Yambo Community Forum

Dear All

I have problem with ypp command. I explain what I do and I will be happy
if some one help me in my problem:

1. I have 'scf' and 'nscf' by running 'pwscf'

2. with the use of command 'p2y -S -N' I have inputs of yambo.

3. to have outputs of yambo which are the solution of KS equation I do below:
a:localhost>yambo
b:localhost>yambo -e -o b -y h
c:localhost>yambo
and at the end I have outputs of yambo or in fact 'absorption energy'.

4.Now I want to run ypp. I run some commands but no result.
a:localhost>ypp -H 'gives help for ypp commands'
___ __ _____ __ __ _____ _____
| Y || _ || Y || _ \ | _ |
| | ||. | ||. ||. | / |. | |
\ _/ |. _ ||.\ / ||. _ \ |. | |
|: | |: | ||: | ||: | \|: | |
|::| |:.|:.||:.|:.||::. /|::. |
`--" `-- --"`-- --"`-----" `-----"

Tool: ypp 3.2.1 rev.448
Description: Y(ambo) P(ost) P(rocessor)

-h :Short Help
-H :Long Help
-J <opt> :Job string identifier
-V <int> :Input file verbosity
-F <opt> :Input file
-I <opt> :Core I/O directory
-O <opt> :Additional I/O directory
-C <opt> :Communications I/O directory
-N :Skip MPI initialization
-S : DataBases fragmentation
-k <opt> :BZ Grid generator [(k)pt,(q)pt,(l)ongitudinal]
-e <opt> :Excitons [(s)ort,(a)mplitude,(w)ave]
-l <opt> :Electrons [(w)ave,(d)ensity]
-f :Free hole position [excitons plot]
-r :BZ energy RIM analyzer

By YAMBO developers group
http://www.yambo-code.org

b: Then I type in llocalhost 'ypp -F' to make input

ypp : invalid option -- F

This is ypp 3.2.1 rev.448
Usage: ypp -h -H -J <opt> -V <int> -F <opt> -I <opt> -O <opt> -C <opt> -N
-S -k <opt> -e <opt> -l <opt> -f -r
Try `ypp -H' for more information

I run other commands you can see top. but I couldn't have input

***I do not know what is <opt> and how I can make input.
***Are these stages true?
***what are the commands for making inputs and running ypp to have outputs
and plot the results.

please help me

Best wishes
enorouzi

Dear Enorouzi,
first of all let me ask you to fill your signature with your affiliation in the profile.

3. to have outputs of yambo which are the solution of KS equation I do below:
a:localhost>yambo
b:localhost>yambo -e -o b -y h
c:localhost>yambo
and at the end I have outputs of yambo or in fact 'absorption energy'.

Here be careful, this is not the solution of the KS equation (you have just calculated it with pwscf!!)
Beside the "-e" that I do not recognize, in this way you are solving the Bethe Salpeter equation and
you maybe you can have a look at the manual.

4.Now I want to run ypp. I run some commands but no result.

***I do not know what is <opt> and how I can make inpu

It depends on what do you want to calculate or visualize. If you want to plot spectra coming from the
yambo output you don't' need it, but you should have the yambo output files in your directory and
you can plot them for instances using "gnupiot".

If you want to visulaize wave functions, excitonic wavefunctions etc,
than this shoud be clear:
-e <opt> :Excitons [(s)ort,(a)mplitude,(w)ave]
-l <opt> :Electrons [(w)ave,(d)ensity]

so ypp -l w
produce the input for plotting the KS wave function.
If you want to plot excitonic wave functions you need to diagonalize your excitonic matrix and
store the eigenvector.
You can find some information for ypp in the tutorial.

The -F is needed just to redirect the input.