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href\u003D\"https://simulink.wiki/t/2d65182b62497c437a74485c0706\" rel\u003D\"nofollow\"\u003EEmbeded Coder\u003C/a\u003E生成代码，会自动处理浮点数除零的情况。\u003C/p\u003E\u003Ch3\u003E整数除零\u003C/h3\u003E\u003Cp\u003E在C语言中，整数除以零是未定义行为（Undefined Behavior）。\u003C/p\u003E\u003Cp\u003E这意味着编译器和运行时环境可以以任何方式处理这种情况，包括但不限于以下几种：\u003C/p\u003E\u003Col\u003E\u003Cli data-list\u003D\"bullet\"\u003E\u003Cspan class\u003D\"ql-ui\" contenteditable\u003D\"false\"\u003E\u003C/span\u003E程序崩溃或硬件异常：特别是在嵌入式系统，最常见的情况是程序会立即崩溃，并产生一个运行时错误，例如段错误（Segmentation Fault）或浮点异常（Floating Point Exception）。\u003C/li\u003E\u003Cli data-list\u003D\"bullet\"\u003E\u003Cspan class\u003D\"ql-ui\" contenteditable\u003D\"false\"\u003E\u003C/span\u003E未定义结果：在某些情况下，程序可能不会崩溃，但会产生未定义的结果。这种行为是不可预测的，可能会导致程序逻辑错误或其他意外行为。\u003C/li\u003E\u003Cli data-list\u003D\"bullet\"\u003E\u003Cspan class\u003D\"ql-ui\" contenteditable\u003D\"false\"\u003E\u003C/span\u003E编译器优化：现代编译器可能会在编译时检测到除零操作，并生成警告或错误。在某些情况下，编译器可能会优化掉这部分代码，导致程序行为不符合预期。\u003C/li\u003E\u003C/ol\u003E\u003Cp\u003E\u003Cbr\u003E\u003C/p\u003E\u003Ch2\u003E如何检测到除零\u003C/h2\u003E\u003Ch3\u003E仿真中除零检测\u003C/h3\u003E\u003Cp\u003E整数类型除以零会触发“溢出时绕回”诊断警告，提示“出现除以零。商已饱和。”\u003C/p\u003E\u003Cp\u003E浮点数类型除以零默认不会警告，通过Simulink\u003Cstrong\u003E模型设置\u003C/strong\u003E-\u003Cstrong\u003E诊断\u003C/strong\u003E-\u003Cstrong\u003E数据有效性\u003C/strong\u003E，开启“\u003Cstrong\u003E模块输出Inf或NaN\u003C/strong\u003E”，可以配置为触发警告或错误。\u003C/p\u003E\u003Ch3\u003E生成代码除零检测\u003C/h3\u003E\u003Cp\u003E通过模型顾问（Model Advisior）的模型检查功能实现\u003C/p\u003E\u003Cp\u003EMAB、JMAAB中都有“\u003Cstrong\u003E检查Simulink中是否存在除以零的情况\u003C/strong\u003E”检查项\u003C/p\u003E\u003Cp\u003E通常在模型层面就应该发现并解决除零问题，当然，在后续的静态代码检查阶段，利用QAC（Quality Assurance Compiler）或PolySpace的Bug Finder和Coder Prover依然可以检测出除零问题\u003C/p\u003E\u003Cp\u003E\u003Cbr\u003E\u003C/p\u003E\u003Ch2\u003E代码生成编译器优化\u003C/h2\u003E\u003Cp\u003ESimulink生成代码默认会对整数除零保护进行优化，例如unit8类型除以0生成的代码中会直接赋值为MAX_uint16_T，即65535。\u003C/p\u003E\u003Cp\u003E这虽然可以防止程序直接崩溃，但依然会导致程序非预期的行为。\u003C/p\u003E\u003Cp\u003E在Simulink\u003Cstrong\u003E模型设置\u003C/strong\u003E-\u003Cstrong\u003E代码生成\u003C/strong\u003E-\u003Cstrong\u003E优化\u003C/strong\u003E-\u003Cstrong\u003E高级参数\u003C/strong\u003E，可以设置开启“\u003Cstrong\u003E删除防止除法算术异常的代码\u003C/strong\u003E”，此时代码生成编译器不再添加整数类型除零保护代码，遇到整数除零BUG程序直接崩溃。\u003C/p\u003E\u003Cp\u003E\u003Cbr\u003E\u003C/p\u003E\u003Ch2\u003E如何正确处理除零\u003C/h2\u003E\u003Cp\u003ESimulink生成代码的除零保护只能避免程序直接崩溃，依然可能导致程序出现非预期的行为。\u003C/p\u003E\u003Cp\u003E模型设计阶段，在使用Product模块（Divide模块）进行除法运算时，应提前考虑除数为零的情况，并进行针对设计。\u003C/p\u003E\u003Cp\u003E此外，使用\u003Ca href\u003D\"https://simulink.wiki/t/593b1e0b62497c427974373e5f07\" rel\u003D\"nofollow\"\u003ESaturation模块\u003C/a\u003E限制涉及除法运算的局部运算结果的上、下限值可以一定程度缓解除零导致的数值急剧增大导致的异常，尤其是当除零只是瞬态时。