关于 java 中 Double 型 用于计算产生的误差举例 ，应该用BigDecimal代替Double
乘法
use Double BigDecimal
1.4×1.5= 2.0999999999999996 2.10
1.4×1.6= 2.2399999999999998 2.24
1.4×1.9= 2.6599999999999997 2.66
1.4×2.3= 3.2199999999999998 3.22
1.5×1.6= 2.4000000000000004 2.40
1.5×1.9= 2.8499999999999996 2.85
1.5×2.1= 3.1500000000000004 3.15
1.5×2.2= 3.3000000000000003 3.30
1.5×2.3= 3.4499999999999997 3.45
1.6×1.8= 2.8800000000000003 2.88
1.6×2.1= 3.3600000000000003 3.36
1.6×2.2= 3.5200000000000005 3.52
1.6×2.3= 3.6799999999999997 3.68
1.7×2.3= 3.9099999999999997 3.91
1.8×2.1= 3.7800000000000002 3.78
1.8×2.2= 3.9600000000000004 3.96
1.9×2.1= 3.9899999999999998 3.99
1.9×2.3= 4.369999999999999 4.37
2.1×2.2= 4.620000000000001 4.62
除法
4.2/1.4= 3.0000000000000004 3.0
4.8/1.6= 2.9999999999999996 3.0
5.7/1.9= 3.0000000000000004 3.0
6.6/2.2= 2.9999999999999996 3.0
6.9/2.3= 3.0000000000000004 3.0
4.2－1.4= 2.8000000000000003 2.8
4.8－1.6= 3.1999999999999997 3.2
5.1－1.7= 3.3999999999999995 3.4
5.4－1.8= 3.6000000000000005 3.6
5.7－1.9= 3.8000000000000003 3.8
6.3－2.1= 4.199999999999999 4.2
6.6－2.2= 4.3999999999999995 4.4
6.9－2.3= 4.6000000000000005 4.6
[1.4] 累加
1次: 1.4 1.4
2次: 2.8 2.8
3次: 4.199999999999999 4.2
4次: 5.6 5.6
5次: 7.0 7.0
6次: 8.4 8.4
7次: 9.8 9.8
8次: 11.200000000000001 11.2
9次: 12.600000000000001 12.6
10次: 14.000000000000002 14.0
[1.6]累加。
1次: 1.6 1.6
2次: 3.2 3.2
3次: 4.800000000000001 4.8
4次: 6.4 6.4
5次: 8.0 8.0
6次: 9.6 9.6
7次: 11.2 11.2
8次: 12.799999999999999 12.8
9次: 14.399999999999999 14.4
10次: 15.999999999999998 16.0
[1.7]累加。
1次: 1.7 1.7
2次: 3.4 3.4
3次: 5.1 5.1
4次: 6.8 6.8
5次: 8.5 8.5
6次: 10.2 10.2
7次: 11.899999999999999 11.9
8次: 13.599999999999998 13.6
9次: 15.299999999999997 15.3
10次: 16.999999999999996 17.0
[1.8]累加。
1次: 1.8 1.8
2次: 3.6 3.6
3次: 5.4 5.4
4次: 7.2 7.2
5次: 9.0 9.0
6次: 10.8 10.8
7次: 12.600000000000001 12.6
8次: 14.400000000000002 14.4
9次: 16.200000000000003 16.2
10次: 18.000000000000004 18.0
[1.9]累加。
1次: 1.9 1.9
2次: 3.8 3.8
3次: 5.699999999999999 5.7
4次: 7.6 7.6
5次: 9.5 9.5
6次: 11.4 11.4
7次: 13.3 13.3
8次: 15.200000000000001 15.2
9次: 17.1 17.1
10次: 19.0 19.0
[2.1]累加。
1次: 2.1 2.1
2次: 4.2 4.2
3次: 6.300000000000001 6.3
4次: 8.4 8.4
5次: 10.5 10.5
6次: 12.6 12.6
7次: 14.7 14.7
8次: 16.8 16.8
9次: 18.900000000000002 18.9
10次: 21.000000000000004 21.0
[2.2]累加。
1次: 2.2 2.2
2次: 4.4 4.4
3次: 6.6000000000000005 6.6
4次: 8.8 8.8
5次: 11.0 11.0
6次: 13.2 13.2
7次: 15.399999999999999 15.4
8次: 17.599999999999998 17.6
9次: 19.799999999999997 19.8
10次: 21.999999999999996 22.0
[2.3]累加。
1次: 2.3 2.3
2次: 4.6 4.6
3次: 6.8999999999999995 6.9
4次: 9.2 9.2
5次: 11.5 11.5
6次: 13.8 13.8
7次: 16.1 16.1
8次: 18.400000000000002 18.4
9次: 20.700000000000003 20.7
10次: 23.000000000000004 23.0