Re: datafile misparsing if non-numeric y

[Ethan A M. <sf...@us...>]

On Wednesday, 19 March, 2014 15:03:34 Jonathan Thornburg wrote:
> Consider the following datafile:
> 
> 1.5     0.3
> 2.5     undef
> 3.5     0.6
> 
> With gnuplot 4.6.3 (full "show version long" output below) I get the
> following results:
> 
> gnuplot> plot '/tmp/try-alpha.dat'
> 
> This plots three points: (1.5,0.3), (1.0,2.5), and (3.5,0.6).

Indeed.
Please see the documentation under "help missing".
It's on page 105 of this version of the manual
	http://gnuplot.sourceforge.net/docs_4.7/gnuplot.pdf
with sample scripts and output.

I have always considered that behaviour broken even though it
was apparently intentional.  It has been revised for version 5.
The new treatment is already present in the development
version.

	Ethan


> It seems to me that the second of these is wrong: it has an x coordinate
> which does not occur anywhere in the data file, and a bogus y coordinate
> too.  I get the same behavior if I change the "undef" to "foo".
> 
> For what it's worth,
> 
> gnuplot> plot '/tmp/try-alpha.dat' using 1:2
> 
> simply ignores the point-with-non-numeric-y as expected.
> 
> 
> 
> Here's the output of 'show version long' for my gnuplot:
> 
> gnuplot> show version long
> 
>         G N U P L O T
>         Version 4.6 patchlevel 3    last modified 2013-04-12 
>         Build System: OpenBSD amd64
> 
>         Copyright (C) 1986-1993, 1998, 2004, 2007-2013
>         Thomas Williams, Colin Kelley and many others
> 
>         gnuplot home:     http://www.gnuplot.info
>         faq, bugs, etc:   type "help FAQ"
>         immediate help:   type "help"  (plot window: hit 'h')
> Compile options:
> -READLINE  +LIBREADLINE  -HISTORY  
> -BACKWARDS_COMPATIBILITY  +BINARY_DATA  
> +GD_PNG  +GD_JPEG  +GD_TTF  +GD_GIF  +ANIMATION  
> -USE_CWDRC  +X11  +X11_POLYGON  +MULTIBYTE  +X11_EXTERNAL +USE_MOUSE  +HIDDEN3D_QUADTREE  
> +DATASTRINGS  +HISTOGRAMS  +OBJECTS  +STRINGVARS  +MACROS  +IMAGE  +USER_LINETYPES +STATS 
> 
> GNUPLOT_DRIVER_DIR = "/usr/local/libexec/gnuplot/4.6"
> GNUPLOT_PS_DIR     = "/usr/local/share/gnuplot/4.6/PostScript"
> HELPFILE           = "/usr/local/share/gnuplot/4.6/gnuplot.gih"
> 
> gnuplot> 
> 
> ciao,
> 
>