/p>\n
\u5341\u8fdb\u5236 5 \u2192\u4e8c\u8fdb\u5236 101.0<\/p>\n
\u79d1\u5b66\u8ba1\u6570\u6cd5\u6539\u5199：
![\"1.010*2^2\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094942-6a9d3736247af.png\")
<\/p>\n\u6574\u6570\u90e8\u5206\u662f1，\u5185\u5b58\u53ea\u5b58\u5c0f\u6570\u70b9\u540e010\u3002<\/p>\n
：<\/span><\/p>\n
\u6709\u6548\u6570\u5b57\u662f\u600e\u4e48\u7b97\u51fa\u6765\u7684？<\/span><\/p>\n
：<\/span><\/p>\n
float 23bit \u5c3e\u6570，\u4e3a\u4ec0\u4e48\u5f97\u5230\u5927\u7ea6 7 \u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57<\/h3>\n
\u89c4\u683c\u5316 float \u5b9e\u9645\u5c3e\u6570：23bit \u5185\u5b58\u5b58\u50a8 M + \u786c\u4ef6\u9690\u85cf\u7684 1bit = 24bit \u6709\u6548\u4e8c\u8fdb\u5236\u4f4d\u3002<\/p>\n
\u95ee\u9898\u8f6c\u5316：24 \u4f4d\u4e8c\u8fdb\u5236，\u7b49\u4ef7\u591a\u5c11\u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57？<\/p>\n
\u516c\u5f0f：<\/p>\n
\u4f4d\u6570（\u5341\u8fdb\u5236） \u2248 \u4e8c\u8fdb\u5236\u4f4d\u6570 \u00d7\u00a0
![\"\\\\log_{10}2\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094942-6a9d37362abe5.png\")
<\/p>\n\u00a0\u2248\u00a0 \u00a00.3010<\/p>\n\u4ee3\u5165： 24 *\u00a0 0.3010\u00a0 \u00a0\u7ea6\u7b49\u4e8e\u00a0 \u00a07.44<\/p>\n
👉\u6240\u4ee5 float \u5927\u7ea6 6\u20117 \u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57\u3002<\/p>\n
\u540c\u7406 double： \u5c3e\u6570\u5185\u5b58 52bit，\u52a0\u4e0a\u9690\u85cf 1bit，\u4e00\u5171 53bit \u4e8c\u8fdb\u5236\u6709\u6548\u4f4d 53 \u00d70.3010\u224815.95<\/p>\n
\u00a0👉double \u7ea6 15\u201116 \u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57\u3002<\/p>\n
\n\u901a\u4fd7\u89e3\u91ca<\/p>\n
\u4e8c\u8fdb\u5236\u6bcf\u589e\u52a0 1bit，\u80fd\u533a\u5206 2 \u500d\u5927\u5c0f； \u5341\u8fdb\u5236\u6bcf\u589e\u52a0 1 \u4f4d，\u80fd\u533a\u5206 10 \u500d\u5927\u5c0f\u3002<\/p>\n
log\u2081\u20802 \u2248 0.3010\u542b\u4e49：1 \u4e2a\u4e8c\u8fdb\u5236 bit \u2248 0.301 \u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57\u3002<\/p>\n
- \n
- float：24bit \u00d70.301 \u22487.2 \u4f4d；<\/li>\n
- double：53bit \u00d70.301\u224816 \u4f4d\u3002<\/li>\n<\/ul>\n
\u26a0\ufe0f\u533a\u5206\u4e24\u4ef6\u4e8b：<\/p>\n
- \u6709\u6548\u6570\u5b57：\u53ef\u9760\u7684\u6570\u5b57\u4f4d\u6570，\u4e0d\u662f\u5c0f\u6570\u70b9\u540e\u9762\u591a\u5c11\u4f4d\u3002 \u4f8b：16777217.0f，\u6574\u6570 8 \u4f4d，float \u53ea\u6709 7 \u4f4d\u6709\u6548\u7cbe\u5ea6，\u6700\u4f4e\u4f4d\u76f4\u63a5\u4e22\u5931\u3002<\/li>\n
- printf("%.20f")\u6253\u5370\u5f88\u591a\u5c0f\u6570，\u540e\u9762\u4e00\u5927\u4e32\u662f\u865a\u5047\u7684，\u53ea\u6709\u524d 6\u20117 \u4f4d\u53ef\u4fe1\u3002<\/li>\n
\u4e3e\u5b9e\u4f8b<\/p>\n
c<\/p>\n
float x = 12345678.0f;
\nprintf("%f",x);<\/p>\n\u771f\u5b9e\u6570\u5b57：12345678 float \u8f93\u51fa：12345678？\u5b9e\u9645\u4f1a\u53d1\u751f\u504f\u5dee\u3002<\/p>\n
\u4e00\u5171 8 \u4f4d\u6709\u6548\u5341\u8fdb\u5236\u6570\u5b57，\u8d85\u51fa float\u22487.2 \u4f4d\u6781\u9650，\u6700\u4f4e\u4f4d\u4e0d\u51c6\u3002<\/p>\n
