Re: [Gnuplot-info] ploting if a special character exist in the line

[Leo B. <l_b...@us...>]

   >From mailnull  Tue Sep  3 16:50:17 2013
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   Date: Tue, 3 Sep 2013 09:49:33 -0700
   From: Mahmood Naderan <nt_...@ya...>
   Reply-To: Mahmood Naderan <nt_...@ya...>
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   Thanks for the quick reply. I understood it but I receive error. Again here is the data file

    100 10 M
    150 20 M
    30 40 H
    50 90 M

   So I ran 
     plot "data.txt" u 1:($3=='M':$2:1/0)
   

It should be ($3 eq 'M' ? $2 : 1/0) except that $3 is parsed as a
number, not a string, so even then you don't get what you want.

   So I expect that it compares the third column to 'M' and on a match return the second column. Isn't that? Now I receive

     None-numeric string found where a numeric expression was expected.

I think

plot "< awk '/M$/{print $1\" \"$2}' data.txt" u 1:2

does what you want.

Leo