FIT_MAXITER = 10
set angles radians
s(x) = a * sin(2*pi*f/10000000*x - p ) + o
f = $2
a = 300
o = 513
p = 1
fit  s(x) "$0" using 1:2 via p
fit  s(x) "$0" using 1:2 via p,a
fit  s(x) "$0" using 1:2 via p,a,o
FIT_MAXITER = 10
fit s(x) "$0" using 1:2 via p,a,o,f
#set nokey
#set terminal png
#set output "$1"
set xlabel "Samples at 10MHz"
set xlabel
set ytics auto
set ylabel "ADC"
set multiplot
set format y "%5.0f"
set size 1, 0.7
set origin 0, 0.3
plot "$0" using 1:2 with lines, s(x) title "s(x) = a * sin(2*pi*f/10000000*x - p ) + o"
# 2kHz, 2000.04 Hz found
set origin 0, 0.0
set size 1, 0.3
set xlabel "Samples at 10MHz"
set ylabel "RES"
set ytics 2
plot "$0" using 1:(column(2)-s(column(1) ) ) with lines title ""
set nomultiplot
set output
set size 1, 1
set origin 0, 0
pause -1