\n\u9636\u7801\u504f\u79fb（\u79fb\u7801）<\/h2>\n
IEEE\u2011754 \u7684\u9636\u7801\u4e0d\u76f4\u63a5\u5b58\u771f\u5b9e\u6307\u6570，\u8981\u52a0\u4e0a\u4e00\u4e2a\u504f\u79fb\u91cf\u3002<\/p>\n
- \n
- float（32 \u4f4d）：\u504f\u79fb\u91cf = 127<\/li>\n
- double（64 \u4f4d）：\u504f\u79fb\u91cf = 1023<\/li>\n<\/ul>\n
\u516c\u5f0f：<\/p>\n
\u5b58\u50a8\u7684\u9636\u7801 = \u771f\u5b9e\u6307\u6570 + \u504f\u79fb\u91cf \u771f\u5b9e\u6307\u6570 = \u5b58\u50a8\u9636\u7801 \u2212 \u504f\u79fb\u91cf<\/p>\n
\u4e3e\u4f8b：<\/p>\n
\u4e8c\u8fdb\u5236\u79d1\u5b66\u8ba1\u6570
![\"1.011](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094942-6a9d373630f5c.png\")
<\/p>\n\u771f\u5b9e\u6307\u6570 =3；float \u5b58\u5165\u9636\u7801\u5b57\u6bb5\u7684\u503c = 3+127=130\u3002<\/p>\n
\u7279\u6b8a\u89c4\u5219：\u9636\u7801\u4e24\u79cd\u8fb9\u754c\u60c5\u51b5<\/h3>\n
- \u9636\u7801\u5168\u90e8\u6bd4\u7279\u4e3a 1\n
- \n
- \u5c3e\u6570\u5168 0：\u65e0\u7a77\u5927（inf）<\/li>\n
- \u5c3e\u6570\u975e 0：\u975e\u6570\u5b57（NaN，\u65e0\u6548\u8ba1\u7b97\u7ed3\u679c，\u6bd4\u5982 0 \u9664\u4ee5 0）<\/li>\n<\/ul>\n<\/li>\n
- \u9636\u7801\u5168\u90e8\u6bd4\u7279\u4e3a 0\n
- \n
- \u4ee3\u8868\u975e\u89c4\u683c\u5316\u6570，\u7528\u6765\u8868\u793a\u63a5\u8fd1 0 \u7684\u6781\u5c0f\u6570\u5b57；\u6b64\u65f6\u4e0d\u518d\u9690\u85cf\u5f00\u5934\u76841\u3002<\/li>\n<\/ul>\n<\/li>\n
\u6b63\u5e38\u4f7f\u7528\u7684\u666e\u901a\u6d6e\u70b9\u6570，\u9636\u7801\u65e2\u4e0d\u5168 0，\u4e5f\u4e0d\u5168 1\u3002<\/p>\n
c<\/p>\n
#include <cstdio>
\nint main()
\n{
\n float a = 1.0f \/ 0.0f;
\n printf("%f\\\\n", a); \/\/\u8f93\u51fa inf \u65e0\u7a77\u5927
\n return 0;
\n}<\/p>\n![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094942-6a9d373637555.png\")
<\/p>\n
\n\u601d\u8003\u9898<\/p>\n
- float \u7684\u9636\u7801\u504f\u79fb\u91cf\u662f\u591a\u5c11？double \u7684\u504f\u79fb\u91cf？<\/li>\n
- \u82e5 float \u771f\u5b9e\u6307\u6570\u662f 5，\u90a3\u4e48\u5b58\u5165\u9636\u7801\u5b57\u6bb5\u7684\u6570\u503c\u662f\u591a\u5c11？<\/li>\n
- float \u9636\u7801\u6240\u6709 bit \u5168\u4e3a 1，\u5c3e\u6570\u4e0d\u4e3a 0，\u8868\u793a\u4ec0\u4e48？<\/li>\n
：<\/span><\/p>\n
1.127 1023<\/span><\/p>\n
2.132 <\/span><\/p>\n
3.\u65e0\u6570\u5b57<\/span><\/p>\n
：<\/span><\/p>\n
\u6279\u6539<\/p>\n
- float \u504f\u79fb：127；double \u504f\u79fb：1023\u2003\u2705\u6b63\u786e<\/li>\n
- 5 + 127 = 130\u2003\u2705\u6b63\u786e<\/li>\n
- \u8868\u8ff0\u5c0f\u95ee\u9898：\u6807\u51c6\u540d\u79f0\u662f NaN（Not a Number，\u975e\u6570\u5b57），\u4e0d\u662f \u201c\u65e0\u6570\u5b57\u201d\u3002\u4ee3\u8868\u65e0\u6548\u8fd0\u7b97\u7ed3\u679c，\u4f8b\u5982 0.0\/0.0\u3002<\/li>\n
\u5c0f\u8bb0\u5fc6：<\/p>\n
- \n
- \u9636\u7801\u5168 1，\u5c3e\u6570 = 0 \u2192\u65e0\u7a77\u5927 inf<\/li>\n
- \u9636\u7801\u5168 1，\u5c3e\u6570\u22600 \u2192 NaN<\/li>\n<\/ul>\n
