GNU Octave 是一个免费软件包，除其他外，具有函数 polyfit 要做的事 最小二乘多项式曲线拟合。我认为这个（或其他具有等效功能的包）可能比泰勒级数展开更适合您的问题。该绝对值项可能会导致很难找到一个泰勒级数，该级数可以很好地通过 x=0.7 处的点进行推断，其中一阶导数具有不连续性。
GNU Octave is a free package that, among other things, has a function polyfit to do least-squares polynomial curve fitting. I think this (or some other package with an equivalent function) is probably a better match for your problem than Taylor series expansion. That absolute value term might make it hard to find a Taylor series that extrapolates well through the point at x=0.7, where the first derivative has a discontinuity.
This is a C++ library which allows you to write expressions and variables and calculate not only the value but also any order derivative. The compiler is the one generating the code for the derivatives.
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GNU Octave 是一个免费软件包，除其他外，具有函数 polyfit 要做的事
最小二乘多项式曲线拟合。我认为这个（或其他具有等效功能的包）可能比泰勒级数展开更适合您的问题。该绝对值项可能会导致很难找到一个泰勒级数，该级数可以很好地通过 x=0.7 处的点进行推断，其中一阶导数具有不连续性。
GNU Octave is a free package that, among other things, has a function polyfit to do
least-squares polynomial curve fitting. I think this (or some other package with an equivalent function) is probably a better match for your problem than Taylor series expansion. That absolute value term might make it hard to find a Taylor series that extrapolates well through the point at x=0.7, where the first derivative has a discontinuity.
Maxima 就是这样做的。请参阅 taylor 函数。
Maxima does this. See the taylor function.
https://ctaylor.codeplex.com
这是一个 C++ 库，允许您编写表达式和变量并计算不不仅是值，还包括任何阶导数。
编译器是生成导数代码的编译器。
https://ctaylor.codeplex.com
This is a C++ library which allows you to write expressions and variables and calculate not only the value but also any order derivative.
The compiler is the one generating the code for the derivatives.
Wolfram Alpha 将象征性地在网络上免费为您执行此操作。 H/T @ExcessPhase 使用
abs(x)=sqrt(x*x)的想法。Wolfram Alpha will do this for you symbolically for free on the web. H/T @ExcessPhase for the idea of using
abs(x)=sqrt(x*x).