Calculate eigenvalue eigenvector in fortran

[baha_tr]

Homework Statement

Hello, I used to use Fortran 70 before and now I started using Fortran 2023, but I think the library usage is a little different. I wonder how we connect the libraries in 2023, I would be happy if you can help me.

Relevant Equations

intel fortran 2023

I wonder how we connect the libraries in 2023

 

[Arjan82]

There is no 'the' libraries, there are many many libraries, what do you want? You can use e.g. LAPACK to compute eigenvalues.

 

[baha_tr]

I just need to find the 4 states after the base state, I think I will use lapack or dsyevx.

 

[DrClaude]

Calling a Fortran 77 library from Fortran 2023 should be straightforward. Calling it as you would if you wrote your program in Fortran 77 should work.

 

[baha_tr]

"Intel MKL ERROR: Parameter 9 was incorrect on entry to DSYEVX". I am getting error code like this

 

[baha_tr]

ı have solved my problem