\n\u5c3e\u6570 M，\u9690\u85cf\u7684\u6574\u6570\u4f4d 1<\/h2>\n
IEEE\u2011754 \u89c4\u683c\u5316\u6d6e\u70b9\u6570（\u65e5\u5e38\u7edd\u5927\u591a\u6570\u6d6e\u70b9\u6570） \u4e8c\u8fdb\u5236\u79d1\u5b66\u8ba1\u6570\u6cd5\u7edf\u4e00\u5199\u6210<\/p>\n
![\"1.M*2^{E}\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094943-6a9d3737395d5.png\")
\u00a0（E\u4e3a\u771f\u5b9e\u7684E，\u9664\u53bb\u504f\u79fb\u91cf）<\/p>\n\u91cd\u70b9：\u5f00\u5934\u8fd9\u4e2a\u6574\u6570 1，\u4e0d\u5b58\u5165\u5185\u5b58，\u662f\u9690\u85cf\u4f4d\u3002 \u5185\u5b58\u91cc\u9762 23bit \u5c3e\u6570 M，\u53ea\u5b58\u5c0f\u6570\u70b9\u540e\u9762\u7684\u90e8\u5206\u3002<\/p>\n
\u793a\u4f8b：<\/p>\n
\u4e8c\u8fdb\u5236<\/p>\n
\u00a0
![\"1.1010*2^E\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094943-6a9d37374001b.png\")
<\/p>\n- \n
- \u6574\u6570\u4f4d1\u4e22\u6389\u4e0d\u5b58<\/li>\n
- \u5c3e\u6570 M \u5185\u5b58\u53ea\u4fdd\u5b58：1010，\u540e\u9762\u8865 0 \u586b\u6ee1 23bit\u3002 \u8bfb\u53d6\u6570\u636e\u7684\u65f6\u5019\u786c\u4ef6\u81ea\u52a8\u628a1\u8865\u56de\u6765\u3002<\/li>\n<\/ul>\n
\u6536\u76ca：\u767d\u767d\u591a\u51fa 1 \u4f4d\u6709\u6548\u7cbe\u5ea6，\u8fd9\u5c31\u662f float23bit \u5c3e\u6570\u5374\u62e5\u6709\u63a5\u8fd1 7 \u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57\u7684\u539f\u56e0\u3002<\/p>\n
\u975e\u89c4\u683c\u5316\u6570（\u9636\u7801\u5168\u90e8 bit \u4e3a 0）<\/h3>\n
\u5f53\u9636\u7801\u5168 0，\u4e0d\u518d\u4f7f\u7528\u9690\u85cf\u76841，\u6570\u5b57\u683c\u5f0f\u53d8\u4e3a：<\/p>\n
<\/p>\n\u7528\u9014：\u8868\u793a\u65e0\u9650\u8d8b\u8fd1 0 \u7684\u6781\u5c0f\u6570\u5b57，\u586b\u8865 0 \u9644\u8fd1\u7684\u6570\u503c\u7a7a\u9699\u3002<\/p>\n
\u533a\u5206：<\/p>\n
- \n
- \u2705\u6b63\u5e38\u6570\u5b57：\u9636\u7801\u4e0d\u5168 0 \u4e0d\u5168 1 \u2192\u89c4\u683c\u5316\u6570，\u9690\u85cf1.M<\/li>\n
- \u2705\u9636\u7801\u5168 0：\u975e\u89c4\u683c\u5316\u6570，\u6ca1\u6709\u9690\u85cf\u7684 1<\/li>\n
- \u2705\u9636\u7801\u5168 1：\u7279\u6b8a\u503c inf \/ NaN<\/li>\n<\/ul>\n
c<\/p>\n
#include <cstdio>
\nint main(void)
\n{
\n float x = 1.0f \/ 3.0f;
\n printf("%f\\\\n",x);
\n return 0;
\n}<\/p>\n![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094943-6a9d373746604.png\")
<\/p>\n
\n\u601d\u8003\u9898<\/p>\n
- \u89c4\u683c\u5316 float，\u5c3e\u6570\u90e8\u5206\u5185\u5b58\u4fdd\u5b58\u7684\u662f 1.M \u8fd8\u662f\u5c0f\u6570\u70b9\u540e\u7684M？<\/li>\n
- float \u4e3a\u4ec0\u4e48 23 \u4f4d\u5c3e\u6570，\u5374\u80fd\u5b9e\u73b0\u7ea6 7 \u4f4d\u6709\u6548\u5341\u8fdb\u5236\u6570\u5b57？<\/li>\n
- \u4ec0\u4e48\u65f6\u5019\u6d6e\u70b9\u6570\u4e0d\u518d\u9690\u85cf\u6574\u6570\u4f4d 1？<\/li>\n
：<\/span><\/p>\n
1.（M）<\/span><\/p>\n
2.\u7701\u7565\u4e86\u6574\u6570\u4f4d<\/span><\/p>\n
3.\u975e\u89c4\u683c\u5316\u6570<\/span><\/p>\n
：<\/span><\/p>\n
\u6279\u6539<\/p>\n
