示例：向求解命令块添加单位

求解命令块 > 示例：向求解命令块添加单位

示例：向求解命令块添加单位

可以为求解命令块添加单位。在计算过程中，请务必确保所使用的单位互相兼容。

1. 定义单摆的长度。

2. 插入求解命令块，定义问题的微分方程，并使用 odesolve 函数求解方程。角 Ɵ 是垂线与单摆之间的角。

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长度 l 和重力常数 g 都有单位：

然而，起始条件和终点没有单位。因此，将出现关于单位兼容性的错误。

3. 为所有的求解命令块组件添加兼容单位。

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4. 定义绘制求解命令块的解的图像所用的值范围。定义具有单位的范围时，您必须使用步长运算符。

5. 绘制求解命令块的解的图像。

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6. 构造求解命令块，然后在给定估值 t=5 s 的情况下，使用 minimize 函数来求出 Ɵ 何时达到最小值。

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估值的单位必须与要最小化的函数的定义兼容。

7. 构造求解命令块，然后在给定估值 t=2 s 和约束 t<4 s 的情况下，使用 maximize 函数来求出 Ɵ 何时达到最小值。

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8. 使用 SIUnitsOf 函数去除极大值点和极小值点中的单位。为使用无单位的竖直标记，需执行此过程。

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9. 在原始绘图上显示极小值点和极大值点。使用竖直标记显示这两个点与时间轴相交的位置。

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