[Pw_forum] set_irr sets incorrect npert when trans=.false. and elph=.true.

[Alaska Subedi]

Dear All,

I would like to calculate lambda using different sets of dense k
points for double delta integration. In order to do so I calculate
dvscf using the following ph.in file:

--
&inputph
  tr2_ph = 1.0d-16
  prefix='Al-ep2',
  fildvscf='dvscf'
  amass(1) = 26.98
  outdir = './tmp/'
  fildyn = 'Al-ep0.dyn2'
/
   -0.250000000000000E+00   0.250000000000000E+00   -0.250000000000000E+00

I now want to use dvscf and dyn files generated from this run to
calculate lambda. For this, I use the following input file:

--
&inputph
  tr2_ph = 1.0d-16
  prefix='Al-ep2',
  fildvscf='dvscf'
  amass(1) = 26.98
  outdir = './tmp/'
  fildyn = 'Al-ep0.dyn2'
  elph=.true.
  trans=.false.
/
   -0.250000000000000E+00   0.250000000000000E+00   -0.250000000000000E+00


However, the code  crashes with the error:
forrtl: severe (41): insufficient virtual memory

After some debugging, I noticed that npertx is very large and the
error happens when matrices of dimension npertx is being allocated in
allocate_pert(). npertx is calculated as:

       DO irr = 1, nirr
           npertx = max (npertx, npert (irr) )
        ENDDO

The error occurs because npert has incorrect values assigned in the
subroutine set_irr.

This error does not occur when I calculate phonon and lambda in the
same run (using trans=.true. and elph=.true.).

Any pointer to fix this error would be greatly appreciated.

Thanks,
Alaska

The scf file is:&control
    calculation='scf'
    restart_mode='from_scratch',
    tprnfor = .true.
    prefix='Al-ep2',
    pseudo_dir = './pseudo/',
    outdir='./tmp/'
/

&system
   ibrav=  2,
   celldm(1) =7.5,
   nat= 1, ntyp= 1,
   ecutwfc =45.0,
   occupations='smearing',
   smearing='methfessel-paxton',
   degauss=0.05
/

&electrons
    conv_thr = 1.0d-10
!    diagonalization = 'cg'
!    mixing_mode = 'local-TF'
     mixing_beta = 0.3d0
/

ATOMIC_SPECIES
 Al  26.98 Al.vbc.UPF
ATOMIC_POSITIONS
 Al 0.00 0.00 0.00
K_POINTS {automatic}
  8  8  8  0  0  0