Created by: chengduoZH

I think we should consider how to define the order of the parameters of the new Op. Here's the order of the parameters of the conv2d, and I don't think it's a good order.

def conv2d(input,
           num_filters,
           name=None,
           filter_size=[1, 1],
           act=None,
           groups=None,
           stride=[1, 1],
           padding=None,
           bias_attr=None,
           param_attr=None,
           main_program=None,
           startup_program=None)

Here is the order of the parameters I think are better.

def conv2d(
           input,
           num_filters,
           filter_size=[1, 1],
           stride=[1, 1],
           padding=None,
           groups=None,
           param_attr=None,
           bias_attr=None,
           act=None,
           name=None,
           main_program=None,
           startup_program=None):

Parameter order:

1. Input Variable.
2. Op common parameters: num_filters, filter_size, strides, paddings, groups.
3. parameter name and parameter initialization method (param_attr, bias_attr).
4. active.
5. name.
6. main_program and startup_program.

What do you think of it? @jacquesqiao @dzhwinter @reyoung @qingqing01