Multiwfn forum

Dear Tian,

It seems to me that I have found a problem...
There is a new patch, in which I did not notice performance degradation with Intel Compiler.

0001-Merge-orbderv-routines.patch.txt

Command line for testing:

time echo "1000 10 10 6 32 3,0,0 2 2 32 0,3,0 2 2 32 0,0,3 2 3 0 -1 100 4 1" | tr " " "\n" | OMP_STACKSIZE=200M ./Multiwfn_noGUI H2O.wfn

I set 10 cores (mine PC has Intel(R) Core(TM) i9-10940X CPU @ 3.30GHz), multiplied H2O molecule(H2O.wfn.txt), calculated at HF/def2TZVP level of theory by X and Y axes twice, and by Z axe --- thrice. Then, I integrate electron density. I used 75.434 grid for integration; Number of unique GTFs: 2412.

Timings:
old:

real    0m20.536s
user    3m24.962s
sys     0m0.301s

new:

real    0m20.570s
user    3m25.301s
sys     0m0.280s

I suppose, the difference in timings comings from a different load of the computer between runs.

I also checked my patch with GCC. Unfortunately, the compilation failed. Below, the patch, that fixes this issue, is. Hope, the patch is correct.

0002-Fix-GCC-build.patch.txt

Best,
Igor

Dear Tian,

Thank you so much! And thank you for `ext` directory!

> The 2F2 part of code will not be compiled for Windows version to avoid introducing dependency of C++ compiler, therefore preprocessor directives have been employed for two lines related to 2F2 in Multiwfn.f90.

In the patch below, I dropped these #ifdef's and introduced ext/no2F2.f90 which has the save behavior like ext/no2F2.c. I hope it will reduce the number of #ifdef lines.
But the main part of the patch is related to the implementation of feature evaluation, which I inserted into function.f90. I chose iUserFunc 1303 (the same number now is for setting up fractional calculus in hidden Option 1000)

0001-Implement-evaluation-of-xi-alpha.patch.txt

Best regards,
Igor

Dear Lian,

We almost finished the paper about the new feature based on fractional calculus. Hope, we will submit it soon.

Briefly, I found a way how to apply fractional calculus to the electron density for constructing new ingredients of DFT functionals. In fractional calculus, there are several ways how to compute derivatives with different kernels. And, I want to implement one of these derivatives in the mainline of Multiwfn as a reference implementation.

Best,
Igor

Dear Tian Lu,

Looks like `module function` is continuing to be... So, the parallel compilation of Multiwfn using CMake is broken...

Anyway, there is a patch that makes Multiwfn's compiling possible using CMake >=3.16 under Linux.
0001-Add-compilation-via-CMake.patch.txt

Tested compilers:
- gfortran 9.3.0
- ifort 2021
- ifx 2022

Tested version of CMake:
- 3.16
- 3.22

I used Ubuntu for testing.

I will introduce the support of Windows and MacOS later. Later, I will also update compilation methods, since currently, there is only a very short description about build customizing.

Best regards,
Igor

Dear Tian Lu,

Thank you so much!

I think now old noGUI-related files can be just dropped.

BTW, could you please rename COMPLIATION_METHOD.txt to COMPILATION_METHOD.txt?

Best regards,
Igor

By the way, on the top of this patch, I wrote the CMake build system, so, module-dependency is solved automatically :-) Also, it works fine for Windows (at least, with noGUI version).

Best regards,
Igor

Dear Tian Lu,

Thank you! Your workaround works with gfortran.

Best regards,
Igor

Dear Tian Lu,

Will you incorporate this patch into the official source code of Multiwfn?

Best regards,
Igor

Dear Tian Lu,

There is a new patch for fixing compilation issues for gfortran:0001-Fix-compilation-issues-for-gfortran.patch.txt

With fixing inquire statement issues and applying an OpenMP-related patch, there is no problem building Multiwfn using gfortran.

Best regards,
Igor

Dear Tian Lu,

That is strange... Do you see fileIO module at the end of fileIO.f90?

Best regards,
Igor