set term qt font 'serif,20' enhanced	# vetsi pismo, enhanced (recka pismena)
set xlabel "x"
set ylabel "y"

set key top left	# legenda vlevo nahore

f(x) = a + b*x		# definujeme funkci

fit f(x) 'cv10/upf_cv10_linear.txt' using 1:2:3 via a, b

plot [0:11] f(x) t "a + bx", \
	'cv10/upf_cv10_linear.txt' with yerrorbars t "y_i ± {/Symbol s}_i"