How do I chart categorical, cumulative, and time-dependent data?

I have a bunch of time-dependent data, non-decreasing and right-continuous, always with come category involved, that can be repeated. I am looking for a sort of a variable width-bar chart, or cascade chart, flipped on it's side, from the right. For example,

set term postscript eps enhanced
set output "so.eps"
$Data <<EOD
# date	source	reg	sic	pic	total
2000-07-25	2000glider	C-FJSN	8	0	216
2000-07-28	2000glider	C-FJSN	10	0	226
2000-07-28	2000glider	C-FJSN	11	0	237
2000-07-28	2000glider	C-GCLB	4	0	241
2000-07-29	2000glider	C-GCLY	3	0	244
2000-07-29	2000glider	C-GCLY	2	0	246
2000-07-29	2000glider	C-GCLY	17	0	263
2000-07-30	2000glider	C-GCLB	15	0	278
2000-07-30	2000glider	C-GCLB	0	13	291
2000-07-30	2000glider	C-GCLK	11	0	302
2000-07-30	2000glider	C-FJSN	0	16	318
2000-07-30	2000glider	C-GCLB	0	10	328
2000-08-02	2000glider	C-GQRT	0	13	341
2000-08-04	2000glider	C-GCLY	0	11	352
2000-08-05	2000glider	C-GCLB	12	0	364
2000-08-05	2000glider	C-GCLB	0	12	376
2000-08-06	2000glider	C-GCLB	0	11	387
2000-08-07	2000glider	C-GFMB	0	12	399
2000-08-07	2000glider	C-GCMB	0	11	410
2000-08-08	2000glider	C-GCLK	0	12	422
2000-08-09	2000glider	C-GCLB	14	0	436
2000-08-09	2000glider	C-GCLB	0	9	445
2000-08-10	2000glider	C-GCLL	0	10	455
EOD
set monochrome
set xdata time
set timefmt "%Y-%m-%d"
set xtics format "%Y-%m-%d" rotate by -30
set ylabel "hours"
set grid
unset key
unset border
plot $Data using 1:($6/60) with fillsteps lw 2, \
$Data using 1:($6/60):3 with labels

Which gives,

I'm trying to create like a cumulative distribution function, where hours, in this case, are added. I want the line to go to zero on the left and the maximum value on the right. The labels, instead of printing, should be in the key and mapped to the data, grouped with other consecutive data, from the right. Is there such a plot, and how to I create it?

I have full control over the input, so I was thinking maybe an inverse-transform and rotate would be easier?

Not sure if I fully understood all your points correctly.
Maybe the following script might bring you closer to what you want.

Update:

If you want color bars for intervals then you could use the plotting style with boxxyerror (check help boxxy).

• with boxxy requires either 4 or 6 columns. 4 columns would be (x):(y):(dx):(dy) for a box centered at x,y with +/-dx and +/-dy.

• sum up your durations which are either in column 4 or 5 in the variable total. No need for column 6.

• the difference dx=43200 (i.e. half a day in seconds)

There are different ways of plottings steps.

Script:

### cumulative plot with color code
reset session
$Data <<EOD
# date  source  reg sic pic total
2000-07-25  2000glider  C-FJSN  8   0   216
2000-07-28  2000glider  C-FJSN  10  0   226
2000-07-28  2000glider  C-FJSN  11  0   237
2000-07-28  2000glider  C-GCLB  4   0   241
2000-07-29  2000glider  C-GCLY  3   0   244
2000-07-29  2000glider  C-GCLY  2   0   246
2000-07-29  2000glider  C-GCLY  17  0   263
2000-07-30  2000glider  C-GCLB  15  0   278
2000-07-30  2000glider  C-GCLB  0   13  291
2000-07-30  2000glider  C-GCLK  11  0   302
2000-07-30  2000glider  C-FJSN  0   16  318
2000-07-30  2000glider  C-GCLB  0   10  328
2000-08-02  2000glider  C-GQRT  0   13  341
2000-08-04  2000glider  C-GCLY  0   11  352
2000-08-05  2000glider  C-GCLB  12  0   364
2000-08-05  2000glider  C-GCLB  0   12  376
2000-08-06  2000glider  C-GCLB  0   11  387
2000-08-07  2000glider  C-GFMB  0   12  399
2000-08-07  2000glider  C-GCMB  0   11  410
2000-08-08  2000glider  C-GCLK  0   12  422
2000-08-09  2000glider  C-GCLB  14  0   436
2000-08-09  2000glider  C-GCLB  0   9   445
2000-08-10  2000glider  C-GCLL  0   10  455
EOD
# get a unique list from datablock
addToList(list,col) = list.( strstrt(list,'"'.strcol(col).'"') > 0 ? \
'' : ' "'.strcol(col).'"')
Uniqs = ''
stats $Data u (Uniqs=addToList(Uniqs,3)) nooutput
Uniq(i)     = word(Uniqs,i)
getIndex(s) = sum [_i=1:words(Uniqs)] s eq word(Uniqs,_i) ? _i : 0
myTimeFmt = "%Y-%m-%d"
set format x myTimeFmt timedate
set xtics format myTimeFmt rotate by -30
set ylabel "hours"
set format y "%tH:%tM" timedate
set grid
set key out reverse Left noautotitle
set style fill solid 0.5
plot  total=0 $Data u (timecolumn(1,myTimeFmt)):(dy=($4+$5)*60,total=total+dy) w steps lc "black" dt 3, \
total=0 ''    u (timecolumn(1,myTimeFmt)):(dy=($4+$5)*60,total=total+dy,total-dy/2.): \
(43200):(dy/2.):(getIndex(strcol(3))) w boxxy lc var, \
for [i=1:words(Uniqs)] keyentry w boxxy lc i ti Uniq(i)
### end of script

Result: