Can I plot 1D heatmap with gnuplot?

Question

I'm trying to plot a 1D heatmap using two columns of data (x value and y value) in gnuplot. The linegraph plotted using my data is like this:

Linegraph:

However after some trying I can only achieve this:

What I've got:

And what I want to get is something like this. (Only example)

What I want:

The gnuplot script that I use is as follows:

set view map
set size ratio 0.2
unset ytics
unset key
splot 'test.dat' u 1:(1):2 palette

Could anyone help please?

Answer 1

I would do it like this:

unset key
set xrange noextend
set offset 0,0,graph .05,graph .05
set palette cubehelix negative

plot 'foo.dat' using 0:3 with lines lc "black", \
     'foo.dat' using 0:(70):3 with lines lc palette lw 10