问题
I've this data :
2020-04;26.94
2020-05;26.92
2020-06;26.89
2020-07;27.01
2020-08;26.73
2020-09;26.72
I use this gnuplot script ( I'm bound to use the 4.6 version of Gnuplot ) :
reset
FILE = "LINEARFIT.txt"
set datafile separator ";"
set xdata time
set timefmt "%Y-%d"
set format x "%Y\n%d"
plot FILE u (StartDate=timecolumn(1)):0 index 0 every ::0:0:0
EndDate = strptime("%Y-%d","2020-20")
f(x) = a*(x-StartDate) + b
FIT_LIMIT = 1e-8
fit f(x) FILE u (timecolumn(1)):2 via a,b
set terminal png truecolor size 900,520 background rgb "#eff1f0"
set output "/xxx/xxx/xxx/xxx.png"
set xrange[StartDate:EndDate]
set grid xtics, ytics
set yrange[0:30]
set format y "%g"
myLabel(n) = sprintf("%g",n)
plot FILE u (timecolumn(1)):2 w lp pt 7 lc rgb "red" notitle, \
'' using 1:2:(myLabel($2)) w labels offset 0,-0.5 notitle, \
f(x) ti "linear fit with extrapolation"
And the output is :
Can you tell me why, on the x axe, the values are displayed "Two by two" : 2020-04,2020-06,2020-08,2020-10,2020-12,2020-014,2020-16,2020-18,2020-20... While I want 2020-04,2020-05,2020-07,2020-08,2020-09,2020-10,2020-11,2020-12 ....
Could you help me ?
Thanks !
回答1:
X axes on Gnuplot 4.6
Your files are OK with "all dates" : The RHEL 7, CentOS 7 gnuplot-4.6.2, when the x axis is edited to "2020-15" (which is the maximum setting for not showing only "every second date setting")
EndDate = strptime("%Y-%d","2020-15")
The result / the gnuplot behaviour is exactly the same with e.g. gnuplot-5.2.2 .
Other example, gnuplot x labels "time %m.%y settings" https://www.linuxquestions.org/questions/linux-software-2/%5Bgnuplot%5D-ugly-labels-4175670549/#post6096000
来源：https://stackoverflow.com/questions/61340972/x-axe-on-gnuplot-4-6