Yes, its slower. Please use round()

```
[rmaheshw@rmaheshw-ld tmp]$ cat round.py
import sys
import numpy

a = sys.argv[1]
if a == "n":
  for i in range(0,100000):
    j = i*1.9999
    k = numpy.round_(j,2)
else:
  for i in range(0,100000):
    j = i*1.9999
    k = round(j,2)

[rmaheshw@rmaheshw-ld tmp]$ time python round.py n

real    0m1.800s
user    0m1.783s
sys     0m0.016s
[rmaheshw@rmaheshw-ld tmp]$ time python round.py a

real    0m0.147s
user    0m0.127s
sys     0m0.020s
```