Where is error here?

[DanRRRR]

The first line below not only does not work with no reason, it also gives superconfusing diagnostics
"Input deck line number 0 Incorrect number of arguments".
Truly the error from the hell.
If substitute this line with the second line -- all works fine but this is not what was needed

1. number_density = if( (x gt -1.) and (x lt 1.), den_gas * (1. + (y/gradL)^2 ), 0.)
2. number_density = if( (x gt -1.) and (x lt 1.), den_gas, 0.)

The whole input.deck is shown below

begin:control

  nx =  1280
  ny =  768

  t_end = 0.1 * nano

# Size of domain
  x_min = -160. * micron
  x_max =  160. * micron
  y_min = -96. * micron
  y_max =  96. * micron
  stdout_frequency=100
end:control

#-------------------------------------
begin:boundaries
  bc_x_min = simple_laser
  bc_x_max = simple_outflow
  bc_y_min = simple_outflow
  bc_y_max = simple_outflow
end:boundaries

begin:window
   move_window = T
#   window_v_x = 3.0e8
    window_v_x = 0.9989*c
   window_start_time = 9.0e-13
   bc_x_min_after_move = simple_outflow
   bc_x_max_after_move = simple_outflow
end:window

#-----------------------------------------------------
begin:constant
  laser_wavelength = 0.8 * micron
  omega = 2 * pi * c / laser_wavelength

  n_crit = critical(omega)
  ne_max = 0.5 * n_crit

  laser_k = 2 * pi / laser_wavelength
  den_gas = 0.00005 * n_crit
  Hcharge  = 1
  Ncharge  = 1

  GradL = 40 * micron
  HoleDep = 1.

  r = sqrt(y^2 + z^2)
#  z = 0

  laser_angle = 0 # pi / 4
  laser_fwhm   = 15 * micron  #  / (2.0 * sqrt(loge(2.0)))
  laser_dur_fwhm = 50.e-15
  yShift = 0.

end:constant

 begin:collisions
  use_collisions = T
  use_nanbu = T
  coulomb_log = auto
#  collisional_ionisation = T
#  collide = electron electron on
  coll_n_step = 10
  collide = all
end:collisions

#------------------------------------------------
begin:species
  name = Hydrogen
  charge = Hcharge
  mass   = 1836.2

  number_density = if( (x gt -1.) and (x lt 1.), den_gas * (1. + (y/gradL)^2 ), 0.)
#  number_density = if( (x gt -1.) and (x lt 1.), den_gas, 0.)

   npart_per_cell = 1
end:species
#---------------------------------------------------
begin:species
  name = Nitrogen
  charge = Ncharge
  mass = 1836.2*14.
  number_density = number_density(Hydrogen) * 0.1
  npart_per_cell = 1
end:species

#---------------------------------------------------
begin:species
  name = electron
  charge = -1.0
  mass = 1.0
  number_density = number_density(Hydrogen)*Hcharge  + number_density(Nitrogen)*Ncharge
  npart_per_cell = 4

end:species

#--------------------------------------------------

begin:laser
  boundary = x_min
  intensity_w_cm2 =  2.e19
  profile = gauss(y, -yShift, laser_fwhm)
  t_profile = gauss(time, 4.*laser_dur_fwhm, laser_dur_fwhm * (2.0 * sqrt(loge(2.0))))
  pol_angle = 0. # 0.5*pi      # S-polarization
  lambda = laser_wavelength
end:laser
#....................

#================= O U T P U T ====================

begin:output
  name = normal
  file_prefix = p

# Simulated time between output dumps
  dt_snapshot = 250 * femto

# Properties on grid
  grid = always
  ex = always
  ey = always
#  bz = always


end:output
                                          

[Status-Mirror]

  GradL = 40 * micron
  number_density = if( (x gt -1.) and (x lt 1.), den_gas * (1. + (y/gradL)^2 ), 0.)

EPOCH input deck is case-sensitive, and you go from GradL to gradL.

Cheers,
Stuart

P.S.: I will admit the error message could have been more helpful here!

[DanRRRR]

Oh, not again with that upper/lower cases...Thanks Stuart!
But please take this good example to improve diagnostics, such cases take a lot of blood from users