- \u2705\u6b63\u786e：\u5185\u5b58\u5c3e\u6570\u53ea\u4fdd\u5b58\u5c0f\u6570\u70b9\u540e\u9762\u7684 M，\u4e0d\u4f1a\u5b58\u524d\u9762\u7684 1\u3002 \u903b\u8f91：\u5b9e\u9645\u5185\u5b58\u5b58 M；\u8bfb\u53d6\u7684\u65f6\u5019\u786c\u4ef6\u81ea\u52a8\u62fc\u63a5\u62101.M\u3002<\/li>\n
\u9898\u76ee\u9677\u9631：\u5185\u5b58\u91cc\u5b58\u7684\u4e0d\u662f1.M，\u53ea\u5b58\u5c0f\u6570\u90e8\u5206M\u3002<\/p>\n
- \n
\u2705\u6b63\u786e：\u7701\u7565\u9690\u85cf\u6574\u6570\u4f4d 1，\u51ed\u7a7a\u591a\u51fa 1bit \u6709\u6548\u7cbe\u5ea6\u3002<\/p>\n<\/li>\n
- \n
\u2705\u6b63\u786e：\u9636\u7801\u5168 0，\u8fdb\u5165\u975e\u89c4\u683c\u5316\u6570，\u4e0d\u518d\u9690\u85cf\u6574\u6570\u4f4d 1\u3002<\/p>\n<\/li>\n
\u518d\u590d\u8ff0\u4e00\u904d\u52a0\u6df1\u5370\u8c61： \u8ba1\u7b97：<\/p>\n
![\"1.101](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094944-6a9d373834f98.png\")
\u5185\u5b58\u5c3e\u6570 23bit，<\/p>\n\u53ea\u5b58：101，\u524d\u9762\u76841\u4e0d\u5199\u5165\u5185\u5b58\u3002<\/p>\n
\n\u5b9e\u9645\u5f00\u53d1 \/ \u505a\u9898\u5751\u70b9<\/h2>\n
\u4e8c\u8fdb\u5236\u6d6e\u70b9\u6570\u4e0d\u80fd\u7cbe\u786e\u8868\u8fbe\u90e8\u5206\u5341\u8fdb\u5236\u5c0f\u6570<\/h3>\n
\u5341\u8fdb\u52360.1，\u8f6c\u4e8c\u8fdb\u5236\u662f\u65e0\u9650\u5faa\u73af\u5c0f\u6570\u3002 \u4f46\u662f float \u5185\u5b58\u53ea\u6709\u6709\u9650\u6bd4\u7279，\u53ea\u80fd\u622a\u65ad\u4fdd\u5b58\u8fd1\u4f3c\u503c\u3002 \u6240\u4ee5\u5185\u5b58\u4e2d0.1\u5e76\u4e0d\u662f\u771f\u6b63\u7b49\u4e8e 0.1\u3002<\/p>\n
cpp<\/p>\n
#include <cstdio>
\n#include <cmath>
\nint main()
\n{
\n float a = 0.1f;
\n if(a == 0.1)
\n {
\n printf("\u76f8\u7b49");
\n }
\n else
\n {
\n printf("\u4e0d\u76f8\u7b49");
\n }
\n return 0;
\n}<\/p>\n\u8f93\u51fa\u7ed3\u679c：\u4e0d\u76f8\u7b49<\/p>\n
0.1\u5b57\u9762\u91cf\u9ed8\u8ba4\u662f double \u7c7b\u578b；a\u662f float，\u4e24\u8005\u8fd1\u4f3c\u503c\u4e0d\u4e00\u6837\u3002<\/p>\n
\u4e0d\u8981\u7528 == \u5224\u65ad\u4e24\u4e2a\u6d6e\u70b9\u6570\u76f8\u7b49<\/h3>\n
\u6d6e\u70b9\u6570\u6709\u5fae\u5c0f\u8bef\u5dee，\u4e0d\u80fd\u76f4\u63a5 if(x == y)\u3002<\/p>\n
\u2705\u6b63\u786e\u5199\u6cd5：\u5224\u65ad\u4e24\u8005\u5dee\u503c\u7684\u7edd\u5bf9\u503c\u5c0f\u4e8e\u4e00\u4e2a\u6781\u5c0f\u5141\u8bb8\u8bef\u5dee<\/p>\n
cpp<\/p>\n
#include <cmath>
\n\/\/ \u5141\u8bb8\u8bef\u5dee 1e\u20116
\nif(fabs(a – b) < 1e\u20116)
\n{
\n \/\/\u89c6\u4e3a\u4e24\u4e2a\u6d6e\u70b9\u6570\u8fd1\u4f3c\u76f8\u7b49
\n}<\/p>\nfabs()：\u6c42\u6d6e\u70b9\u6570\u7edd\u5bf9\u503c；abs()\u7528\u4e8e\u6574\u6570\u3002<\/p>\n
\u533a\u5206\u4e24\u4e2a\u6982\u5ff5<\/p>\n
- \u8868\u793a\u8303\u56f4：float \u53ef\u4ee5\u5b58\u5f88\u5927\u7684\u6570\u5b57；<\/li>\n
- \u6709\u6548\u7cbe\u5ea6：\u6570\u5b57\u4f4d\u6570\u4e00\u591a，\u5c3e\u90e8\u5c0f\u6570\u4e0d\u51c6\u3002<\/li>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094944-6a9d37383b621.png\")
<\/p>\n
\n\u601d\u8003\u9898<\/p>\n
- \u4e3a\u4ec0\u4e48 0.1 \u4e0d\u80fd\u5728 float \u4e2d\u7cbe\u786e\u5b58\u50a8？<\/li>\n
