My graph originally look like this:
But with error bars i get something like this:
This clearly isn't the same graph while in my description I just simply added "with errorbars".
My code is following :
plot "m20gnu.txt" using 1:2 title"Massa 20 g" pt 1 ps 0.8 lt 9,f(x) title "Best passende rechte bij massa 20 g"
and with errorbars:
plot "m20gnu.txt" using 1:2 title"Massa 20 g" with errorbars pt 1 ps 0.8 lt 9,f(x) title "Best passende rechte bij massa 20 g"
The data file looks like this:
0.16975 0.058823529 0.005 1
0.165 0.061728395 0.005 1
0.1415 0.047169811 0.005 1
0.13825 0.048543689 0.005 1
0.13975 0.045454545 0.005 1
0.1265 0.054945055 0.005 1
0.146791667 0.052083333 0.005 1
Does someone know what goes wrong here ? Thanks a lot already
When plotting without errorbars, you have using 1:2, which means: use the first column as x, and the second column as y value.
Now, plotting with errorbars requires three values. So by using the same using statement again, you are missing one value. Depending on the selected plotting style, gnuplot tries to guess the third value, if you don't specify all. The documentation for yerrorbars says:
2 columns: [implicit x] y ydelta
3 columns: x y ydelta
4 columns: x y ylow yhigh
In your case
plot "m20gnu.txt" using 1:2:3 with errorbars
should work.