If we want to plot function f(x) in range of [a:b] and [c:d] (i.e., a broken axes graph), we can define a new function:

g(x) = f(x) a<= x <= b g(x) = f(x+c-b-dx) b+dx <= x <= b+dx-c+d g(x) = 1/0 other xwhere dx is the gap length. We plot this new function and modify xtics to a right one. Then we get a broken x-axes graph which will similar to the one we plotted last time. Let us start work our idea out.

reset set term png set output "broken_axes2.png" #Plot f(x)=sin(x**2/4.) at range [20:22] and [40:42] f(x)=sin(x**2/4.) g(x)=20<x && x<22 ?f(x) :22<x && x<22.2 ?1/0 :22.2<x && x<24.2 ?f(x+17.8) :1/0 set xrange [20:24.2] set yrange [-1:1] set sample 2000 set border 2+8 #the bottom and top border will be plotted mannually set arrow 1 from 20,-1 to 22,-1 nohead #bottom and top border set arrow 2 from 22.2,-1 to 24.2,-1 nohead set arrow 3 from 20,1 to 22,1 nohead set arrow 4 from 22.2,1 to 24.2,1 nohead set arrow 5 from 21.95,-1.05 to 22.05,-0.95 nohead #axes broken indication line set arrow 6 from 22.15,-1.05 to 22.25,-0.95 nohead set arrow 7 from 21.95,0.95 to 22.05,1.05 nohead set arrow 8 from 22.15,0.95 to 22.25,1.05 nohead #Modify xtics to a right value set xtics ("20" 20,"20.5" 20.5,"21" 21,"21.5" 21.5,"22" 22,\ "40" 22.2,"40.5" 22.7,"41" 23.2,"41.5" 23.7,"42"24.2) set xlabel "Time:t(s)" set ylabel "Signal:U(V)" plot g(x) w l lw 2 notitle

Broken axes graph plotted by gnuplot |

Next time I will put this method to the datafile case.

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