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gnuplot matrix datablock image

I have an ASCII file with multiple datablocks separated by newlines. Each datablock is the same size. I would like to plot each datablock as a separate heat map. I've been trying variations on the following command to plot the first block:

plot data matrix every :::0::0 w image

But gnuplot segfaults with this command. If I delete all datablocks except one, then I can plot that single block with

plot data matrix w image

How should I modify that first command to pick out an individual datablock? In the end, I would like to write a loop to produce individual plots for each datablock.

Solution

  • To my opinion there is a bit confusion about "datablock", "dataset", "data", etc... If your "blocks" are separated by more than one empty line you can address it with index, check help index. If the "blocks" are separated by one line you can address them via every, check help every.

    Code:

    ### plotting "datablocks"
reset session

$Data <<EOD
1  0
0  1


1  1
1  0


0  1
0  0


1  1
0  1
EOD

unset colorbox
set multiplot layout 2,2
    do for [i=0:3] {
        set title sprintf("Block %d",i)
        plot $Data index i matrix w image notitle
    }
unset multiplot
### end of code

    Result:

    enter image description here