- \u6d6e\u70b9\u6570\u6bd4\u8f83\u76f8\u7b49，\u4e3a\u4ec0\u4e48\u4e0d\u80fd\u76f4\u63a5\u7528 ==？\u5e94\u8be5\u600e\u4e48\u5199？<\/li>\n
- float\u3001double \u6709\u6548\u6570\u5b57\u5206\u522b\u5927\u7ea6\u591a\u5c11\u4f4d？<\/li>\n
：<\/span><\/p>\n
1.\u4e0d\u80fd <\/span><\/p>\n
2.\u505a\u5dee,\u5176\u5dee\u5c0f\u4e8e\u4e00\u5b9a\u8303\u56f4<\/span><\/p>\n
3.6-7\u4f4d 15-16\u4f4d<\/span><\/p>\n
0.1\u5177\u4f53\u5728\u4e8c\u8fdb\u5236\u662f\u600e\u4e48\u5b58\u50a8\u7684\u5462？<\/span><\/p>\n
：<\/span><\/p>\n
\u6279\u6539<\/p>\n
- \u2705\u6b63\u786e\u3002\u5341\u8fdb\u52360.1\u8f6c\u4e8c\u8fdb\u5236\u662f\u65e0\u9650\u5faa\u73af\u5c0f\u6570，float \u5b58\u50a8\u7a7a\u95f4\u6709\u9650，\u53ea\u80fd\u4fdd\u5b58\u8fd1\u4f3c\u503c，\u65e0\u6cd5\u7cbe\u786e\u5b58\u653e\u3002<\/li>\n
- \u2705\u5927\u4f53\u6b63\u786e；\u5b8c\u6574\u8868\u8ff0：\u8ba1\u7b97\u4e24\u8005\u5dee\u503c\u7edd\u5bf9\u503c，fabs(a\u2011b) < \u6781\u5c0f\u503c(\u4f8b\u59821e\u20116)，\u5c31\u8ba4\u4e3a\u8fd1\u4f3c\u76f8\u7b49\u3002<\/li>\n
\u6ce8\u610f：\u6d6e\u70b9\u6570\u6c42\u7edd\u5bf9\u503c\u51fd\u6570\u662ffabs()；\u6574\u6570\u7528abs()，\u4e0d\u8981\u5199\u6df7\u3002<\/p>\n
- \u2705\u6b63\u786e：float：6\u20117 \u4f4d\u6709\u6548\u6570\u5b57；double：15\u201116 \u4f4d\u6709\u6548\u6570\u5b57\u3002<\/li>\n
\n\u5341\u8fdb\u5236 0.1 \u2192 float \u5b8c\u6574\u6f14\u7b97<\/h3>\n
\u5341\u8fdb\u5236 \\\\(0.1_{10}\\\\)<\/p>\n
\u7b2c\u4e00\u6b65：\u8f6c\u4e8c\u8fdb\u5236<\/p>\n
\u7528\u4e58 2 \u53d6\u6574\u6cd5：<\/p>\n
plaintext<\/p>\n
0.1 \u00d72 =0.2 \u53d60
\n0.2 \u00d72 =0.4 \u53d60
\n0.4 \u00d72 =0.8 \u53d60
\n0.8 \u00d72 =1.6 \u53d61
\n0.6 \u00d72 =1.2 \u53d61
\n0.2 \u00d72 =0.4 \u53d60
\n0.4 \u00d72 =0.8 \u53d60
\n0.8 \u00d72 =1.6 \u53d61
\n\u2026\u2026\u5faa\u73af\u5f80\u590d<\/p>\n\u5f97\u5230\u4e8c\u8fdb\u5236：0.0001100110011……<\/p>\n
0011\u65e0\u9650\u5faa\u73af，\u6c38\u8fdc\u5199\u4e0d\u5b8c\u3002<\/p>\n
\u7b2c\u4e8c\u6b65：\u5199\u6210\u89c4\u683c\u5316\u79d1\u5b66\u8ba1\u6570\u6cd5（IEEE\u2011754）<\/p>\n
\u628a\u5c0f\u6570\u70b9\u53f3\u79fb 4 \u4f4d：<\/p>\n
![\"1.100110011......*](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094945-6a9d373939f72.png\")
<\/p>\n- \n
- \u7b26\u53f7\u4f4d：\u6b63\u6570 \u2192 0<\/li>\n
- \u771f\u5b9e\u6307\u6570 E \u771f\u5b9e = -4<\/li>\n
- float \u5b58\u50a8\u9636\u7801 = \u771f\u5b9e\u6307\u6570 +127 = -4+127 = 123<\/li>\n<\/ul>\n
\u7b2c\u4e09\u6b65：\u5c3e\u6570 M（\u5185\u5b58\u53ea\u5b58\u5c0f\u6570\u70b9\u540e\u9762\u90e8\u5206）<\/p>\n
\u903b\u8f91\u6570\u503c：1.100110011 0011 0011\u2026\u2026<\/p>\n
\u524d\u97621.\u9690\u85cf，\u5185\u5b58\u5c3e\u6570 23bit \u53ea\u4fdd\u5b58\u5c0f\u6570\u70b9\u4e4b\u540e：10011001100110011001101<\/p>\n
\u56e0\u4e3a\u53ea\u80fd\u5b58 23 \u4f4d，\u65e0\u9650\u5faa\u73af\u7684\u6bd4\u7279\u76f4\u63a5\u622a\u65ad，\u672b\u5c3e\u505a\u820d\u5165\u3002 👉\u6240\u4ee5\u5185\u5b58\u91cc\u9762\u5b58\u7684，\u5e76\u4e0d\u662f\u771f\u6b63\u7684 0.1，\u662f\u4e00\u4e2a\u975e\u5e38\u63a5\u8fd1 0.1 \u7684\u8fd1\u4f3c\u503c\u3002<\/p>\n
