Re: [Gnuplot-info] How to plot as function of weekday?

[theozh <th...@gm...>]

Thank you for your comments.

@John
> Does this help?
> https://stackoverflow.com/questions/17791828/gnuplot-date-time-in-x-axis
No, not helpful in my case.

@Alan
well, in my 5.2 manual there is %U and %w but no %u. I'm not sure if it can be used for what I want to achieve.


My current solution looks like the following (see example below).
If it can be done simpler, I would be happy to learn about it.
Disadvantage: I have to set xtics manually and don't see how to set mxtics.


### plot as a function of weekday
reset

$BirthData <<EOD
# "%a" "%d.%m.%Y" "%H:%M:%S" "SomeValue" "time in s from 1.1.1970"
Mon 13.02.1922 12:34:34 85.3 -1511004326.0
Tue 15.5.1962 04:12:18 73.1 -240868062.0
Wed 11.08.1948 09:12:56 97.3 -675010024.0 
Thu 01.01.1970 00:00:00 32.7 0.0
Fri 31.12.1999 09:09:09 5.3 946631349.0
Sat 13.10.2018 18:45:01 45.2 1539456301.0
Sun 15.5.1966 04:12:18 17.4 -114637662.0
EOD

set multiplot layout 2,1
set xdata time
set format x "%Y"
plot $BirthData u (timecolumn(2,"%d.%m.%Y")):4 lt 6 lc rgb "blue"

# define formula
Weekdaytime(t) = (floor(t/86400. + 3.)%7 + 7)%7 + t/86400. - floor(t/86400.)
# 86400 seconds per day
# 0=Mon, 1=Tue, 2=Wed, 3=Thu, 4=Fri, 5=Sat, 6=Sun
# (... %7+7)%7 to account for negative time before 1.1.1970
# add 3 days because time=0 is 1.1.1970 and was a Thursday
 
set xdata
set format "%g"
set xrange[0:7]
set xtics ("Mon" 0, "Tue" 1, "Wed" 2, "Thu" 3, "Fri" 4, "Sat" 5, "Sun" 6)
plot $BirthData u (Weekdaytime(timecolumn(2,"%d.%m.%Y %H:%M:%S"))):4 lt 6 lc rgb "red" not

unset multiplot
### end of code