			# sample LAMMPS input script for viscosity of 2d LJ liquid
			# Muller-Plathe via fix viscosity

			# settings

			variable x equal 20
			variable y equal 20

			variable rho equal 0.6
			variable t equal 1.0
			variable rc equal 2.5

			# problem setup

			units lj
			dimension 2
			atom_style atomic
			neigh_modify delay 0 every 1

			lattice sq2 ${rho}
			region simbox block 0 $x 0 $y -0.1 0.1
			create_box 1 simbox
			create_atoms 1 box

			pair_style lj/cut ${rc}
			pair_coeff * * 1 1

			mass * 1.0
			velocity all create $t 97287

			fix 1 all nve
			fix 2 all langevin $t $t 0.1 498094
			fix 3 all enforce2d

			# equilibration run

			thermo 1000
			run 5000

			unfix 2

			# turn on Muller-Plathe driving force and equilibrate some more

			velocity all scale $t

			fix 4 all viscosity 100 x y 20

			compute layers all chunk/atom bin/1d y center 0.05 units reduced
			fix 5 all ave/chunk 20 50 1000 layers vx file profile.mp.2d

			# equilibration run

			variable dVx equal f_5[11][3]-f_5[1][3]

			thermo 1000
			thermo_style custom step temp epair etotal press f_4 v_dVx
			run 20000

			# data gathering run
			# reset fix viscosity to zero flux accumulation

			unfix 4
			fix 4 all viscosity 100 x y 20

			variable visc equal -(f_4/(2(step0.005-125)*lx+1.0e-10))/(v_dVx/(ly/2))
			fix vave all ave/time 1000 1 1000 v_visc ave running start 26000

			thermo_style custom step temp f_4 v_dVx v_visc f_vave

			# only need to run for 10000 steps to make a good 100-frame movie

			#dump 1 all custom 100 dump.mp.2d id type x y z vx

			#dump 2 all image 100 image.*.jpg vx type zoom 1.6 adiam 1.2
			#dump_modify 2 pad 5 amap -0.7 0.7 ca 0.0 2 min blue max red

			run 50000

lammps/examples/VISCOSITY/in.mp.2d
1a200588bd4blammm-devel

in.mp.2d
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