read\format\errskip Cavendish_2.dat (*) t,x
t=(t*10)/60		! 1 frame every 10s, --> min
x=x/1000		! mm -> m
x=-1.37+(x-1.06)	! left edge of board = 1.06m on our scale
			! zero of scale is 1.37m to the right of left edge
D0=10.31			! mirror-to-screen distance
th=atand(x/D0)		! theta

clear
defaults
label\x `t, min'
label\y `<theta>, <degree>'
set pchar -5
set yleadz 1
set font triumf.2
!scales 0 240 6 0 .85 4
!set yvmax 0.8
set nsxinc 5
set nsyinc 2

graph t,th

scalar\vary a,P,th0,tau,drift,t0
th0=-10.7
a=2
P=10
tau=15
drift=0

t0=60
fit\weight\e2 (t>t0)*(t<220) th=a*exp(-(t-t0)/tau)*cos(2*Pi/P*(t-t0))+th0+drift*(t-t0)

tt=[t0:220]
set pchar 0
set colour 7
graph\noaxes tt a*exp(-(tt-t0)/tau)*cos(2*Pi/P*(tt-t0))+th0+drift*(tt-t0)

set cursor -1
set %xloc 40
set %yloc 20
text `T='//rchar(60*P,`F5.1')//`<pm>'//rchar(60*FIT$E2[2],`F3.1')//` s'

th0=-9
a=-2
P=10
tau=15
drift=0

te=t0
t0=5
fit\weight\e2 (t>t0)*(t<te) th=a*exp(-(t-t0)/tau)*cos(2*Pi/P*(t-t0))+th0+drift*(t-t0)

tt=[t0:te]
set colour 6
graph\noaxes tt a*exp(-(tt-t0)/tau)*cos(2*Pi/P*(tt-t0))+th0+drift*(tt-t0)

set cursor -1
set %xloc 20
set %yloc 85
text `T='//rchar(60*P,`F5.1')//`<pm>'//rchar(60*FIT$E2[2],`F3.1')//` s'

th0=-8.5
a=2
t0=255
fit\weight\e2 (t>t0) th=a*exp(-(t-t0)/tau)*cos(2*Pi/P*(t-t0))+th0+drift*(t-t0)

tt=[t0:t[#]]
set colour 6
graph\noaxes tt a*exp(-(tt-t0)/tau)*cos(2*Pi/P*(tt-t0))+th0+drift*(tt-t0)

set cursor -1
set %xloc 70
set %yloc 85
text `T='//rchar(60*P,`F5.1')//`<pm>'//rchar(60*FIT$E2[2],`F3.1')//` s'