[Gretl-users] Re: A tiny error on plots
On Sun, 1 Sep 2019, luis.salazar.ramirez wrote:
Good day por you:
Last days I'm making a graphs for a work, when I tried to graph a
bandplot with values tiny it appear wrong. I looked the code and find:
In the gnuplot code generated appear:
plot '-' using 1:($2-1.96*$3):($2+1.96*$3) notitle lc rgb "#efefef" w
filledcurve, \
0 notitle w lines lt 0, \
'-' using 1:2 title 'uAC' w lines lt 1
2000 1 0.2507141113
The value 1 after 2000 it's the central value for the band in the
generated code but my script code was:
gnuplot u$i --time-series --band=0, band$i, 1.96 --with-lines \
--output=display --band-style=fill,0xefefef
I check others graphs and always appear the 1 value, for big values
there isn't problem but for tiny values the band appear in the wrong place.
The coding gretl solution: change the value 1 for the first argument in
the --band option.
Actually this is not a bug. The key point is that the first element
after "--band=" is supposed to be a series, not a scalar value, and
according to the help text it can be given by "name or ID number".
So if you type "0" in that place gretl takes it to mean the series
with ID number 0, "const", which has a constant value of 1.
A call to gnuplot which will do what you want would be something
like the following:
<hansl>
nulldata 20
setobs 1 2000 --time-series
series y = 0 # set up the zero baseline
series se_y = normal()/10
gnuplot y --time-series --band=y,se_y,1.96 --with-lines \
--output=display
</hansl>
Allin