roots-fortran

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Vectorized interface

1

It could be nice to support a vector-instruction-friendly interface. There is an open issue for this in https://github.com/scipy/scipy/issues/7242. The purpose is to solve a family of problems: $$f(x_k,p_k) = 0,...

ivan-pi

Robust sign comparison

2

https://github.com/jacobwilliams/roots-fortran/blob/60524bc4f491a50ae1b2e538e1e486551812b9db/src/root_module.F90#L1837 I noticed the sign comparison is performed inconsistently; i.e. in some places as `fa*fc < 0` and in some places you extract the sign explicitly like above. The latter...

ivan-pi

Passing external parameters to functions

3

Hi, Thanks for making these codes available. I'm trying to find a way to pass additional parameters (beisdes the argument) to the objective function, eg instead of f(x) have f(x,...

giannilmbd

Add methods that require derivatives

2

e.g, Newton-Raphson, Halley.

jacobwilliams

Is there any interest to have custom termination conditions? This could be implemented with a user-provided callback (procedure pointer). If nothing else it could be useful for comparison with other...

ivan-pi

Robust bisect

4

https://github.com/jacobwilliams/roots-fortran/blob/60524bc4f491a50ae1b2e538e1e486551812b9db/src/root_module.F90#L2524 The excerpt below is taken from Kahaner, Moler, & Nash, Numerical Methods and Software, 1989, Prentice-Hall, Inc.:  According to [Herbie](https://herbie.uwplse.org/) this rearrangement seems irrelevant in FP64, however I...

ivan-pi

Use nopass to simplify the interface for the user-defined function

3

The abstract interface func has two arguments, "me" of type "class(root_solver)" and the proper argument of the function. The first serves no purpose for the evaluation of the function and...

arjenmarkus

If so, some preliminary work on prior art can be found [at this comment](https://github.com/fortran-lang/stdlib/issues/87#issuecomment-755596293) and below.

epagone