set term pngcairo size 1024,768
# set output 'slab.png'
  set output '| ffmpeg -y -r 15 -f image2pipe -i - -vcodec libx264 -profile:v baseline -pix_fmt yuv420p slab.mp4'
  set colors classic
  set encoding utf8
  set minussign

  TimeBetSnapshot = 0.1

  unset key
  set xlabel 'x'
  set ylabel 'u'
  set yrange [0:2.5]

  template = 'output_%03d.txt'

  n = 1000
  do for [i=0:n] {
    filename=sprintf(template,i)
    print filename
    time = sprintf('t = %4.1f',i*TimeBetSnapshot)
    set label 1 time at graph 0,1 offset 2,-1.5
    plot \
      for [j=0:i:100] filename2=sprintf(template,j), filename2 u 6:5 w d lt 1 lc rgb '#ffcccc', \
      filename u 6:5 w d lt 1 lc rgb '#0000ff'
  }