This guidance is written for people who are familiar with the Linux system and have fftw3 libraries which is needed by the FPSEID²¹ package
When you install fftw3, please set the configure option as -enable-openmp. In this page, the manual conducts readers to create three executable modules, ‘cg_exe’, ‘sd_exe’, and ‘tddft_exe’.
 The module ‘cg_exe’ and ‘sd_exe’ perform the static DFT band-structure calculation to genrate initial charge density and wavefunctions under full-grid G-space, which are necessary for the TDDFT time-evolution calculation within the Suzuki-Trotter split operator scheme.
  Finally, the module ‘tddft_exe’ performs electron-ion Ehrenfest dynamics calculations under optical field.
First of all, download "FPSEID21.tar.gz" file from this website, then put this file to your home directory. Hereafter needed commands on Linux system will be displayed in gray background starting with symbol '$'.
Now, type
$ tar xvzf PSEID21.tar.gz
Then a new directory “PSEID21” appears on your home directory.
Move to this directory and type
$ ls
Now you can see three subdirectories as
$ cg_GGA_f_code  sd_GGA_f_compact_code  tddft_f_Avec_compact_multifft
You can make executable load module in each directory.
For an example, please do as followings,
$ cd cg_GGA_f_code
$ chmod 744 make.sh
$ ./make.sh >& make.out
Then you'll find executable module ‘cg_exe’. In case of some trouble, some error messages should be described in a file 'make.out'. The 'make.sh' script uses the 'ifort' compiler with proper compiling option. If user is familiar with ifort compiler and willing to maximize the performance,' or if you wish to use other compliers, please edit 'make.sh' file.
 To fit another manual ‘How to execute?’, this manual recommends you to make directory ‘lm’ in your home directory and move 'cg_exe’ into 'lm’.
Similary, the module 'sd.exe' can be made as follows:
$ cd ..
$ cd sd_GGA_f_comact_code
$ chmod 744 make.sh
$ ./make.sh >& make.out
Then you obtain 'sd_exe'. Again, relocation of 'sd_exe' into 'lm' is recommended.
Finally, you will get 'tddft_exe' just as followings:
$ cd ..
$cd tddft_f_Avec_compact_multifft
but before compiling, you must edit 'make.sh', which now uses mpiifort compiler.
The first line of make.sh is written as
export DIR={your directory where the FFTW3 is installed}
So, you must arrange this part, which might be '/home/appl/FFTW3' or '/home/youraccount/appl/FFTW3' or something else. And please check the directory of the FFTW3 tool has two subdirectories 'lib' and 'include'. These subdirectories are necessary paths for compiling options '-L{$DIR}/lib' and  '-I{$DIR}/include.'　
After editing 'make.sh', do as follwos:
$ chmod 744 make.sh
$ ./make.sh >& make.out
Then you get 'tddft_exe', which is recommended to move to 'lm'.
 That's all how to compile and now you can move to How to run?