\u5b8c\u6574 float \u5185\u5b58 32bit \u6392\u5e03<\/p>\n
\u8868\u683c<\/p>\n
\n
\u7b26\u53f7 (1bit)\u9636\u7801 (8bit)\u5c3e\u6570 M (23bit)<\/tr>\n \n\n 0<\/td>\n 01111011（123）<\/td>\n 10011001100110011001101<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n \u5bf9\u5e94\u4ee3\u7801\u73b0\u8c61<\/p>\n
c<\/p>\n
float f = 0.1f;
\nprintf("%.20f",f);<\/p>\n\u8f93\u51fa： 0.10000000149011611938<\/p>\n
\u53ef\u4ee5\u770b\u89c1，\u5e76\u4e0d\u662f\u4e25\u683c\u7b49\u4e8e 0.1\u3002<\/p>\n
\nIEEE\u2011754 \u7279\u6b8a\u503c<\/h2>\n
\u9664\u666e\u901a\u89c4\u683c\u5316\u6d6e\u70b9\u6570，IEEE\u2011754 \u5b9a\u4e49\u4e86\u51e0\u7ec4\u7279\u6b8a\u6570\u503c，\u7531\u9636\u7801\u7684\u8fb9\u754c\u72b6\u6001\u51b3\u5b9a\u3002<\/p>\n
1. \u00b10 \u96f6<\/h3>\n
\u9636\u7801\u5168\u90e8 bit \u4e3a 0，\u5c3e\u6570 M \u5168\u90e8 bit \u4e3a 0\u3002 \u7b26\u53f7\u4f4d\u53ef\u4ee5 0 \u6216\u8005 1，\u4e8e\u662f\u5b58\u5728+0.0\u548c\u20110.0\u3002 \u7edd\u5927\u591a\u6570\u573a\u666f\u4e0b\u4e24\u8005\u8fd0\u7b97\u6548\u679c\u51e0\u4e4e\u4e00\u6837\u3002<\/p>\n
2. Inf \u65e0\u7a77\u5927<\/h3>\n
\u9636\u7801\u5168\u90e8 bit \u4e3a 1，\u5c3e\u6570 M=0\u3002<\/p>\n
- \n
- \u7b26\u53f7\u4f4d 0：\u6b63\u65e0\u7a77 +inf<\/li>\n
- \u7b26\u53f7\u4f4d 1：\u8d1f\u65e0\u7a77 -inf \u4ea7\u751f\u573a\u666f：\u6b63\u6570\u9664\u4ee5 0，\u5f97\u5230\u6b63\u65e0\u7a77\u3002<\/li>\n<\/ul>\n
3. NaN（Not a Number，\u975e\u6570）<\/h3>\n
\u9636\u7801\u5168\u90e8 bit \u4e3a 1，\u5c3e\u6570 M \u4e0d\u4e3a 0\u3002<\/p>\n
\u4ee3\u8868\u65e0\u6548\u6570\u5b66\u8fd0\u7b97：0.0 \/ 0.0\u3001sqrt(-1.0)\u8d1f\u6570\u5f00\u6839\u53f7\u3002<\/p>\n
\u2b50NaN \u6700\u72ec\u7279\u6027\u8d28：NaN \u4e0d\u7b49\u4e8e\u4efb\u4f55\u6570\u5b57，\u751a\u81f3 NaN == NaN \u7684\u7ed3\u679c\u4e5f\u662f\u5047\u3002 \u4e0d\u80fd\u7528 x == NaN \u5224\u65ad\u662f\u5426\u662f\u975e\u6570；C \u8bed\u8a00\u7528isnan(x)\u51fd\u6570\u5224\u65ad\u3002<\/p>\n
c<\/p>\n
#include <cstdio>
\n#include <cmath>
\nint main(void)
\n{
\n float a = 0.0f \/ 0.0f;
\n printf("%f\\\\n", a);
\n if(a == a)
\n {
\n printf("a\u7b49\u4e8e\u81ea\u5df1");
\n }
\n else
\n {
\n printf("a\u4e0d\u7b49\u4e8e\u81ea\u5df1");
\n }
\n return 0;
\n}<\/p>\n\u8fd0\u884c\u8f93\u51fa：<\/p>\n
plaintext<\/p>\n
nan
\na\u4e0d\u7b49\u4e8e\u81ea\u5df1<\/p>\n
\n\u601d\u8003\u9898<\/p>\n
- float \u9636\u7801\u5168 1，\u5c3e\u6570 M \u7b49\u4e8e 0，\u4ee3\u8868\u4ec0\u4e48？<\/li>\n
- NaN \u6709\u4e00\u4e2a\u5f88\u7279\u6b8a\u7684\u5224\u65ad\u7279\u6027\u662f\u4ec0\u4e48？<\/li>\n
- \u4ec0\u4e48\u8fd0\u7b97\u4f1a\u4ea7\u751f NaN？\u4e3e\u4e00\u4e2a\u4f8b\u5b50\u3002<\/li>\n
：<\/span><\/p>\n
1.\u65e0\u7a77\u5927 <\/span><\/p>\n
2.NaN != NaN<\/span><\/p>\n
3.0\/0<\/span><\/p>\n
：<\/span><\/p>\n
\u6279\u6539<\/p>\n
