From: korz@cs.columbia.edu (Frederick Korz)
Subject: Re: Bar graphs w/ error bars ?
Organization: Columbia University Department of Computer Science
Date: Thu, 28 Jan 1993 14:33:50 GMT

In article <1k6a6hINN9gc@controversy.math.lsa.umich.edu> Hal.Varian@umich.edu writes:
>> >>>>> On 14 Jan 1993 16:28:19 GMT, schreine@byron.u.washington.edu (Robert  
>Schreiner) said:
>> > NNTP-Posting-Host: byron.u.washington.edu
>> 
>> > Greetings,
>> 
>> > I have a number of very wonderful and useful plotting apps that do
>> > great things, but cannot find a app that allows me to make bargraphs with
>> > error bars.  Does anyone know of an app for the NeXT with this capability
>> > (preferably shareware) ?
>
>You probably want to use HippoDraw, but it is also worth pointing out the  
>Mathematica routine ErrorListPlot.  See index to Wolfram's book for  
>documentation.

Yet another possibility is GNUplot-3.2, or the about-to-be-released
3.3.  Copyrighted but freely redistributable.  (The name is a
historical accident. GNUplot is not a Free SOftware Foundation
product.)

Driven by a command line interface or optional command files, GNUplot
has all sorts of output modes including a NeXT and X-11 screen drivers
and ability to save postscript, encapsulated postscript, latex, ... to
files.  (Can you say "good for research papers"?)

It does many things, including, I think, what you ask.  Here's the
builtin help item for errorbars from a beta version of 3.3 but it is
essentially unchanged from the commonly available 3.2 version.

The only thing it lacks is a GUI (graphical user interface) although I
seem to recall someone has wedded a GUI to an old gnuplot (3.1 or
earlier).

================
gnuplot> help errorbars
 Error bars are supported for 2-d data file plots by reading one or
 two additional columns specifying ydelta or ylow and yhigh
 respectively. No support exists for x error bars or any error bars
 for `splot`s.

 In the default situation, GNUPLOT expects to see three or four
 numbers on each line of the data file, either (x, y, ydelta) or
 (x, y, ylow, yhigh). The x coordinate must be specified. The order
 of the numbers must be exactly as given above. Data files in this
 format can easily be plotted with error bars:

         plot "data.dat" with errorbars

 The error bar is a vertical line plotted from (x, ylow) to (x,
 yhigh). If ydelta is specified instead of ylow and yhigh,
 ylow=y-ydelta and yhigh=y+ydelta are derived. If there
 are only two numbers on the line, yhigh and ylow are both set to
 y. To get lines plotted between the data points, `plot` the
 data file twice, once with errorbars and once with lines.

 If y autoscaling is on, the y range will be adjusted to fit the
 error bars.

 The `using` option may be used to specify how columns of the data file
 are to be assigned to x, y, ydelta, ylow, and yhigh. The x column must
 be provided and both the x and y columns must appear before the
 errorbar columns. If three column numbers are given, they are x, y,
 and ydelta. If four columns are given, they are x, y, ylow, and
 yhigh.

 Examples:

         plot "data.dat" using 1:2:3:4 with errorbars
         plot "data.dat" using 3:2:6 with errorbars
         plot "data.dat" using 3:4:8:7 with errorbars

 The first example reads, x, y, ylow, and yhigh, from columns 1, 2, 3,
 and 4. This is equivalent to the default.  The second example reads x
 from the third column, y from second and ydelta from the sixth column.
 The third example reads x from the third column, y from the fourth,
 ylow from the eighth, and yhigh from seventh columns.

 See also `plot using` and `plot style`.
=========================

Fred Korz			450 Computer Science Building
korz@cs.columbia.edu		Columbia University
(212) 939-7068			NY, NY  10027 (USA)
Newsgroups: comp.sys.next.software