set term png transparent size 480, 360 \
        xffffff x000000 x404040  \
        xff0000 x0000ff x25bc24 x8e00ba x5f3e1a

set output '/dev/null'
set title 'Fig5a'
plot 'fig5a_corr.data' w l
set output 'fig5a.png'
replot

set output '/dev/null'
set title 'Fig5b'
plot 'fig5b_corr.data' w l
set output 'fig5b.png'
replot

set output '/dev/null'
set title 'Fig6a'
plot 'fig6a_corr.data' w l
set output 'fig6a.png'
replot

set output '/dev/null'
set title 'Fig6b'
plot 'fig6b_corr.data' w l
set output 'fig6b.png'
replot