::  Posts  ::  RSS  ::  ◂◂RSS  ::  Contact

Simple Plotting Software?

October 12th, 2011
tech  [html]
When trying to understand data, looking at it in graphical form is incredibly useful. When looking at raw data it is difficult to get a sense of the overall patterns. Summary statistics can be misleading. Yesterday I wanted to look at some data. My graphing process was:
    # prepare data on the command line into a stream of lines as "xval yval"
    $ emit_data | head -n 3
    4 7
    8 9
    2 200

    # use awk to send the xvals to one file and the yvals to another
    $ (emit_data | awk '{print $1}' | tr '\n' ' ' ; echo) > xvals.txt
    $ (emit_data | awk '{print $2}' | tr '\n' ' ' ; echo) > yvals.txt

    # in octave open the files as two vectors and plot them
    $ octave
    > xvals = load("xvals.txt");
    > yvals = load("yvals.txt");
    > plot(xvals, yvals);

As you can tell, this is annoying. I would prefer to be able to simply write:

    $ emit_data | plot

Is there a program that can do this?

Update 2011-10-12: Adam Yie writes that gnuplot can do what I want:
   emit_data | gnuplot -persist -e "plot '-'"
I've now added an alias to my ~/.bash_profile:
  alias plot='gnuplot -persist -e "plot '\'-\''"'

Some other features that would be nice, and that I would probably include if writing this myself:

  • interpret single column data as if it were the output of "emit_data | cat -n"
  • if given filenames instead of standard input, plot them on the same chart ( plot <(emit_data_a) <(emit_data_b))
  • allow non-numeric X vals
  • interpret data in the format 'YYYY-MM-DD" as dates

Further, it would be nice to be able to specify some options, though I definitely don't want them required:

  • points vs lines
  • x and y ranges
  • chart width and height
  • colors
  • output file if not for display
  • interpret the xvalues as seconds since 1970-01-01

I would probably write this with gnuplot as a backend, and with aquaterm as the mac display terminal (so I wouldn't need to start X11).

Comment via: google plus, facebook

Recent posts on blogs I like:

Absolute scale corrupts absolutely

The Internet has gotten too big. Growing up, I, like many computery people of my generation, was an idealist. I believed that better, faster communication would be an unmitigated improvement to society. "World peace through better communication,"…

via apenwarr August 19, 2019

Traces

At naptime Anna listens to recordings of novels recorded by Jeff’s grandmother. It is the main way she will know Winnie, as it is the main way I have ever known Winnie. Some of the recordings are missing parts, and Suzie often fills in the first few sente…

via The whole sky August 18, 2019

One Night Ultimate Werewolf

I really like One Night Ultimate Werewolf (ONUW), and recommend trying it out. The Daybreak expansion is also good (but I’d skip the later games in the series). App For those who’ve played a lot and wish the night took 20 seconds rather than a few minutes…

via The sideways view August 18, 2019

more     (via openring)

More Posts:


  ::  Posts  ::  RSS  ::  ◂◂RSS  ::  Contact