\u003C/p\u003E\u003Ch3\u003E滑移率计算除零处理示例\u003C/h3\u003E\u003Cp\u003E在ABS/ESC控制器开发中，滑移率是非常关键的参数，其计算公式为：\u003C/p\u003E\u003Cp\u003E(车速-轮速)/车速×100%\u003C/p\u003E\u003Cp\u003E当车速为零时，上述计算会面临除零情况，鉴于车速很低时已经无需ABS介入，我们可以先判断车速是否大于某个阈值，例如1km/h，当车速大于阈值时使用公式计算滑移率，当车速小于阈值时，直接输出默认值，例如0%\u003C/p\u003E\u003Cp\u003E通过\u003Ca href\u003D\"https://simulink.wiki/t/2501291d62497c42787408164434\" rel\u003D\"nofollow\"\u003ESwitch模块\u003C/a\u003E可以实现上述功能，我们在Switch模块后端再添加一个Saturation模块，限制滑移率输出范围为0～1，进一步提高模型生成代码的健壮性。\u003C/p\u003E',ipRegion:'',updatedByUid:1,createdAt:'2025-04-20 17:17:55',updatedAt:'2025-04-20 17:36:58',mentionNum:0,mentionedBy:[],mentionUsers:[],likeUsers:[],},],usersMap:new Map([[1,{uid:1,url:'/u/5b180a1c62497c417c6940494325070c',avatar:'/a/5b180a1c62497c417c6940494325070c',username:'Simulink',}],]),related:[{title:'Simulink Sum of Elements，Simulink Sum of Elements模块',url:'/d/041d2b3162497c417c69415404660778462a0027',},{title:'Simulink Sum模块上下翻转，Simulink Sum模块输入的位置，Simulink Sum里面加减号位置',url:'/d/0d60273e62497c417c6941540466067824325920',},{title:'Simulink Sum方向，Simulink Sum模块怎么旋转，Simulink Sum模块怎么改变方向',url:'/d/0121380562497c417c694154046605781e4e6432',},{title:'Simulink Sum 模块简介',url:'/d/59030a0a62497c417c694154046604783539463e',},{title:'Simulink Gain模块旋转，Simulink Gain怎么变方向',url:'/d/26172f0b62497c417c69415404610d7818177135',},{title:'Simulink Unary Minus模块简介',url:'/d/5b18031f62497c417c69415404610378033a5f36',},{title:'Simulink Gain模块作用，Simulink Gain模块参数设置，Simulink Gain模块设置变量，Simulink Gain模块怎么设置kp',url:'/d/161f343c62497c417c694154046101782d2e663d',},{title:'Simulink Gain模块简介',url:'/d/013d094262497c417c694154046100780e0f645d',},{title:'Simulink Divide，Simulink Divide模块，Simulink Divide block',url:'/d/3937204a62497c417c6941540461067811164200',},{title:'Simulink Product除法，Simulink Product模块除法，Simulink Product */',url:'/d/2e61021c62497c417c6941540461057830197808',},{title:'Simulink Product模块作用，Simulink Product怎么用，Simulink Product用法，Simulink Product模块用法',url:'/d/37045c2262497c417c69415404610478363b7f34',},{title:'Simulink Product 模块简介',url:'/d/3518091962497c417c69415404600d78364a6e37',},{title:'Simulink Data Type Conversion模块的2个典型应用场景',url:'/d/3927263c62497c417c69415404600c781c345110',},{title:'Simulink Data Type Conversion模块简介',url:'/d/5e060b2462497c417c69415404600378072e551d',},{title:'给Simulink Constant模块赋值的3类方法',url:'/d/2b15364162497c417c694154046002782c28472a',},{title:'Simulink Constant模块简介',url:'/d/391f041962497c417c6941540460007804156536',},{title:'Simulink From怎么找Goto',url:'/d/181a224162497c417c69415404600578324c0434',},{title:'Simulink Goto模块颜色，Simulink Goto高亮，Simulink Goto品红色阴影边框、青色背景怎么恢复颜色',url:'/d/1835252862497c417c694154046004782d4c710e',},{title:'Simulink Goto Tag Visibility模块，Simulink Goto模块 作用域，Simulink Goto模块 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