[feature] Add more base routines for stdlib_linalg

[zoziha]

Description

Fortran has its unique grammatical characteristics. I think it is impossible to learn from some routines of Matlab and Python completely. We should be based on the characteristics of Fortran.
Seeing the implementation of linspace/logspace in stdlib_math, I want to implement some routines in stdlib, mainly for stdlib_linalg.

Tasks

• zeros (see [stdlib_linalg] Add zeros, ones function. #478)
• ones (see [stdlib_linalg] Add zeros, ones function. #478)
• seq/arange (see [stdlib_math] Add arange function. #480)
• eye, for matrix is not square. (see [stdlib_linalg] Update eye function. #481)
• det (need BLAS Interfaces and wrappers: BLAS #450 )
• diff (see [stdlib_math] Add function diff #605 )

---

• is_square
• is_symmetric

Prior Art

Some routines has been implemented in keurfonluu/Forlab (MIT license).
I will rethink how to adapt to Fortran to write code.

[ghbrown]

I was thinking about proposing and implementing some matrix property checks like

• is_square (not sure if it's the same is is_squared?)
• is_symmetric
• is_triangular (upper, lower, and diagonal can fit in here somewhere)
• is_hermitian
• is_hessenberg (upper, lower, etc.)
  etc.

I think there is at least a little bit about API to discuss here, since for example I have found it very useful for is_square to also set the dimension n. Also, there should be a very clean way to set the API for checks that can result in upper/lower/diagonal/none, but we could discuss what is best for everyone.

I can open an issue to discuss this if that works for you.