MindSpore报错: `seed2` in `StandardNormal` should be int and >=0

1 报错描述

1.1 系统环境

Hardware Environment(Ascend/GPU/CPU): GPU
Software Environment:
– MindSpore version (source or binary): 1.6.0
– Python version (e.g., Python 3.7.5): 3.7.6
– OS platform and distribution (e.g., Linux Ubuntu 16.04): Ubuntu 4.15.0-74-generic
– GCC/Compiler version (if compiled from source):

1.2 基本信息

1.2.1 脚本

训练脚本是通过构建StandardNormal的单算子网络，生成符合正态分布的随机数。脚本如下：

 01 class Net(nn.Cell):
 02     def __init__(self, seed=2, seed2=-3):
 03         super(Net, self).__init__()
 04         self.standard_normal = ops.StandardNormal(seed=seed, seed2=seed2)
 05     def construct(self, output_shape):
 06         output = self.standard_normal(output_shape)
 07         return output
 08 
 09 output_shape = (2, 3, 4)
 10 net = Net()
 11 output = net(output_shape)
 12 print("OUTPUT: ", output)

1.2.2 报错

这里报错信息如下：

Traceback (most recent call last):
  File "C:/Users/l30026544/PycharmProjects/q2_map/new/I4DSWV-standardNormal.py", line 16, in <module>
    net = Net()
  File "C:/Users/l30026544/PycharmProjects/q2_map/new/I4DSWV-standardNormal.py", line 10, in __init__
    self.standard_normal = ops.StandardNormal(seed=seed, seed2=seed2)
  File "C:\Users\l30026544\PycharmProjects\q2_map\lib\site-packages\mindspore\ops\primitive.py", line 687, in deco
    fn(self, *args, **kwargs)
  File "C:\Users\l30026544\PycharmProjects\q2_map\lib\site-packages\mindspore\ops\operations\random_ops.py", line 67, in __init__
    Validator.check_non_negative_int(seed2, "seed2", self.name)
  File "C:\Users\l30026544\PycharmProjects\q2_map\lib\site-packages\mindspore\_checkparam.py", line 304, in check_non_negative_int
    return check_number(arg_value, 0, Rel.GE, int, arg_name, prim_name)
  File "C:\Users\l30026544\PycharmProjects\q2_map\lib\site-packages\mindspore\_checkparam.py", line 168, in check_number
    raise type_except(f'{prim_info} should be {arg_type.__name__} and must {rel_str}, '
ValueError: `seed2` in `StandardNormal` should be int and must >= 0, but got `-3` with type `int`.

原因分析

我们看报错信息，在ValueError中，写到seed2 in StandardNormal should be int and must >= 0, but got -3 with type int，意思是StandardNormal算子里的seed2属性必须是大于等于0的整数， 但是得到了一个负数。官网对两个参数seed， seed2的范围都有进行说明：

2 解决方法

基于上面已知的原因，很容易做出如下修改：

 01 class Net(nn.Cell):
 02     def __init__(self, seed=2, seed2=3):
 03         super(Net, self).__init__()
 04         self.standard_normal = ops.StandardNormal(seed=seed, seed2=seed2)
 05     def construct(self, output_shape):
 06         output = self.standard_normal(output_shape)
 07         return output
 08 
 09 output_shape = (2, 3, 4)
 10 net = Net()
 11 output = net(output_shape)
 12 print("OUTPUT: ", output)

此时执行成功，输出如下：

OUTPUT: [[[-0.7503836 -1.4105444 1.689283 1.0585287 ]
[ 0.19296396 -1.1577806 -0.9638309 -0.01727804]
[ 0.3017666 -1.1502111 -0.3734214 -0.4361166 ]]

[[ 0.7154948 0.6556154 2.3681476 1.1285974 ]
[-0.42168498 -0.2680572 -0.9242947 1.0003353 ]
[-0.4574307 0.36757398 -0.28976655 0.4996464 ]]]

3 总结

定位报错问题的步骤：

1、找到报错的用户代码行：self.standard_normal = ops.StandardNormal(seed=seed, seed2=seed2);

2、 根据日志报错信息中的关键字，缩小分析问题的范围t seed2 in StandardNormal should be int and must >= 0, but got ;

3、需要重点关注变量定义、初始化的正确性。

4 参考文档

4.1 StandardNormal算子API接口