When I tried to implement a operation in c++,Som problem came here. I tried to use sin function in forward.But there seems to be som problem that it returns false value.Code like below.

```
float angle=bottome_data[5];//this one is 0.0 in test.py
float sin_a=sin(angle);
float cos_a=cos(angle);
```

When I changed it to code below.

```
float sin_a=sin(0.0);
float cos_a=cos(0.0);
```

It works well.

I don’t find any solution.

So,could anybody give me some advise?

Thanks very much.

And the enviorments is :

```
cuda 7.5
cudnn 7.0
mxnet 1.0.0
---------------------
System:ubuntu 14.04
GPU:NVIDIA Tian X
```