If you look at the Debug Messages pane, the answer is spelled out: The variable $multipler is undefined because it's a typo. It should be $multiplier.

如果看一下 Debug Messages 面板，答案就清楚了：变量 $multipler 是未定义的，因为它是一个拼写错误，应该是 $multiplier。

youdao

Based on a preliminary study on the identified multiplier method, it is pointed out in this paper that this method is a unite method of functional transformation in variational principle.

本文通过对已识别拉氏乘子法的初步探讨，指出了已识别拉氏乘子法是变分原理中泛函变换的统一方法。

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I particularly points out that this descending dimension Lagrange multiplier algorithm improves penalty function algorithm and advance accuracy to a certain degree.

特别要指出的是，该算法改进了罚函数法，并在一定程度上比罚函数法更精确。

youdao

And those instructions, by the way, are very simple: they're things like, take the value out of two places in memory, and run them through the multiplier in here, a little piece of circuitry, and stick them back into someplace in memory.

顺便说一句，那些指令非常简单：,他们从记忆存储器中,取出两个位置的结果，在倍增器中运行，一小部分电路，再将它们插回存储器中的某些地方去。

麻省理工公开课 - 计算机科学及编程导论课程节选

These sorts of income streams will offset a portion of your expenses, and should be subtracted out before calculating your multiplier.

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Most estimates of the actual multiplier come out between 1.0 and 1.5, so maybe we are talking about less than a one percent decline from what GDP would otherwise have been.

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And she insisted that "things are not getting out of hand" in local government and that a multiplier was neither necessary or appropriate, because the sector was self-regulated and pay levels were set by local councils.

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