- \u2705\u65e0\u7a77\u5927（Inf），\u7b26\u53f7\u4f4d\u51b3\u5b9a\u662f\u6b63\u65e0\u7a77\u8fd8\u662f\u8d1f\u65e0\u7a77\u3002<\/li>\n
- \u2705NaN != NaN，NaN \u8fde\u81ea\u5df1\u90fd\u4e0d\u7b49\u4e8e\u81ea\u5df1，\u4e0d\u80fd\u7528==\u5224\u65ad NaN\u3002<\/li>\n
- \u27050.0 \/ 0.0\u4f1a\u4ea7\u751f NaN；\u8865\u5145：\u8d1f\u6570\u5f00\u5e73\u65b9sqrt(-1)\u4e5f\u4f1a\u5f97\u5230 NaN\u3002<\/li>\n
\u5c0f\u63d0\u9192：\u5fc5\u987b\u662f\u6d6e\u70b9\u6570 0 \u76f8\u9664；\u6574\u65700\/0\u7a0b\u5e8f\u76f4\u63a5\u5d29\u6e83，\u4e0d\u662f NaN\u3002<\/p>\n
![\"\"](\"https:\/\/www.wsisp.com\/helps\/wp-content\/uploads\/2026\/09\/20260906094945-6a9d373941766.png\")
<\/p>\n
\n\u5c0f\u7ed3\u7279\u6b8a\u503c<\/h3>\n
\u8868\u683c<\/p>\n
\n
\u6761\u4ef6\u7ed3\u679c<\/tr>\n \n\n \u9636\u7801\u5168 0，\u5c3e\u6570\u5168 0<\/td>\n \u00b10<\/td>\n<\/tr>\n \n \u9636\u7801\u5168 1，\u5c3e\u6570\u5168 0<\/td>\n \u00b1Inf \u65e0\u7a77\u5927<\/td>\n<\/tr>\n \n \u9636\u7801\u5168 1，\u5c3e\u6570\u975e 0<\/td>\n NaN \u975e\u6570<\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n \u51e0\u4e2a\u7ecf\u5178\u7684\u6d6e\u70b9\u6570\u5b58\u50a8\u7a0b\u5e8f\u53ef\u89c6\u5316<\/h2>\n
#include <cstdio>
\n#include <cstdint><\/p>\n\/\/\u6253\u5370float\u5185\u5b58\u539f\u59cb\u6bd4\u7279：\u7b26\u53f7｜8\u9636\u7801｜23\u5c3e\u6570
\nvoid printFloatBits(float num)
\n{
\n uint32_t bits = *(uint32_t*)#<\/p>\nprintf("float = %.20f\\\\n", num);
\n printf("32bit\u5185\u5b58：");
\n for (int i = 31; i >= 0; i–)
\n {
\n uint32_t mask = 1U << i;
\n printf("%c", (bits & mask) ? '1' : '0');
\n if (i == 31) printf(" "); \/\/\u7b26\u53f7\u4f4d\u5206\u9694
\n if (i == 23) printf(" "); \/\/\u9636\u7801\u3001\u5c3e\u6570\u4f4d\u5206\u9694
\n }
\n printf("\\\\n—————————————-\\\\n");
\n}<\/p>\nint main(void)
\n{
\n \/\/ \u5178\u578b\u6848\u4f8b
\n printFloatBits(0.1f); \/\/\u6848\u4f8b1：\u7ecf\u5178\u65e0\u6cd5\u7cbe\u786e\u5b58\u50a8，\u4e8c\u8fdb\u5236\u65e0\u9650\u5faa\u73af
\n printFloatBits(5.0f); \/\/\u6848\u4f8b2：\u53ef\u4ee5\u7cbe\u786e\u5b58\u50a8\u7684\u6b63\u6570 101.0 \u2192 1.01 \u00d72^2
\n printFloatBits(1.0f \/ 3.0f); \/\/\u6848\u4f8b3：1\/3\u65e0\u9650\u5faa\u73af\u5c0f\u6570
\n printFloatBits(-2.0f); \/\/\u6848\u4f8b4：\u8d1f\u6570，\u89c2\u5bdf\u7b26\u53f7\u4f4d\u53d8\u4e3a1
\n printFloatBits(0.0f); \/\/\u6848\u4f8b5：\u6b630，\u9636\u7801\u51680，\u5c3e\u6570\u51680
\n \/\/printFloatBits(1.0f \/ 0.0f); \/\/\u6848\u4f8b6：\u6b63\u65e0\u7a77Inf，\u9636\u7801\u5168\u90e8\u7f6e1 \u4e86\u89e3，\u771f\u6b63\u4ee3\u7801\u4e0d\u53ef\u6267\u884c
\n return 0;
\n} <\/p>\n
\n\u603b\u7ed3<\/h2>\n
\u6838\u5fc3\u56de\u987e<\/p>\n
- 32 \u4f4d float<\/li>\n
- \n
- \u7b26\u53f7\u4f4d：1bit；\u9636\u7801：8bit；\u5c3e\u6570：23bit；\u504f\u79fb\u91cf：127<\/li>\n
- \u89c4\u683c\u5316\u6570：\u903b\u8f91 \\\\(1.M\u00d72^{E\u771f\u5b9e}\\\\)；\u5185\u5b58\u53ea\u5b58 M，\u9690\u85cf\u6574\u65701<\/li>\n
- \u6709\u6548\u6570\u5b57：6\u20117 \u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57<\/li>\n<\/ul>\n
