# any way to turn off error msg when I catch the errors?

trying to check whether a numerical expression is NaN or not. My expression is log(arcsin(e)). If I apply N() on the expression it goes into infinite loop. I try to catch the runtime error. Everything seems to work in the following code except the error message displayed. I do not want that message in output. Any way to turn the error message off.

```
sage: def number(expr):
....: try:
....: n = N(expr)
....: except (RuntimeError):
....: n = N(NaN)
....: return n
....:
sage: expr=log(arcsin(e))
sage: a=number(expr)
Exception RuntimeError: 'maximum recursion depth exceeded in __subclasscheck__' in <type 'exceptions.RuntimeError'> ignored
# I do not want the above error message in output
sage: a
NaN
sage: a.is_NaN()
True
```