melted_sample.csv

name,x1,x2,t,y
a,1,0,1.0,1.0
a,1,0,3.0,3.0
a,1,0,5.0,5.0
a,1,0,7.0,7.0
a,1,0,9.0,9.0
b,2,0,2.0,4.0
b,2,0,4.0,8.0
b,2,0,5.0,10.0
b,2,0,7.0,14.0
b,2,0,10.0,20.0
c,3,0,1.0,0.1
c,3,0,2.0,0.2
c,3,0,4.0,0.4
c,3,0,6.0,0.6
c,3,0,8.0,0.8
c,3,0,10.0,1.0
d,4,0,2.0,1.0
d,4,0,3.0,1.5
d,4,0,4.0,2.0
d,4,0,5.0,2.5
d,4,0,8.0,4.0
d,4,0,10.0,5.0
e,5,0,1.0,3.0
e,5,0,3.0,9.0
e,5,0,4.0,12.0
e,5,0,6.0,18.0
e,5,0,10.0,30.0