Cannot plot straight lines in gnuplot without showing different point types

Question

I'm using gnuplot to plot a figure, but the plot keeps giving me different point types instead of a straight line. I want to plot them using only straight lines but keep getting x's or plus signs or different symbols. Here is what I have for the gnuplot script.

set terminal pdf
set output "temperatures.pdf"
set style line 1 lc rgb "red" lt 1
set style line 2 lc rgb "blue" lt 1
set style line 3 lc rgb "purple" lt 1
set style line 4 lc rgb "orange" lt 1
set style line 5 lc rgb "cyan" lt 1
set xrange [0:780]
set yrange [0:88]
set xlabel "Time (s)"
set ylabel "Temperature (°C)"
set key bottom right
plot "data.dat" using 6:1 ls 1 notitle, "data.dat" using 6:2 ls 2 notitle, "data.dat" using 6:3 ls 3 notitle, "data.dat" using 6:4 ls 4 notitle, "data.dat" using 6:5 ls 5 notitle, \
    NaN ls 1 title "600 MHz", NaN ls 2 title "800 MHz", NaN ls 3 title "1100 MHz", NaN ls 4 title "1300 MHz", NaN ls 5 title "1500 MHz"

theozh theozh · Accepted Answer · 2020-09-23T04:29:21

There are different plotting styles, e.g. with points, with lines, with linespoints and many others. You can also abbreviate the the styles via w p, w l and w lp. Check help with. If you don't specify anything, the default is with points. That's what you are getting. Setting a line style or linetype does not necessarily mean that you are plotting only a line. You also have to explicitely use with lines.

By the way, you can use the last used file by specifying ''. And for readability you can write multiple lines by separating with \ (note, \ must be the last character in the line, no space or others characters allowed afterwards).

Try the following:

plot "data.dat" u 6:1 w l ls 1 title "600 MHz", \
     '' u 6:2 w l ls 2 title "800 MHz", \
     '' u 6:3 w l ls 3 title "1100 MHz", \
     '' u 6:4 w l ls 4 title "1300 MHz", \
     '' u 6:5 w l ls 5 title "1500 MHz"

Cannot plot straight lines in gnuplot without showing different point types

1 Answers