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How to avoid the drawing of non consecutive time series values using cumulative y values in a with lines plot

For this data:

02/29/2020|2
03/01/2020|1
03/06/2020|1
03/07/2020|1
03/11/2020|5
03/12/2020|3

how can you graph something like this:

sample graph

As you can see, my x time data jumps from March 7 to March 11, so a simple with lines will connect point March 7 to point March 11, I don't want that behaviour. Finally, how can you plot so that the x and y pairs are like this

02/29/2020|2
03/01/2020|3
03/06/2020|4
03/07/2020|5
03/11/2020|10
03/12/2020|13

where y keeps adding its previous values:

Solution

  • Can you add empty lines into your data? Then you could do it like this:

    Code:

    ### plot cumulated data over time
reset session

myTimeFmt = "%m/%d/%Y"
set datafile separator "|"

$Data <<EOD
02/29/2020|2
03/01/2020|1

03/06/2020|1
03/07/2020|1

03/11/2020|5
03/12/2020|3
EOD

set format x "%m/%d" time
set style line 1 pt 7 lc rgb "red"
set yrange [0:]
set key top left

mySum = 0
plot $Data u (timecolumn(1,myTimeFmt)):(mySum=mySum+$2) w lp ls 1 title "cumulative"
### end of code

    Result:

    enter image description here

    Addition:

    If you need to insert emtpy lines between non-consecutive days, you can do this also with gnuplot.

    ### plot cumulated data over time (+ insert emtpy line after non-consecutive days)
reset session

myTimeFmt = "%m/%d/%Y"
set datafile separator "|"

Data = "$Data"          # if your data is in a file
# Data = "'Data.dat'"   # uncomment this line and enter your filename
                        # and skip the following datablock
$Data <<EOD
02/29/2020|2
03/01/2020|1
03/06/2020|1
03/07/2020|1
03/11/2020|5
03/12/2020|3
EOD

# create data with whitespace as column separator
set table $Data2
    plot @Data u (strcol(1)):2 w table
unset table

# with emtpy line between two non-consecutive days
set print $Data3
    do for [i=1:|$Data2|-1] {
        if (strptime(myTimeFmt,word($Data2[i+1],1)) > \
            strptime(myTimeFmt,word($Data2[i],1))+86400) \
           {print $Data2[i]; print '' }
        else {print $Data2[i]}
    }
    print $Data2[|$Data2|]
set print
print $Data3

set datafile separator whitespace
set format x "%m/%d" time
set style line 1 pt 7 lc rgb "red"
set yrange [0:]
set key top left

mySum = 0
plot $Data3 u (timecolumn(1,myTimeFmt)):(mySum=mySum+$2) w lp ls 1 title "cumulative"
### end of code

    Result: (same as above)