Generating boxplot (candlestick) diagrams (babel or org-plot)

Generating boxplot (candlestick) diagrams (babel or org-plot)

[Karl Voit]

Hi!

I'm new to babel/gnuplot/org-plot and want to generate classic
Boxplot[1] diagrams.

My tests failed so far:

#+TBLNAME: mydata
#+PLOT: title:"Boxplots of mydata" with:candlesticks
| A | B |
|---+---|
| 5 | 5 |
| 5 | 6 |
| 4 | 5 |
| 5 | 6 |
| 2 | 4 |
| 2 | 5 |

... with «org-plot/gnuplot» results in:
#+begin_verse
gnuplot-mode 0.6.0 (gnuplot 4.4) -- report bugs with "C-c C-u"
Starting gnuplot plotting program...Done

#+end_verse

... with nothing else.


#+begin_src gnuplot  :var data=mydata :file output.png
set title "Plot Test"

plot data using 1:2 with candlestick
#+end_src

... results in empty output.png file.


What is the problem here? At least the second method should end up
in an error message or a file with content I guess.

  1. http://en.wikipedia.org/wiki/Boxplot
-- 
Karl Voit

Re: Generating boxplot (candlestick) diagrams (babel or org-plot)

[Eric Schulte]

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Karl Voit <devnull@Karl-Voit.at> writes:

> Hi!
>
> I'm new to babel/gnuplot/org-plot and want to generate classic
> Boxplot[1] diagrams.
>
> My tests failed so far:
>
> #+TBLNAME: mydata
> #+PLOT: title:"Boxplots of mydata" with:candlesticks
> | A | B |
> |---+---|
> | 5 | 5 |
> | 5 | 6 |
> | 4 | 5 |
> | 5 | 6 |
> | 2 | 4 |
> | 2 | 5 |
>
> ... with «org-plot/gnuplot» results in:
> #+begin_verse
> gnuplot-mode 0.6.0 (gnuplot 4.4) -- report bugs with "C-c C-u"
> Starting gnuplot plotting program...Done
>
> #+end_verse
>
> ... with nothing else.
>
>
> #+begin_src gnuplot  :var data=mydata :file output.png
> set title "Plot Test"
>
> plot data using 1:2 with candlestick
> #+end_src
>
> ... results in empty output.png file.
>

In more complex examples like these I would recommend using a gnuplot
code block rather than using Org-plot.  Gnuplot has an extremely
comprehensive built in help system, typing "help boxplot" at the gnuplot
REPL returns the following.

,----
| gnuplot> help boxplot
|  Boxplots are a common way to represent a statistical distribution of values.
|  Quartile boundaries are determined such that 1/4 of the points have a value
|  equal or less than the first quartile boundary, 1/2 of the points have a value
|  equal or less than the second quartile (median) value, etc.  A box is drawn
|  around the region between the first and third quartiles, with a horizontal line
|  at the median value.  Whiskers extend from the box to user-specified limits.
|  Points that lie outside these limits are drawn individually.
| 
|  Examples
| 
|      # Place a boxplot at x coordinate 1.0 representing the y values in column 5
|      plot 'data' using (1.0):5
| 
| ...
`----

Also see the help for "candlestick".  Using this information the
attached Org-mode file generates a candlestick plot using a Gnuplot code
block.


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#+Title: Box-Plots with Gnuplot
#+Options: ^:nil

#+name: sample
| x | box_min | whisker_min | whisker_high | box_high |
|---+---------+-------------+--------------+----------|
| 1 |       2 |           0 |            6 |        4 |
| 2 |       3 |           1 |            7 |        5 |
| 3 |       4 |           2 |            8 |        6 |
| 4 |       5 |           3 |            9 |        7 |
| 5 |       6 |           4 |           10 |        8 |
| 6 |       7 |           5 |           11 |        9 |

#+begin_src gnuplot :var data=sample :results silent
  set xrange [0:7]
  plot data using 1:2:3:4:5 with candlesticks
#+end_src

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Best,

>
>
> What is the problem here? At least the second method should end up
> in an error message or a file with content I guess.
>
>   1. http://en.wikipedia.org/wiki/Boxplot

-- 
Eric Schulte
http://cs.unm.edu/~eschulte/

Re: Generating boxplot (candlestick) diagrams (babel or org-plot)

[Karl Voit]

Hi Eric!

* Eric Schulte <eric.schulte@gmx.com> wrote:
>
> In more complex examples like these I would recommend using a gnuplot
> code block rather than using Org-plot.  

Thought so. Thanks for confirmation.

> Gnuplot has an extremely
> comprehensive built in help system, typing "help boxplot" at the gnuplot
> REPL returns the following.

My gnuplot (Version 4.4 patchlevel 2) returns:

,----
| gnuplot> help boxplot
| Sorry, no help for 'boxplot'
| gnuplot>
`----

gnuplot-doc is installed. Do I miss something else? «help
candlestick» works. Is «boxplot» a part of an additional extension
package?

> Also see the help for "candlestick".  Using this information the
> attached Org-mode file generates a candlestick plot using a Gnuplot code
> block.
>
> #+name: sample
>| x | box_min | whisker_min | whisker_high | box_high |
>|---+---------+-------------+--------------+----------|
>
> #+begin_src gnuplot :var data=sample :results silent
>   set xrange [0:7]
>   plot data using 1:2:3:4:5 with candlesticks
> #+end_src

Your example works like charm at my side. 

And now I also understand the problem I had: I thought that gnuplot
is able to derive min/max whisker min/max from the data columns by
itself.

Well - this is bad news to me since I do not see any reasonable way
to use gnuplot for that purpose. I might need to learn R or
Python/matplotlib :-(

Thanks for your help anyway!

-- 
Karl Voit

Re: Generating boxplot (candlestick) diagrams (babel or org-plot)

[Eric Schulte]

Karl Voit <devnull@Karl-Voit.at> writes:

> Hi Eric!
>
> * Eric Schulte <eric.schulte@gmx.com> wrote:
>>
>> In more complex examples like these I would recommend using a gnuplot
>> code block rather than using Org-plot.  
>
> Thought so. Thanks for confirmation.
>
>> Gnuplot has an extremely
>> comprehensive built in help system, typing "help boxplot" at the gnuplot
>> REPL returns the following.
>
> My gnuplot (Version 4.4 patchlevel 2) returns:
>
> ,----
> | gnuplot> help boxplot
> | Sorry, no help for 'boxplot'
> | gnuplot>
> `----
>
> gnuplot-doc is installed. Do I miss something else? «help
> candlestick» works. Is «boxplot» a part of an additional extension
> package?
>

I'm using gnuplot 4.5 patchlevel 0 which is probably where this
difference comes in.  As I use gnuplot all the time, I find it
worthwhile to track the development head for nice new features such as
this and beautiful pdf plots through pgf/tikz.

>
>> Also see the help for "candlestick".  Using this information the
>> attached Org-mode file generates a candlestick plot using a Gnuplot code
>> block.
>>
>> #+name: sample
>>| x | box_min | whisker_min | whisker_high | box_high |
>>|---+---------+-------------+--------------+----------|
>>
>> #+begin_src gnuplot :var data=sample :results silent
>>   set xrange [0:7]
>>   plot data using 1:2:3:4:5 with candlesticks
>> #+end_src
>
> Your example works like charm at my side. 
>
> And now I also understand the problem I had: I thought that gnuplot
> is able to derive min/max whisker min/max from the data columns by
> itself.
>
> Well - this is bad news to me since I do not see any reasonable way
> to use gnuplot for that purpose. I might need to learn R or
> Python/matplotlib :-(
>

Judging from the help output for boxplot it looks as though the boxplot
option *will* perform these calculations for you, if you are willing to
move to version 4.5 or later.  The only downside of using new features
in gnuplot is that it is noticeably harder to find help through google.

>
> Thanks for your help anyway!

Happy to help!

-- 
Eric Schulte
http://cs.unm.edu/~eschulte/

Re: Generating boxplot (candlestick) diagrams (babel or org-plot)

[Karl Voit]

* Eric Schulte <eric.schulte@gmx.com> wrote:
> Karl Voit <devnull@Karl-Voit.at> writes:
>
> I'm using gnuplot 4.5 patchlevel 0 which is probably where this
> difference comes in.  As I use gnuplot all the time, I find it
> worthwhile to track the development head for nice new features such as
> this and beautiful pdf plots through pgf/tikz.

Glad to know that gnuplot is under active development!

But CSV? ... geesh seriously? ...

>> And now I also understand the problem I had: I thought that gnuplot
>> is able to derive min/max whisker min/max from the data columns by
>> itself.
>>
>> Well - this is bad news to me since I do not see any reasonable way
>> to use gnuplot for that purpose. I might need to learn R or
>> Python/matplotlib :-(
>
> Judging from the help output for boxplot it looks as though the boxplot
> option *will* perform these calculations for you, if you are willing to
> move to version 4.5 or later.  The only downside of using new features
> in gnuplot is that it is noticeably harder to find help through google.

Thanks for giving me OT gnuplot support!

-- 
Karl Voit