shige 02/23 2010
Recently, a new book for gnuplot-4.2 was published last year,
written by M.Yamamoto in Japanese. In it, he pointed out some
problems about differences between the gnuplot binary and its
1) Gnuplot help says as the following (section "binary matrix"):
which are converted into triplets:
<x0> <y0> <z0,0>
<x0> <y1> <z0,1>
<x0> <y2> <z0,2>
: : :
<x0> <yN> <z0,N>
<x1> <y0> <z1,0>
<x1> <y1> <z1,1>
: : :
However, gnuplot seems to treat it as the following:
<y0> <x0> <z0,0>
<y0> <x1> <z0,1>
<y0> <x2> <z0,2>
: : :
<y0> <xN> <z0,N>
<y1> <x0> <z1,0>
<y1> <x1> <z1,1>
: : :
I checked it by
splot "binary.dat" binary matrix every :::0::1 w l
for an asymmetric binary data "binary.dat".
2) Help for png/jpeg/png terminal says:
set terminal gif medium size 640,480 \
xffffff x000000 x404040 \
xff0000 xffa500 x66cdaa xcdb5cd \
xadd8e6 x0000ff xdda0dd x9500d3 # defaults
However these colors are not the defaults of the terminals.
I think the comment "#defaults" should be removed.
3) Gnuplot help says as the following ("set datafile missing"):
set datafile missing "?"
set style data lines
The first `plot` will recognize only the first datum in the "3 ?" line. It
will use the single-datum-on-a-line convention that the line number is "x"
and the datum is "y", so the point will be plotted (in this case erroneously)
However, it, mentioned above, is the behavior when not using 'set
datafile missing "?"'. Using 'set datafile missing "?"', the line
"3 ?" will be ignored correctly.
4) Gnuplot help says as the following (section "variables"):
Valid names are the same as in most programming languages: they must begin
with a letter, but subsequent characters may be letters, digits, "$", or "_".
However, we can not use the character "$" as the part of the
Shigeharu TAKENO NIigata Institute of Technology
kashiwazaki,Niigata 945-1195 JAPAN
shige@... TEL(&FAX): +81-257-22-8161