#!/usr/bin/env gnuplot
f(x)=a*x+b
g(x)=c*x+d
fit f(x) 'ps2-3-index.dat' via a,b
fit g(x) 'ps2-3-seq.dat' via c,d

set size 0.7,0.7
set terminal postscript colour eps enhanced# "NimbusSanL-Regu" fontfile "uhvr8a.pfb"

set output 'ps2-3.ps'
set ylabel "Query runtime (seconds)"
set xlabel "n"
set border
set key right top
set yrange [0:1.5]
set xrange [0:1000000]
#set xrange [1:1000]
#set logscale x
set pointsize 1.3
#set parametric
#set mxtics 5
#set mytics 0
#set grid xtics ytics mxtics mytics

plot 'ps2-3-index.dat' title "Index scan", \
     f(x) title "Index scan regression", \
     'ps2-3-seq.dat' title "Sequential scan",\
     g(x) title "Sequential scan regression"