PaulXiCao

Building with liburing support fails with the following warnings: ``` ... ccache /usr/bin/cc -DLIBUS_NO_SSL -DLIBUS_USE_IO_URING -DuSocketsC_EXPORTS -I/home/paul/informatik/uSockets/src -std=gnu11 -fPIC -MD -MT CMakeFiles/uSocketsC.dir/src/io_uring/io_loop.c.o -MF CMakeFiles/uSocketsC.dir/src/io_uring/io_loop.c.o.d -o CMakeFiles/uSocketsC.dir/src/io_uring/io_loop.c.o -c /home/paul/informatik/uSockets/src/io_uring/io_loop.c /home/paul/informatik/uSockets/src/io_uring/io_loop.c: In...

Apply rustfmt to exercises

2

The exercises do not conform to the current rustfmt standard, e.g. [error-handling exercise](https://google.github.io/comprehensive-rust/error-handling/exercise.html). Maybe you can discuss if adding a ci job that checks for rustfmt changes makes sense here?

Closes #1536. Proper check for positive definite matrix by checking diagonal entries of intermediate matrix. Added mentioned example from issue as test.

Wouldn't it make more sense to return `false`? It's not obvious to me that comparing dynamically-sized matrices of different size is necessarily a bug. _Originally posted by @Ralith in https://github.com/dimforge/nalgebra/issues/1568#issuecomment-3478437643_...

Hello. The ([current documentation](https://nalgebra.rs/community)) states > If you intend to work on the source code of nalgebra, you should start by forking the repository. Once you are done making modifications...

Closes #136 . This adds the `.cis()` method for `Float` and `Complex`. Adding it as a trait-based method allows for overloading compared to a free standing implementation. The Float version...

Closes #138 . Implemtented explicitly checking for zero values to treat floating-point zeros better. Positive and negative zeros are both treated as the same (positive) zero value. Differentiating between both...

Closes #140 . This introduced the method `Complex::from_real()` as discussed in #140. Alongside a test is added.