Re: comment handling

[sfeam (E. Merritt) <eam...@gm...>]

On Thursday, 24 May 2012, pl...@pi... wrote:
> On 05/23/12 23:24, Ethan A Merritt wrote:

> > gnuplot>  help set datafile comment
> >   The `set datafile commentschars` tells `gnuplot` what characters are used in a
> >   data file to begin comment lines. If the first non-blank character on a line is
> >   one of the specified characters then the rest of the input line is ignored.
> >   Default value of the string is "#!" on VMS and "#" otherwise.
> >

> OK, my bad, but this does point out something that could be done better.
> 
> gnuplot>  help set datafile comment
> 
> but the following
>       1 # 3 4
>   produces rather unexpected plot unless
>       set datafile missing '#'
>   is specified as well.

Er, what were you expecting?

> Unexpected indeed. Is there a good reason why this needs to happen?  I 
> suppose this falls into the category of "except in numbers" in 'help 
> comment'.
> 
> I often need to add a comment at the end of some data lines. This is OK 
> if all expected columns are filled since gnuplot does not try to parse 
> the rest.
> 
> Is there a context in which a valid data entry could begin with '#' ?

Sure - why not?  
Data files can contain anything at all, not necessarily numeric.