GNUPLOT Each Histogram Bar with different color

问题:

I want to visualize the amount of different colors of a bitmap file.

My Datasheet looks like:

1 163073164 4 185122087 3 255242000 8 255255255 3 000162232 1 181230029 1 127127127 1 136000021 3 200191231 

I want to draw each color bar with its own color by using gnu plot histogram style.

I just try something out by using "lc variable" but it doesnt work. :-(

My GNUPLOT script by now:

set style data histograms  set boxwidth 1 set grid set style histogram cluster gap 0   set style fill solid 1.0 border -1 set yrange [0:*] set xrange [0:*] set xtics border in scale 0,10  nomirror rotate by -45  offset character 0, 0, 0 left plot "histo.dat" using 1:xticlabels(2) lc variable no title #EOF 

I've got this error message:

gnuplot> plot "histo.dat" using 1:xticlabels(2) lc variable no title                                               ^          "histo.plt", line 9: Bad data on line 1 

Can anybody give me a hint or the correct commands?

Best regards Robert

回答1:

Nice question. I've managed to make it work using the boxes style as opposed to the histogram style you were originally using. I don't think that should make too much of a difference though:

set boxwidth 1 set grid set style fill solid 1.0 border -1 set yrange [0:*] set xrange [-.5:*] set xtics border in scale 0,10  nomirror rotate by -45   plot "histo.dat" using ($0):1:($0):xticlabels(2) w boxes lc variable notitle                         #^boxes centered on 0,1,2,3,....                            #^data column                               #^ linecolor column.  first box has linecolor corresponding to ls 0, second box has linecolor corresponding to ls 1, etc ...                                    #^ xticlabels (apparently) come last. 

If you're unfamiliar with pseudo-column 0, it is (essentially) the line number in the datafile. I don't usually post the output of these things, but this makes one very colorful plot!

回答2:

I just edit something and now it works.

set boxwidth 1 set grid set style fill solid 1.0 border -1 set yrange [0:*] set xrange [-.5:*] set xtics border in scale 0,10  nomirror rotate by -45 left plot "histo.dat" using ($0):1:($2):xticlabels(3) w boxes lc rgb variable notitle                         #^boxes centered on 0,1,2,3,....                            #^data column                               #^ linecolor column.  first box has linecolor corresponding to ls 0, second box has linecolor corresponding to ls 1, etc ...                                    #^ xticlabels (apparently) come last.  

文章来源: GNUPLOT Each Histogram Bar with different color