Plotting filled region between two dates in Gnuplot - gnuplot

Question

On the x-axis, I have time as a date %Y-%m-%d. On the y axis I have integers.
Basically, I have a date range for each data point, usually given by a target date and a two week window on either side. I the plot the data point relative to that target window using vertical lines for the low and high ends of the window.
I would like to shade the region between the low and high end.
I tried adding " with filledcurves x1='2000-01-01'"
Thanks

Answer 1

I think you have a few options here. If there are only a few shaded regions that you want to draw, you can use a rectangle (I imagine that this will work -- though I haven't tested it):
set xdata time
set timefmt '%Y-%m-%d'
set object rectangle from first '2000-01-01',graph 0 to first '2001-01-14',graph 1 fc rgb "red" solid back
Another option is that you format your datafile like this:
#date value low-date high-date
2000-01-12 12 2000-01-01 2000-01-26
2000-02-12 12 2000-02-01 2000-02-26
2000-03-12 12 2000-03-01 2000-03-26
Note that there are two blank spaces between each "record" (triple spaced). If your file isn't triple spaced, you can do this easily (in gnuplot) using sed:
plot "< sed 'G;G' datafile.dat" ...
In the special case where low-date and high-date are exactly 3600*24*14 (number of seconds in two weeks) lower/higher than date, you can skip the last two columns and plot it like this:
NPOINTS=3 #Number of points in datafile.
YHIGH=15
set xdata time
set timefmt '%Y-%m-%d'
set style fill solid .5 noborder #somewhat transparent -- see "help fillstyle"
set yrange [0:YHIGH]
plot for [I=0:NPOINTS-1] 'test.dat' i I u 1:(YHIGH):(3600*24*14*2) w boxes,\
for [I=0:NPOINTS-1] 'test.dat' i I u 1:2 w points ls I+1
The first pass draws the rectangles, the second pass draws the points. This only works if the point is in the center of the range, and each range is exactly 3600*24*14 seconds (2 weeks). Note that you'll have to set the number of points and the YHIGH to some value which works for your data.
If the ranges can be skewed -- e.g. the range isn't centered on the point in question, you can probably do something like this:
NPOINTS=3
YHIGH=15
TIMEFMT='%Y-%m-%d'
set xdata time
set timefmt TIMEFMT
set style fill solid .5 noborder #somewhat transparent -- see "help fillstyle"
set yrange [0:YHIGH]
#difference between two times in seconds
boxwidth(s1,s2)=strptime(TIMEFMT,s1)-strptime(TIMEFMT,s2)
#average of two times -- number of seconds since 2000 epoch.
boxmidpoint(s1,s2)=(strptime(TIMEFMT,s1)+strptime(TIMEFMT,s2))/2
set macro #just to make it a little easier to read.
BOXARGS='stringcolumn(4),stringcolumn(3)'
plot for [I=0:NPOINTS-1] 'test.dat' i I u (boxmidpoint(#BOXARGS)):(YHIGH):(boxwidth(#BOXARGS)) w boxes,\
for [I=0:NPOINTS-1] 'test.dat' i I u 1:2 ls I+1