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内嵌函数
编程
计算控制
Update
Usage
•
Update[
symbol
]
告诉
Mathematica
已经出现能够
影响和一个符号相关的值的隐式变化。
•
Update[
]
指定可以影响任何符号值。
Notes
•
Update
处理内部优化特征。除了在实际中很少出现的一些特殊情况外,它不必被调用。
• 一个特殊情况是在一个符号值中的变化可以通过改变测试
Condition
的结果影响另一个符号的值。
• 使用
Update
从来不会给你带来错误结果,尽管它会降慢系统的运行。
• 参见
Mathematica
全书
:
节
2.5.12
.
THIS IS DOCUMENTATION FOR AN OBSOLETE PRODUCT.
SEE THE
DOCUMENTATION CENTER
FOR THE LATEST INFORMATION.