gnuplot - plot different blocks with different color

Question

I have a data like this in a file.dat

2 2
5 5
7 3

100 102
130 80
116 134

-40 -100
-50 -60
-61 -58

I would want to plot each block in different color,

There is no restriction that a specific color, but just some visually different color.

I tried with linetype like this:

for [IDX=0:2] 'file.dat' i IDX u 1:2 with linespoints linetype IDX

it plots all the blocks with different color and obviously only last one is visible.

So what is the right way to do this?

Answer 1

That is the right way, but you must have two blank lines in order to access different blocks with index.

And, you should start at linetype 1, because linetype 0 is a special linetype for the grid lines:

2 2
5 5
7 3


100 102
130 80
116 134


-40 -100
-50 -60
-61 -58

And the plot command

plot for [IDX=0:2] 'file.dat' index IDX u 1:2 with lp lt IDX+1