From help-octave-request at bevo dot che dot wisc dot edu  Fri Nov 14 08:46:44 1997
Subject: empty legend key
From: Steven N Harp <snh2 at psu dot edu>
To: help-octave at bevo dot che dot wisc dot edu
Date: Fri, 14 Nov 1997 09:46:36 -0500 (EST)

Using octave-2.0.9 and gnuplot 3.6 beta I often want to turn of the
key or legend.I am able to do so with the following command

octave:89> plot(1:10,";;")

However I also get the message

warning: empty matrix found in matrix list near line 38, column 25

when I do this

I looked in __pltopt__ and I see the following line

        else
	  if (isempty (key_title))  # needs this to avoid empty matrix warning.
            key_title = char;
	  else

I added the following to the bottom of the __pltopt__.m

  if (set_key)
    if (isempty (key_title))  # needs this to avoid empty matrix warning.
       fmt = strcat (fmt, " ", TITLE, ' "" ');
    else
       fmt = strcat (fmt, " ", TITLE, ' "', key_title, '" ');
    endif

or by diff

mips {snh} 67: diff __pltopt__.m /every/software/octave/share/octave/2.0.9/m/plot/__pltopt__.m
253,257c253
<     if (isempty (key_title))  # needs this to avoid empty matrix warning.
<        fmt = strcat (fmt, " ", TITLE, ' "" ');
<     else
<        fmt = strcat (fmt, " ", TITLE, ' "', key_title, '" ');
<     endif
---
>     fmt = strcat (fmt, " ", TITLE, ' "', key_title, '" ');



With this change the warning goes away. 

Is there an easier way to do this?

Thanks

Steve