Shape

Product Support Status

Product	Support Status
Atlas A3 products	√
Atlas A2 products	√

Module Import

from ge.graph import Shape

Functionality Description

Shape class inherits from Python built-in list, used to represent tensor shape dimension information. Besides having all operation capabilities of standard lists, it also provides convenient methods for calculating total element count of shape and judging if it is unknown shape. When dims is None, represents scalar (empty list).

Shape module also defines the following constants:

Constant Name	Value	Description
UNKNOWN_DIM	-1	Represents unknown dimension
UNKNOWN_DIM_NUM	-2	Represents unknown dimension count
UNKNOWN_DIM_SIZE	-1	Return value of get_shape_size() when shape is unknown

Class Definition

class Shape(list):
    def __init__(self, dims: Optional[List[int]] = None) -> None

Function List

Function	Functionality Description
__init__(dims=None)	Constructor, creates Shape object. dims is integer list, None represents scalar (empty list)
get_shape_size()	Calculates product of all dimensions in shape, i.e., total element count of tensor
is_unknown_shape()	Judges if shape contains unknown dimensions

Parameter Description

__init__ Parameter

Parameter	Type	Required	Description
dims	List[int]	No	Dimension value list, e.g., [1, 3, 224, 224]. None represents scalar (empty list). Default value is None

Return Value Description

Function	Return Type	Description
get_shape_size()	int	Product of all dimensions. Returns 0 when shape is empty (scalar); returns -1 when shape contains unknown dimension (UNKNOWN_DIM or UNKNOWN_DIM_NUM)
is_unknown_shape()	bool	Returns True if shape contains UNKNOWN_DIM (-1) or UNKNOWN_DIM_NUM (-2); otherwise returns False

Constraint Description

• dims parameter must be integer list (list of int) or None, otherwise throws TypeError.
• Shape inherits from list, therefore supports all standard list operations (indexing, slicing, iteration, len etc.).
• When shape contains unknown dimension, get_shape_size() returns -1, rather than throwing exception.

Usage Example

from ge.graph import Shape

# Create Shape object
shape = Shape([1, 3, 224, 224])

# Get total element count
print(shape.get_shape_size())  # 150528

# Judge if it is unknown shape
print(shape.is_unknown_shape())  # False

# Create Shape containing unknown dimension
unknown_shape = Shape([-1, 3, 224, 224])
print(unknown_shape.is_unknown_shape())  # True
print(unknown_shape.get_shape_size())    # -1

# Scalar shape (empty list)
scalar = Shape()
print(len(scalar))              # 0
print(scalar.get_shape_size())  # 0

# Supports list operations
print(shape[0])      # 1
print(len(shape))    # 4
print(list(shape))   # [1, 3, 224, 224]