[R] How to calculate the derivatives at each data point?

[konstantinos christodoulou]

Hi Ivan!

Thank you for your valuable insights! I look forward to learning more about
numerical differentiation and about this subject.

The pracma package and the fornberg() function is impressive. I got some
really good approximations on my derivatives.

Thank you!
Kostas

On Tue, Jan 31, 2023 at 12:18 PM Ivan Krylov <krylov.r00t using gmail.com> wrote:

> В Tue, 31 Jan 2023 11:16:21 +0200
> konstantinos christodoulou <konstantinos.christodoulou1 using gmail.com>
> пишет:
>
> > How can I find the derivatives of the atmospheric measurements at each
> > altitude?
>
> Welcome to the world of finite difference methods! If you can find a
> good textbook on them, it may be a good idea to skim it.
>
> pracma::fornberg() will give you a numerically stable approximation
> (otherwise the Vandermonde matrix required to obtain the Taylor series
> coefficients may get hard to solve) to the derivative values you're
> interested in, but do note that they are only approximations. In
> particular, there's less information for the values at the ends of
> the altitude range than for the points in the middle.
>
> >       [[alternative HTML version deleted]]
>
> P.S. Please compose your messages to R-help in plain text:
> https://www.r-project.org/posting-guide.html
> https://stat.ethz.ch/pipermail/r-help/2023-January/476845.html
>
> --
> Best regards,
> Ivan
>

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