.dos 文件中做如下测试:
已知:
1 + 1 * sum(3*20)
2022.10.04 11:48:23.124 DolphinDB
long(61)
(3 ms)
1 + 1 * sum 3 * 20
022.10.04 11:48:38.112 DolphinDB
long(61)
(2 ms)
expr(1,+,1,*,sum,3,*,20)
2022.10.04 11:49:12.558 DolphinDB
code('< 1 + 1 * sum 3 * 20 >')
(2 ms)
v = < 1 + 1 * sum 3 * 20 >
v
2022.10.04 11:53:23.102 DolphinDB
code('< 1 + 1 * sum(3 * 20) >')
(2 ms)
v.eval()
2022.10.04 11:53:55.039 DolphinDB
long(61)
(2 ms)
可是:
expr(1,+,1,*,sum,3,*,20).eval()
2022.10.04 11:49:52.451 DolphinDB
long(80)
(2 ms)
为什么是long(80)而不是long(61)呢?