例如: X1=0:10 345678910 X2=0:3:11 2 0369 X3=11.5:-3:0 11.50008.50005.50002.5000例如： x1=0:10 x1 = 0 1 2 3 4 5 6 7 8 9 10 x2=0:3:11 x2 = 0 3 6 9 x3=11.5:-3:0 x3 = 11.5000 8.5000 5.5000 2.5000