- 64 \u4f4d double<\/li>\n
- \n
- \u7b26\u53f7\u4f4d：1bit；\u9636\u7801：11bit；\u5c3e\u6570：52bit；\u504f\u79fb\u91cf：1023<\/li>\n
- \u6709\u6548\u6570\u5b57：15\u201116 \u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57<\/li>\n<\/ul>\n
- \u8fb9\u754c\u7279\u6b8a\u60c5\u51b5<\/li>\n
- \n
- \u9636\u7801\u5168 0：\u975e\u89c4\u683c\u5316\u6570，\u65e0\u9690\u85cf 1，\u8868\u793a\u6781\u5c0f\u6570\u5b57，\u53ef\u5f97\u5230 \u00b10<\/li>\n
- \u9636\u7801\u5168 1，\u5c3e\u6570 0：\u65e0\u7a77\u5927 Inf<\/li>\n
- \u9636\u7801\u5168 1，\u5c3e\u6570\u22600：NaN，\u975e\u6570，NaN \u4e0d\u7b49\u4e8e\u81ea\u8eab<\/li>\n<\/ul>\n
- \u5de5\u7a0b\u505a\u9898\u94c1\u5f8b<\/li>\n
- \n
- \u5f88\u591a\u5341\u8fdb\u5236\u5c0f\u6570（0.1）\u4e8c\u8fdb\u5236\u65e0\u6cd5\u7cbe\u786e\u5b58\u50a8，\u53ea\u80fd\u8fd1\u4f3c；<\/li>\n
- \u274c\u4e25\u7981\u76f4\u63a5\u4f7f\u7528==\u6bd4\u8f83\u6d6e\u70b9\u6570；\u2705\u91c7\u7528fabs(a\u2011b) < 1e\u20116\u8fd1\u4f3c\u5224\u65ad；<\/li>\n
- OJ \u505a\u9898\u6d6e\u70b9\u8ba1\u7b97\u4f18\u5148\u9009\u62e9double，\u51cf\u5c11\u7cbe\u5ea6\u4e22\u5931\u3002<\/li>\n<\/ul>\n
c<\/p>\n
\/\/\u6d6e\u70b9\u6570\u8fd1\u4f3c\u76f8\u7b49\u6a21\u677f
\n#include <cmath>
\nif(fabs(a – b) < 1e-6)
\n{
\n \/\/\u89c6\u4e3a\u76f8\u7b49
\n}<\/p>\n","protected":false},"excerpt":{"rendered":"\u76ee\u5f55
\nIEEE\u2011754 \u57fa\u7840\u6982\u5ff5
\n\u4e3a\u4f55\u89c4\u683c\u5316\u6d6e\u70b9\u6570\u6574\u6570\u4f4d\u53ea\u80fd\u662f 1
\n\u4e8c\u8fdb\u5236\u6570\u5b57\u7279\u70b9
\nfloat 23bit \u5c3e\u6570，\u4e3a\u4ec0\u4e48\u5f97\u5230\u5927\u7ea6 7 \u4f4d\u5341\u8fdb\u5236\u6709\u6548\u6570\u5b57
\n\u9636\u7801\u504f\u79fb（\u79fb\u7801）
\n\u7279\u6b8a\u89c4\u5219：\u9636\u7801\u4e24\u79cd\u8fb9\u754c\u60c5\u51b5
\n\u5c3e\u6570 M，\u9690\u85cf\u7684\u6574\u6570\u4f4d 1
\n\u975e\u89c4\u683c\u5316\u6570（\u9636\u7801\u5168\u90e8 bit \u4e3a 0）
\n\u5b9e\u9645\u5f00\u53d1 \/ \u505a\u9898\u5751\u70b9
\n\u4e8c\u8fdb\u5236\u6d6e\u70b9\u6570\u4e0d\u80fd\u7cbe\u786e\u8868\u8fbe\u90e8\u5206\u5341\u8fdb\u5236\u5c0f\u6570
\n\u4e0d\u8981\u7528 \u5224\u65ad\u4e24\u4e2a\u6d6e\u70b9\u6570\u76f8\u7b49 <\/p>\n","protected":false},"author":2,"featured_media":101359,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[11587,11588,55,371],"topic":[],"class_list":["post-101374","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-server","tag-ieee-754","tag-11588","tag-c","tag-371"],"yoast_head":"\n\u6d6e\u70b9\u6570\u7684\u5b58\u50a8\uff1aIEEE\u2011754 - \u7f51\u7855\u4e92\u8054\u5e2e\u52a9\u4e2d\u5fc3<\/title>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.wsisp.com\/helps\/101374.html\" \/>\n<meta property=\"og:locale\" content=\"zh_CN\" \/>\n<meta property=\"og:type\" content=\"article\" \/>\n<meta property=\"og:title\" content=\"\u6d6e\u70b9\u6570\u7684\u5b58\u50a8\uff1aIEEE\u2011754 - 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