提示：平心而论，此内容不属于面试题，没有可考性，但是对大家平时代码调试很有帮助，所以我就收录进来，自成一个小节。
torch.set_printoptions函数用于设置打印选项：
torch.set_printoptions(precision=None, threshold=None, edgeitems=None, linewidth=None, profile=None, sci_mode=None)
参数介绍：
- precision – Number of digits of precision for floating point output (default = 4).
- threshold – Total number of array elements which trigger summarization rather than full repr (default = 1000).
- edgeitems – Number of array items in summary at beginning and end of each dimension (default = 3).
- linewidth – The number of characters per line for the purpose of inserting line breaks (default = 80). Thresholded matrices will ignore this parameter.
- profile – Sane defaults for pretty printing. Can override with any of the above options. (any one of default, short, full)
- sci_mode – Enable (True) or disable (False) scientific notation. If None (default) is specified, the value is defined by torch._tensor_str._Formatter. This value is automatically chosen by the framework.
说明：参数设置来源于NumPy。Pytorch官方用调侃的口吻说：Items shamelessly taken from NumPy。
代码举例：
>>> # Limit the precision of elements
>>> torch.set_printoptions(precision=2)
>>> torch.tensor([1.12345])
tensor([1.12])
>>> # Limit the number of elements shown
>>> torch.set_printoptions(threshold=5)
>>> torch.arange(10)
tensor([0, 1, 2, ..., 7, 8, 9])
>>> # Restore defaults
>>> torch.set_printoptions(profile="default")
>>> torch.tensor([1.12345])
tensor([1.1235])
>>> torch.arange(10)
tensor([0, 1, 2, 3, 4, 5, 6, 7, 8, 9])
