Plotting different columns on the same file using boxes

Question

I have a file that looks like

$cat myfile.dat

1 8 32 19230 1.186 3.985
1 8 64 9620 0.600 7.877
1 8 128 4810 0.312 15.136
1 8 256 2410 0.226 20.927
1 8 512 1210 0.172 27.708
1 8 1024 610 0.135 35.582
1 8 2048 310 0.121 40.172
1 8 4096 160 0.117 43.141
1 8 8192 80 0.112 44.770
.....
2 8 16384 300 0.692 6.816
2 8 32768 150 0.686 6.877
2 8 65536 80 0.853 5.904
2 10 320 7830 1.041 4.575
2 10 640 3920 0.919 5.189
2 10 1280 1960 0.828 5.757
2 10 2560 980 0.773 6.167
2 10 5120 490 0.746 6.391
2 10 10240 250 0.748 6.507
2 10 20480 130 0.770 6.567
....
3 18 8192 10 1.311 12.759
3 20 32 650 1.631 3.978
3 20 64 330 0.838 7.863
3 20 128 170 0.483 14.046
3 20 256 90 0.508 14.160
3 20 512 50 0.559 14.283
3 20 1024 30 0.665 14.405
3 20 2048 20 0.865 14.782
3 20 4096 10 0.856 14.932
3 20 8192 10 1.704 14.998

As you can see, there are many ways of plotting this information depending on the column we want as x axis. One of the ways I would like to plot the information is the 6th against the 1st column

p "myfile.dat" u 1:6

enter image description here

My main questions is if there is a way to plot those bars as solid boxes since we are only interested in the peak value achieved and not the frequency or density region of the dots.

Christoph · Accepted Answer · 2013-08-14 18:51:34Z

2

Gnuplot has the smooth option, which can be used e.g. as smooth frequency to sum all y-values for the same x-value. Unfortunately there is no smooth maximum, which you would need here, but one can 'emulate' that with a bit of tricking in the Using statement.

reset
xval = -1000
max(x, y) = (x > y ? x : y)
maxval = 0
colnum = 6

set boxwidth 0.2

plot 'mydata.dat' using (val = column(colnum), $1):\
     (maxval_prev = (xval == $1 ? maxval : 0), \
      maxval = (xval == $1 ? max(maxval, val) : val),\
      xval = $1, \
      (maxval > maxval_prev ? maxval-maxval_prev : 0)\
     ) \
     smooth frequency lw 3 with boxes t 'maximum values'

Every using entry can consist of different assignments, which are separated by a comma.

If a new x value appears, the variables are initialized. This works, because the data is made monotonic in x by smooth frequency.

If the current value is bigger than the stored maximum value, the difference between the stored maximum value and the current value is added. Potentially, this could result in numerical errors due to repeated adding and subtracting, but judging from you sample data and given the resolution of the plot, this shouldn't be a problem.

The result for you data is: enter image description here

answered Aug 14, 2013 at 18:51

Christoph

48.7k8 gold badges94 silver badges198 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

Manolete Over a year ago

@_Christoph: Thanks for that. It is indeed very useful to know how to calculate maximums.

choroba · Accepted Answer · 2013-08-14 13:40:58Z

1

You can search for the maximum and plot only that, but this is probably easier, even if it draws lots of boxes one over another:

plot "myfile.dat" using 1:6:(.1) with boxes fillstyle solid

answered Aug 14, 2013 at 13:40

choroba

245k27 gold badges221 silver badges304 bronze badges

2 Comments

Manolete Over a year ago

@_choroba what exactly is the :(.1) doing?

choroba Over a year ago

@Manolete: The third number specifies the width of the boxes.

Collectives™ on Stack Overflow

Plotting different columns on the same file using boxes

2 Answers 2

1 Comment

2 Comments

Your Answer

Linked

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

1 Comment

2 Comments

Your Answer

Sign up or log in

Post as a guest

Linked

Related