data1.txt	500	1000	2000	0.5
data2.txt	250	1000	2000	0.5
data3.txt	750	1000	2000	0.5
data4.txt	1000	1000	2000	0.5
data1.txt	500	500	2000	0.5
data1.txt	500	1500	2000	0.5
data1.txt	500	2000	2000	0.5
data1.txt	500	1000	1000	0.5
data1.txt	500	1000	3000	0.5
data1.txt	500	1000	4000	0.5
data1.txt	500	1000	2000	0.25
data1.txt	500	1000	2000	0.75
data1.txt	500	1000	2000	1