GNUPLOT incorrect date behavior

Question

GNU plot is giving a strange behavior with this data, but I cannot figure our why.

here is my data example :

-2.696764488716512156e-02 2023-05-25
-2.514640039066843094e-02 2023-05-25
-2.539875589417509363e-02 2023-05-25
-2.443511139767776813e-02 2023-05-25
-2.258826690118204833e-02 2023-05-25
-2.176542240468394215e-02 2023-05-25

Now using HOURS time work, but I am trying to plot for DAYS with this configuration :

set terminal png size 1074,806
set output 'output.png'
set datafile sep ' '
set xdata time
set timefmt "%Y-%m-d%"
set format x "%m/%d"
set autoscale y
set style data lines
set xlabel 'Days'
plot "gnudataok.dat"  using 2:1 with lines lt rgb "blue"  

But I cannot get correct dates on the X axis

enter image description here

Answer 1

There is a typo in your script "%Y-%m-d%" instead of "%Y-%m-%d"

Note, if your time precision is just whole days, all these datapoints will be plotted on top of each other.

The following script (with some dates changed) will give the result below...

Script:

### time data
reset session

$Data <<EOD
-2.696764488716512156e-02 2023-05-25
-2.514640039066843094e-02 2023-05-25
-2.539875589417509363e-02 2023-05-26
-2.443511139767776813e-02 2023-05-26
-2.258826690118204833e-02 2023-05-27
-2.176542240468394215e-02 2023-05-27
EOD

myTimeFmt = "%Y-%m-%d"
set format x "%m/%d" timedate
set xlabel 'Days'

plot $Data u (timecolumn(2,myTimeFmt)):1 w lines lc rgb "blue"
### end of script

Result: